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Douglas Willinger
Sitting Bull

USA
109 Posts

Posted - 15 Apr 2018 :  10:34:00 PM  Show Profile  Reply with Quote
1970 WS 400 Ram Air 3/4 434 Build

3" journal, 4" stroke

Am having a rebuild of my 1970 Trans Am's original WS/9799915 400 block, dated January 6, 1970. (Ram Air III code up front, with the Ram Air IV modified casting number, of which a few were built.) Factory equipped lucerne blue with deluxe blue interior, with M-21 close ratio Muncie and 3.73:1 ratio Chevrolet 12 bolt, produced in February 1970 in Lordstown, Ohio. I purchased the car in December 1979 from self identified 3rd owner who had found in Waco, Texas, and soon afterwards had the engine rebuilt with stock specs, and a 0.30 overbore in 1977. At the time I purchased it, the car had a decal "City Motors, Fairborn, Ohio".

I drove it from 1980 to November 1982 when I spun a rod bearing and subsequently took the engine and car apart.

Started a resto-modification during the mid 1980s, with the idea of stock appearance with subtle and internal improvements.

R&R the sub-frame-suspension with better bushings, and big car spindles with ILE discs, and the 12 bolt, upgraded with c clip eliminator kit and 1979-1981 rear discs, with the main parts powder-coated, and replacing all brake and fuel lines with SSB stainless replacement parts.

Being aware of vin numbers but not of date codes, I sold the #12 cylinder heads to a friend of a friend who installed them on his 1977 or 1978 TA, and purchased a set of #614 service replacement heads, as part of a plan including two main parts: (1) upgrade to Ram Air IV, and (2) provide a greater punch with a longer stroke crankshaft, most economically then provided by a 3.25 main journal factory crankshaft re-machined to fit the 3" journals fof the 400. But not with a 4.21 stroke of a 455 but rather the 4" stroke of a 428, thus providing in the range of 433-435 cubic inches, to give some extra torque while retaining a greater degree of rev ability.

Stored indoors from late 1980s until Spring 2002 as I got distracted by a 1972 455HO GTO, and subsequently stored outdoors covered in plywood and plastic until February 2017, where the powder coat failed and needs redoing, though the SSB parts appear to not have aged a day. (Am seeking a shop to restore body before taking to a friend's "Firebird Farm" for assembly).

Engine parts stored indoors continuously, with the WS block which was stored continuously indoors, and is now in machine shop where it checked out ok for an overbore to 0.40. As we now have a multitude of aftermarket internal engine parts, rebuilding with stronger parts is considerably less money than during the 1900s. The best bang for the buck appears to be a SCAT 4" stroke forged standard weight crankshaft with BBC Callies rods, the latter being only about $250 costlier than Eagle or SCAT 4340s, but with apparently better strength qualities for greater sustained higher rpm operation.

I desire keeping this car with a manual transmission, but want greater flexibility, as the original M-21 close ratio with 3.73 differential gives nice torque multiplication (2.20 first gear), but alas 4000 rpm at 80 mph in top (4th) gear.

Ideally I want to switch to a 5 or 6 speed manual transmission. The most prevalent today appears to be the Tremacs, but I am more intrigued by the Richmond, for two main reasons: (1) its far wider selection of gearing options, and (2) what I read years ago when it was known as the Doug Nash, about the greater efficiency of placing the gear multiplication more within the transmission than in the differential, with steeper transmission gearing coupled with a 2 series rear rather than a high 4 series or 4 series differential coupled with an overdrive. But as I would like to reduce expenses where I already have something which could more easily be swapped later, I plan on switching to an M-20 wide ratio for now, (and with the rear having to come part to re-do the powder-coat) with the 3.73 gears replaced with either 3.31 or 3.07s. See and compare the following comparison between these transmissions:

M-21
2.20 1.64 1.24 1.0

with 3.73
8.206 6.1172 4.6252 3.73

M-20
2.52 1.88 1.46 1.00

with 3.31
8.34 6.22 4.8326 3.31

with 3.07
7.73 5.7716 4.48 3.07

Note, that the M-20/3.07 combo gives not all that much less overall multiplication than the M-21/3.73 combo, and that the M-20/3.31 combo gives a bit more. With regards to the greater torque of the longer stroke and more modern camshafts, never-mind that Pontiacs were generally more torquey than the Chevrolet engines that led the close ratio trend, this appears to give a great bang for the buck, especially with the 3.31.

But what about the things that should and must be set now?

My basic engine recipe consists of (1) factory 1970 1970 WS 4 bolt main 400 block; (2) aftermarket rotating assembly of a SCAT 4340 forged steel 3" journal, 4" stroke crank swinging BBC Callies rods holding either forged or billet pistons with full floating pins; (3) rebuilt 1970 7040270 (1974 service replacement) Quadrajet; (4) 1971 455HO factory aluminum intake; (5) 2.5 outlet coated RARE Ram Air style exhaust manifolds; (6) 1970 614 heads (1973 service replacements) previously milled thus reducing the combustion chambers from 70-72cc to 65-67cc, with the cross-over ports filled with aluminum), with a moderate degree of porting added, perhaps to 270cfm rater than 330 cfm to minimize adversely affecting lower lift flow.

The basic idea is an externally stock appearing engine with significant internal improvements for far greater power while retaining street-road drive ability and longevity.

But what about?

- Pistons? I know they will be flat top design with added D dish somewhat reflecting the combustion chamber shape for better flame propagation to lower the compression ration from the 12 :1 or so that I would have with my already milled 614 heads, or the II+ that I would have with if they were at their factory 70-72cc sizing. But which brand id most preferable? Ross? Icon? CP/Carrillo? Diamond? Or? Benefits and drawbacks of each type, including forged and billet? My machinist dislike Icon, citing inferior sizing tolerance, while a thread I have seen shows a preference for CP and Diamond over Icon or Ross as the choice of serious racers.

- Rod length- 6.7 or 6.8? What are the benefits and drawbacks of each? I have seen a reference to the 6.8 rod in a 4" stroke Pontiac as ideal. Does it have any drawbacks with providing less space for the rings?

- Compression? I would ideally like to run straight 93 octane pump premium, or at least limit the amount of fuel spiking - E85, Race or Octane Boaster - to retain flexibility for lengthier trips. Some considerations: As my machinist recommends a square cutting of the heads, this shall reduce the now at 65-67cc chambers to say 62-64cc. Thus, I want to minimize any decking of the block for the sake of retaining more of a heat sink, and also minimize the size of the piston dish so as to retain flexibility for swapping heads without having to likewise mill any such replacement heads. For instance, setting the compression at 9.5 with 63 cc heads would mean probably high 8s with 72 cc heads. As I intend to always run this engine with iron Ram Air heads that came with 70-72cc from the factory, together with a more aggressive cam, I would like to set the compression of this engine build for 72cc heads to at least 10 to 1, and thus about 10.75 with 63cc heads.

Indeed, I note a comment

"Rick Holladay is adamant about using the 4" stroke in his engines. His 3,700 lb. '65 GTO ragtop has been 10.73 on 93 octane, 4-speed and all. " 455 or 428 ?

http://transamcountry.com/community/index.php?topic=34258.0

- Camshaft. My initial idea was a hydraulic roller for the potential for more area under the curve and the reduced rotational friction. But I am told of problems such as of use above 6000 rpm (I would like the capacity for sustained 6500-7000 capability), e.g. pump up, or worse a catastrophic lifter failure. Also, would not much of the friction reduction benefits from the roller be negated by the required greater valve spring pressure. I have had suggested to me the option of a solid roller. Asides from the added maintenance, what is the deal with its friction issues- e.g. are its friction reduction negated by the value springs? What's the issue of the distributes gear with either a hydraulic or solid roller setup? And given how flat tappet camshaft technology evolved by the mid 1980s with lobes considerably more aggressive than those of the 1960s, how much of a bang for the buck would either a hydraulic or solid roller give over the more proven technology of the hydraulic flat tappet cams from the mid 1980s and later, which open and close the valves significantly quicker then the 1960s era cams?

A quick comparison:

1969-1970 Ram Air III automatic
9779068 288/302 212/225 LSA 116.0
1969-1970 Ram Air III manual
9785744 301/313 224/236 LSA 115.5
1969-1970 Ram Air IV
9794041 308/320 231/240 LSA 113.5

Butler recommended hydraulic roller with 9.5cr
CCA-3315 / 3316 282/288 230/236 .340/.347 .510/ .521 .544/.555

Jim Lehert recommended SR
CCA-3315/3316 282/288 230/236 0.510"/0.521"@1.5 0.544/0.555@1.6 110 LSA,
CCA-3316/3317 288/294 236/242 0 .521"/0.540"@1.5 0.555/0.576@1.6

Butler recommended hydraulic flat tappet with 10.5 cr
XE284H 284/296, 240/246, .507/.510, 110 Hyd. (112 lsa optional)

Other HYDRAULIC FLAT Tappet Cams

Competition Cams
CCA-51-224-4 274/286 230/236 .488 I - .491 110 1800-6000
CCA-51-225-4 284 /296 240/ 246 .507 I - .510 110 2300-6500
CCA-51-226-4 294/306 250/256 .519 I - .524 110 2800-6500

Lunati Voodoo
10510703 268/276 227/233 .489/.504 LSA/ICL: 110/106 1600-5800
10510704LK 276/284 233/241 504/.527 LSA/ICL 110/106 2000-6000
10510705LK 284/292 241/249 .527/.548 LSA/ICL 110/106 2400-6200

I had to review these figures myself to see that somewhat surprisingly, that the more recent roller cams offer not so much more in opening tand closing he valves then I expected. Sure they do so way more so than the 1960s cams, but not so much with the 1980s+ hydraulic cams. For instance a 1960s 230@0.50 cam being well over 300advertsied duration (a spread of 70-80degrees), yet both the rollers and the later flat tappets such cams being high 270s/low280s advertised duration (a spread of 40-50 degrees). As I was already aware of this with my circa 1984 Comp Cams 280 flat tappet, I was hoping to see this spread between advertised and 0.50 duration reduced a bit further, perhaps at least down to 30 degrees.

Give that the roller cams are apparently not much more aggressive then the more recent flat tappet cams, I still see a potential benefit in a roller for reduced friction. But again, what is the consensus regarding how much any such friction reduction is negated by the increased valve spring pressure, as well as the reliability issues?
Perhaps a solid roller is better than a hydraulic roller due to it having greater simplicity.

But given the relative spreads between advertised and 0.50 duration lift, is the benefit worth the significantly greater cost of the parts?

And as well, what about the surrender of the added benefits of the long proven technology of having lifters that are variable duration? AKA Rhodes lifters?

Jim Hand apparently got good results with Rhodes lifters, allowing a larger cam allowing greater upper rpm power with the Rhoads variable lifter reducing the duration at lower rpms thus improving power there and thus providing greater power over a broader rpm range.

In now reviewing the Rhoads lifter line, I see that in addition to their "Original Rhoads Lifters" that they now offer two extra lines, "V-Pro Street" and "V-Max Race", each of which is adjustable. The V-Pro Street lifters can be adjusted to vary the bleed-down to reduce the lower rpm lift .010" to .025", and the likewise duration between 5 and 15 degrees at .050" cam lift, with full lift and duration coming on by about 3500 rpm. The V-Max Race are likewise adjustable to reduce lower rpm lift by as much as 0.40, and duration between 5 and 20 degrees @0.50, with full lift and duration coming on by about 4000rpm. Each of these newer adjustable lines of lifters offer greater flexibility than the original Rhodes lifters which are non adjustable and which reduce lower speed lift by about 0.10" to .020" and duration about 10-15 degrees, with full lift and duration arriving at about 3500rpm. Since the bleed-down is going to likely increase the engine's dynamic compression at lower rpms, this added adjustable feature could be quite useful in tailoring the duration and lift curves to work better with the higher static compression permitted by the cam's intrinsic duration profile, as well as further fine tuning with the flow of the cylinder head's porting.

Interestingly, Rhoads offers an additional sub variant of these adjustable variable duration lifters- rollers, yet alas not for Pontiac. Ideally I would like to see such developed for Pontiac engines and refined to ensure greater reliability, but alas that has not happened, at least not yet.

Thoughts?

Edited by - Douglas Willinger on 15 Apr 2018 10:45:12 PM

Steve C.
Chief PONTIAC

1835 Posts

Posted - 16 Apr 2018 :  12:42:10 AM  Show Profile  Reply with Quote
10.75 compression with iron heads in conjunction with a cam that has short seat timing can be an issue.



Common Misconception:

Many people mistakenly think that using higher seat pressures causes a reduction in the horsepower delivered to the flywheel because higher seat pressures (and also higher spring rates required for high performance) require horsepower to compress the springs. This thinking is simply incomplete! For every valve that is opening and its valve spring being compressed, another valve is closing and its valve spring is expanding. This expansion returns the energy to the valve train and the engine. This results in a net power loss of "0" hp. Many engineering texts refer to this as the "regenerative characteristic" of the valve train. Recent tests at Crane have shown no horsepower loss on a hydraulic roller equipped engine when changing the seat pressure from 135# to 165#. Power actually improved significantly at top end, probably due to better control of the relatively heavy valves in the engine.

In Summary:

Always run enough seat pressure to control the valve action as it returns to the seat. Heavier valves require more seat pressure. Strong, lightweight valves require less seat pressure. When in doubt, run slightly more seat pressure . . . not less.

Source: http://www.cranecams.com/faqview.php?s_id=33


.

Edited by - Steve C. on 16 Apr 2018 12:48:47 AM
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tjs44
Crazy Horse

USA
507 Posts

Posted - 16 Apr 2018 :  09:19:07 AM  Show Profile  Reply with Quote
There is no HP to be found in the longer than stock rods.Only advantage might be in a cheaper rod and a little less side loading.Tom
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Lee
Sitting Bull

171 Posts

Posted - 16 Apr 2018 :  09:51:21 AM  Show Profile  Visit Lee's Homepage  Reply with Quote
quote:
Originally posted by tjs44

There is no HP to be found in the longer than stock rods.Only advantage might be in a cheaper rod and a little less side loading.Tom



Building upon that, the "rule" I've picked up over the years is:

If the octane is more than sufficient for the compression ratio - then use a longer rod. But if you are pushing the limit of the octane, then use a shorter rod.

If you look at the "Engine Masters" engines over the last decade, in the contests where they had to use a certain octane but were allowed higher compression ratios, the rod lengths have tended to be short.

Also, look into RaceTec pistons.

CURRENT: '73 T/A clone, starting to get less boring!...
67 Firebird (sold) 11.27 @ 119.6 Feb. '05 issue HPP
69 Falcon wagon, 10.51 @ 130mph Feb. '10 issue PHR (sold)
72 Cutlass Convertible, first car, owned since '82, now with a 6.0 LS, mild, putting just under 400 hp/tq to the wheels.
www.LNLPD.com
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tjs44
Crazy Horse

USA
507 Posts

Posted - 16 Apr 2018 :  10:19:39 AM  Show Profile  Reply with Quote
Lee,in a street engine I really found no advantage in it also.The EMC was REALLY pushing the limits because they were required to start the pulls so low.I talked to Joe Sherman about it a couple times and he did not think it meant squat even in a race engine.Tom
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Blued and Painted
Chief PONTIAC

USA
3505 Posts

Posted - 16 Apr 2018 :  11:57:53 AM  Show Profile  Reply with Quote
Rod length effects piston dwell time at top and bottom dead center and changes piston speed at a given rpm at 90 crankshaft degrees from TDC.

Which way I can't remember.


Bull Nose Formula/ 461/ Q-Jet/
TH400/ 3.08 8.5 / R44TS.
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tjs44
Crazy Horse

USA
507 Posts

Posted - 16 Apr 2018 :  12:19:03 PM  Show Profile  Reply with Quote
Which means virtually NOTHING!Tom
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Steve C.
Chief PONTIAC

1835 Posts

Posted - 16 Apr 2018 :  12:54:52 PM  Show Profile  Reply with Quote
Stated- " - Camshaft. My initial idea was a hydraulic roller for the potential for more area under the curve and the reduced rotational friction. But I am told of problems such as of use above 6000 rpm (I would like the capacity for sustained 6500-7000 capability "


"Friction reduction and profile shaping are the roller tappet's distinct advantages over flat tappets. Rolling contact surfaces enjoy a lower coefficient of friction than sliding surfaces; which is an important factor in a factory production engine that needs to balance power, fuel economy and durability. But the overall friction reduction is not as great as expected, because the similar-style lifter bodies generate the same drag within their individual bores. From a performance engine builder's perspective, the primary advantage of a roller tappet is its ability to follow a more aggressive cam lobe without valvetrain distress. This allows much faster valve opening rates and provides more area under the lift curve. More lift can be achieved without the added duration required to "ramp up" to the desired lift, hence the area curve can be expanded without an increase in duration."

http://www.enginelabs.com/engine-tech/engine-tech-flat-tappet-lifters-still-viable-in-performance-engines/


If your intention is a combination in conjunction with hydraulic roller lifters for 6000 rpm it can be done with a Pontiac valvetrain mass involved with the proper lifters and valve spring pressure. Tom here (tjs44) has done it with no issues. Another gentleman I'd highly suggest on this specific subject would be Paul Carter. He has extensive experience in doing so. That said said these fellows are not going to be using the typical Comp 995 valve spring !

Paul Carter
Carter Cryogenics
www.cartercryo.com
520-409-7236
Koerner Racing Engines
520-294-5758

6500 to 7000 rpm...... now you better be talking about a solid roller set up ! Those rpm's very unlikely though unless your considering a bigger cam. Let me provide a dyno proven example....

400 block
4-inch stroke
6.8 rods
310 cfm aluminium d-port cylinder heads
Single-plane intake / 830 cfm 4150 Holley carb / no carb spacer
Comp solid roller cam part number 4875 / 4877 R 113.0
248 / 260 @ .050
.3850" / .3930" lobe lift w/ 1.6 rocker ratio .015" lash
113 lobe separation
1-3/4" headers

On the engine dyno the combination made peak power at 6100 rpm

Edited by - Steve C. on 16 Apr 2018 2:35:19 PM
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Steve C.
Chief PONTIAC

1835 Posts

Posted - 16 Apr 2018 :  1:21:20 PM  Show Profile  Reply with Quote
Area under the curve example with 'modern' lobes that might be used on a lower rpm application...

A popular Comp hydraulic flat tappet XE lobe rated with 230 degrees at .050" tappet lift and .3200" lobe lift. Knowing that you need to run additional duration with the use of a solid cam because of the lash, for the example here the popular Comp XE sold roller lobe 4873 with 236 at .050" and .3760" lobe lift. This solid roller lobe has an additional 15 percent area over the hyd flat tappet cam. Tested on a Spintron machine under running conditions with a 1.5 rocker ratio (and .016" lash on the solid) these two lobes will deliver the same 241 degrees duration 'at the lalve'. But the solid will have the additional area under the curve and will make a bit more power.

Edited by - Steve C. on 16 Apr 2018 1:24:02 PM
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Steve C.
Chief PONTIAC

1835 Posts

Posted - 16 Apr 2018 :  2:34:48 PM  Show Profile  Reply with Quote
State- "Rod length effects piston dwell time at top and bottom dead center and changes piston speed at a given rpm at 90 crankshaft degrees from TDC. Which way I can't remember."

Source:
http://www.empirenet.com/pkelley2/DynamicCR.html

"Another factor that influences DCR is rod length. It's length determines the piston location at intake closing, different rod lengths change the DCR. Longer rods position the piston slightly higher in the cylinder at intake closing. This decreases the DCR, possibility necessitating a different cam profile than a shorter rod would require. However, the effect is slight and might only be a major factor if the rod is substantially different than stock. Still it needs to be taken into account when calculating the DCR."
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Steve C.
Chief PONTIAC

1835 Posts

Posted - 16 Apr 2018 :  3:12:35 PM  Show Profile  Reply with Quote
509 hp 4-inch stroke combo
#16 iron heads / 240 cfm / 11.5 compression
Single-plane intake / 850 Holley
1-3/4" headers

250 degree solid roller cam...... peak power 5900/6000 rpm

http://www.hotrod.com/articles/0111hpp-dyno-testing-engine-wear-ii/

According to the original published article. The big drawback is the high 11.5:1 compression which required 108 octane fuel. Dial it back to a reasonable street 9.5:1 compression, and a slightly different cam, which will produce 25 less horsepower but retain the same torque figures and run pump gas.

Edited by - Steve C. on 16 Apr 2018 3:13:02 PM
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Corncob2061
Sitting Bull

USA
165 Posts

Posted - 16 Apr 2018 :  8:28:58 PM  Show Profile  Reply with Quote
Great project. I have a friend doing something very simular on 70 judge, heads are unported 614 and a automatic, he has xp coded block and matching intake and exhaust manifolds. He is wanting to go with a 4.25 or 4.5 stroke. The 4 inch is an interesting choice for the street, the 4.25 is the same cost and would probably out run the 4, plus it would keep the rpms down a little and a hyd roller cam would be perfect for the 6000 rpm range. Just like what Steve c suggests. But I can see the 4 inch crank if you plan to run a m20 or m21. High rpm with less torque might help the trans survive. I like the m20 and the 3.36 you listed.

None of the cams you listed would make it to the 6500 with the 4 inch crank imo. You will need a little wider lobe separation to blead off cylinder pressure. With 10.7 compression you might want to go with a big hyd 240+ at .050 in a less modern hydrualic grind with lots of seat timing with the vmax lifters.

The comp xe grinds shut the intake valve too fast on the valve seat. They struggle with valve control on Pontiacs 30 degree intake seat at high rpm. Lunati would be better, a lot gentler closing the valves.

I have a 4.25 stroke engine with 10.5 cr and cast iron heads running a crane solid lifter cam that runs outstanding. Crane rates the cam at 290/300 and 248/258 with 112 separation. It will pull to 6500 and not flinch. Peak power is 6200. If you look up the lobe specs it actually has 310/320 at .015 lash. I run it at .018. I run it on 91 octane I have never had detonation. Sometimes the old profiles have their place.

Jay

Edited by - Corncob2061 on 16 Apr 2018 9:38:06 PM
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Douglas Willinger
Sitting Bull

USA
109 Posts

Posted - 18 Jun 2018 :  4:30:51 PM  Show Profile  Reply with Quote
Great thread. Thanks to everyone!

Am leaning towards the 6.7 rather than the 6.8 rods owing to the latter's minimal benefits relative to the former's lesser octane requirement.

Looking elsewhere on this site, I see discussions about *dynamic* compression.

What would be such for this "434" build, with the Lunati Voodoo 705 flat tappet hydraulic cam with a 10.7 static compression. Would the asymmetrical lobe design with the gentler intake valve closing provide sufficient bleed-off with the minimal 5 degree reduction in duration with the minimum adjustment on the VMAX adjustable variable duration hydraulic lifters?

I like the idea of purchasing a rotating assembly from a single vendor, but have not found any such that offers Racetech pistons. Butler stands by Ross pistons.

Am I ok with *near* zero deck, say 0.005"
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Steve C.
Chief PONTIAC

1835 Posts

Posted - 18 Jun 2018 :  6:45:19 PM  Show Profile  Reply with Quote
I mentioned Paul Carter here, make note he has extensive dyno experience with Lunati Voodoo lobes. I also know he used the Voodoo 705 in a 4-inch stroke combination therefore I suggest you contact him regarding that. Koerner Racing Engines / 520-294-5758.

That said I will still contend sustained 6500-7000 capability is solid roller cam territory. Also a side note, I recently purchased a Lunati forged crank from Paul Knippen at Muscle Motors. And other parts from him in the past. He is very Pontiac savvy building and racing them and sells parts with very competitive pricing including pistons. Contact him at 630-400-4441 (cell).
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tjs44
Crazy Horse

USA
507 Posts

Posted - 18 Jun 2018 :  8:16:13 PM  Show Profile  Reply with Quote
This build is WAY more easy to build than is being done IMO.I have a 434 in my 63 tempest now for right at 22 years.Exactly like I built it except for diff cam changes.I have a fresh 434 sitting in my garage on a runin stand right now.Just broke it in over the weekend.Both have stock pontiac length rods,one has stupid expensive Carillo rods and the other has late stock cast rods rebuilt with ARP bolts.Both 9.5 CR.One has full race type 63 421 SD 980 heads the other bone stock 96s.Both do have forged pistons,one $500 Racetech the other 800 plus Ross.One now has a hyd roller the other a 068 hft.Both will have factory 421 SD dual quads.One with a pair of 750 AFBs the other with a pair 625 AFBs.When the stock ish one gets in the 62 GP im sure it is going to drive much better than the other,will be able to roast the tires as well as the other.What im getting at is you dont have to have exotic parts unless your going to race it as much as street drive it.Steve has been doing this a long time,I have been doing it since 1962.JMHO,Tom
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Steve C.
Chief PONTIAC

1835 Posts

Posted - 19 Jun 2018 :  11:55:25 AM  Show Profile  Reply with Quote
"Steve has been doing this a long time,I have been doing it since 1962.JMHO,Tom"

But I think I'm older than Tom

I've had my Trans Am since 1988. And have run about 9 different solid roller cams in various combos in it. One made peak power at 6900/7000 rpm, and yes it was limited street driven.

But seriously, Listen to him and seriously consider your intended RPM desires.




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Douglas Willinger
Sitting Bull

USA
109 Posts

Posted - 19 Jun 2018 :  12:40:22 PM  Show Profile  Reply with Quote
I am thinking that the basic parts offered by entities as Butler are sufficient, such as the SCAT regular forged cranks, SCAT, Eagle or Callies rods with the ARP 2000 bolts, and the Ross pistons. I see no need for a billet crank etc.

Am intrigued by the recommendations for Racetech, but have seen no specifics as to why they would be preferable to Ross. Am currently contemplating such with an 18-21 cc dish, with my approximately 64 cc 614 heads.
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tjs44
Crazy Horse

USA
507 Posts

Posted - 19 Jun 2018 :  12:49:56 PM  Show Profile  Reply with Quote
WHY?Because they are a lot cheaper!Steve,God willing I will be 74 in Dec!Tom
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Steve C.
Chief PONTIAC

1835 Posts

Posted - 19 Jun 2018 :  2:04:09 PM  Show Profile  Reply with Quote
Opps, you got me by two years !
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Steve C.
Chief PONTIAC

1835 Posts

Posted - 19 Jun 2018 :  2:09:04 PM  Show Profile  Reply with Quote
Good conversation regarding pistons...

http://forums.maxperformanceinc.com/forums/showthread.php?805794&p=5745040#post5745040

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Corncob2061
Sitting Bull

USA
165 Posts

Posted - 21 Jun 2018 :  09:04:06 AM  Show Profile  Reply with Quote
The voodoo 705 is a great cam, in shuts the valves more gental than the comps 284XE. The engines that seem to be more successful with the bigger comp xe grinds are running 45 degree seats on the intake valve, such as the edelbrock heads for pontiacs. For this build though I would look over at what the folks running in pure stock and the F.A.S.T. racing series. The hard running cars in stock are running high compression and very small cams for the et they are running. They are not at all modern grinds like the voodoo or XE. Both the fast and the stock class run upwards of 116 lobe separation. They hold the cams overlap down and are using extra compression to mimic the scavaging that cams such as the 705 and 284xe. They shut the intake valve very late broadening out the power band well past what we are use to seeing for the cams size. Stock can not run Rhoads lifters, but Rhoads v max work great for those, you can 0 lash them and nearly get the rpms as a solid cam, or set them loose to gain streetability.

Go to youtube and watch the cockpit cameras. I believe you can go to purestockdrags and find the link. Check out where some of the stock cars shift at. A lot of them shift at 6000 with cams that are similar .050 specs to pontiacs 068 cam. The big cammed engines such as ram air 2 and 4, max wedges, hemis, and chevy l88, ls6 and l79 are close to 7. Jim Mino ran a 1968 ra2 firbird for a long time and was one of the first to brake into the 11s.

Solid roller is a great and the best choice, I run one in my drag car engine. I believe it is 268/276 at at .050 with a 109lsa. Running 1/8 mike I ran it out in 2nd gear a couple times because I was shifting right before the traps. 7500 rpm. Solid roller can defineltely get it done, but I have always been amazed at what the fast pure stock cars do.
Jay
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Corncob2061
Sitting Bull

USA
165 Posts

Posted - 21 Jun 2018 :  09:18:33 AM  Show Profile  Reply with Quote
Here is the youtube link

http://www.psmcdr.com/15.html
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Corncob2061
Sitting Bull

USA
165 Posts

Posted - 21 Jun 2018 :  09:59:45 AM  Show Profile  Reply with Quote
My favorite one to watch is the silver Vette towards the end of the clips. You can see the shift light come on at 7000, and the car brakes traction at half track and goes sideways, he is running mid elevens. The 440 six pack super bee shifts a 6000, goes through the traps at 6200, all on a cam that probably only has around 216 intake degrees at .050, some brake into the elevens too. Fast for such a small cam. Can not really see any tachs on the faster pontiacs, but you can hear them.
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tjs44
Crazy Horse

USA
507 Posts

Posted - 21 Jun 2018 :  2:07:25 PM  Show Profile  Reply with Quote
It sounded after ready his want list is a good reliable street friendly engine with more power.I dont think a solid roller cam fits that bill,they require higher spring pressures,my choice would be a good hyd roller picked to get the driving range to fit where his final gear will be with a stick shift trans.Nothing worse in my mind to be driving around at 50 MPH around town and have to pull back a gear as the chugging and bucking sucks.I drive a couple Tremics and have over the years pulled back my cam shafts with 430-455 size engine to the 230-236 range on a 112.Started with 250s on both on a 108 20 some years ago and have made a few cam changes to get me know in that range.FWIW,Tom
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Corncob2061
Sitting Bull

USA
165 Posts

Posted - 21 Jun 2018 :  4:29:20 PM  Show Profile  Reply with Quote
I guess I should have wrote the best choice for high rpm is a solid roller not just the best choice. I agree with you Tom about this could be simpler, a hydrualic roller holding the rpms to 6ish with 9.5-10 compression and 230s at .050 duration and 112 lsa would be a monster and have great street manors. Going to near 11 compression, hydrualic flat tappet cam, moderate to pretty slow profiles, 230s at .050, widening the lobe separation out to 115 it takes more rpm to make the same power as the hydraulic roller cam. Just another way of doing things. With limited traction, exhuast manifolds and a 4 speed such as a m21 or m20, I think the hyd flat tappet combo with Rhoads might brake less parts, be nearly as fast, and still be decent to drive.

Tom your two cars sound like awesome rides!
Jay

Edited by - Corncob2061 on 21 Jun 2018 4:41:33 PM
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Corncob2061
Sitting Bull

USA
165 Posts

Posted - 21 Jun 2018 :  5:30:55 PM  Show Profile  Reply with Quote
I am hesitant to post this, but I will share a sliver of my experience. Hydrualic cams can rev good if done right. My brother and I built a turbo charger system on a 1972 plymouth satellite road runner clone 20 years ago. It had a 318 with stock valves and a cam similar to a 068 Pontiac. I was riding shot gun, he spooled up the turbo, let go of the brakes and gave the engine half throttle, the engine going to 5000. Went through all the gears now in drive, only going maybe 5 mph blazing the tires. He then floored it. The tach went too 7500, then buried it. The speedo went to 150, it then went down past that and pegged it. Went about 200 feet and still hardly moving, felt the back end start to shake and let off. There was so much tired speed the cars backend went around 1 and a half times after he let off gas. Got home and both tires went flat.

You can rev some hydrualic cams pretty high if so desired. You do not have to have something fancy. The hyd rollers, voodoos and xe are all great cams. But I can not imagine a hydrualic roller or one of the voodoo or xe cams doing that crazy of a high rpm burn out. The engine would have floated the valves and came apart.

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tjs44
Crazy Horse

USA
507 Posts

Posted - 21 Jun 2018 :  6:13:45 PM  Show Profile  Reply with Quote
My 366 RA V with a comp 236-242 hyd roller with 150 on the seats and a 2-4 tunnel ram with a pair of 625 AFBs made HP to 6700 and was still climbing when Joe Sherman shut the pull down.Im sure it would have gone 7000.Same cam with a single 4 single plane intake quit at 6500.Fact is that the choke can in fact be the intake more than the cam-lifters.FWIW,Tom
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Steve C.
Chief PONTIAC

1835 Posts

Posted - 21 Jun 2018 :  6:36:49 PM  Show Profile  Reply with Quote
We spun a small-block Chevy with hydraulic roller lifters to 7,700 rpm without valve float!

http://www.hotrod.com/articles/rpm-small-block-chevy-with-a-hydraulic-roller-cam/

Crane Cams 8,000 rpm Small-Block 347ci Ford Build and Test

http://www.mustangandfords.com/how-to/engine/1505-crane-cams-8000-rpm-small-block-347ci-ford-build-and-test/


Hyd roller lifters made to handle solid roller spring pressures and lobe profiles. Way beyond Malcolm 'Mac' McKellar and the glory days !
.

Edited by - Steve C. on 21 Jun 2018 6:49:36 PM
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Corncob2061
Sitting Bull

USA
165 Posts

Posted - 22 Jun 2018 :  09:46:52 AM  Show Profile  Reply with Quote
Is there a couple lobe profiles that would help spin this 433 ram air 4 build to 6500-7000, if he can find make it breath that well? I am not at all against hydrualic rollers.
Jay

Edited by - Corncob2061 on 22 Jun 2018 5:36:54 PM
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Steve C.
Chief PONTIAC

1835 Posts

Posted - 22 Jun 2018 :  09:58:01 AM  Show Profile  Reply with Quote
Somewhat related.....

http://forums.maxperformanceinc.com/forums/showthread.php?t=819010

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tjs44
Crazy Horse

USA
507 Posts

Posted - 22 Jun 2018 :  11:27:31 AM  Show Profile  Reply with Quote
The amount of cam and the type of intake,besides the flo required IMO will make for a crap street driver.I assume you want to make HP to that level just not"spin"it.For the life of me I dont understand the reasoning for it?Tom
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Steve C.
Chief PONTIAC

1835 Posts

Posted - 22 Jun 2018 :  12:25:18 PM  Show Profile  Reply with Quote
Related tid bit for interest. The trigger here....... sustained high RPM capability.


https://www.streetmusclemag.com/tech-stories/fuel-cooling-ignition-tech/tech-installing-cantons-engine-oil-cooler-and-why-you-need-one/

Edited by - Steve C. on 22 Jun 2018 12:28:39 PM
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Steve C.
Chief PONTIAC

1835 Posts

Posted - 22 Jun 2018 :  12:26:15 PM  Show Profile  Reply with Quote
Oil cooler

Edited by - Steve C. on 22 Jun 2018 12:27:34 PM
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Douglas Willinger
Sitting Bull

USA
109 Posts

Posted - 22 Jun 2018 :  3:53:41 PM  Show Profile  Reply with Quote
quote:
Originally posted by tjs44

The amount of cam and the type of intake,besides the flo required IMO will make for a crap street driver.I assume you want to make HP to that level just not"spin"it.For the life of me I don't understand the reasoning for it?Tom



Theoretical application, though not necessarily to the same degree:

https://jalopnik.com/this-is-what-koenigseggs-record-278-mph-nevada-speed-ru-1820157256

Or more realistically:

https://www.youtube.com/watch?v=u0JS3iEQJ00

I wonder about a 4" stroke build with an aftermarket block, with a 4.255 bore for the 455 that Pontiac should have produced, plus modern aluminum heads.


Edited by - Douglas Willinger on 22 Jun 2018 5:49:58 PM
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tjs44
Crazy Horse

USA
507 Posts

Posted - 22 Jun 2018 :  5:27:01 PM  Show Profile  Reply with Quote
Douglas,WHAT do you want?For what your talking about a aftermarket block is not necessary?A 455 block 30 over with a 421-428 crank will get you a good combo.If you want to drive it and be able to pull into any gas station you will want to keep your CR about 9.5.For a street car RPM be damned,go with the 4.21 crank,30 over and use the TQ.TQ is king on the street IMO.Also Joe Sherman told me the better the head the less cam needed to produce a target HP.Get your IV heads ported to 280ish CFM,use the 455 numbers and a good 240-250 112 cam and it will make tons of HP depending on your intake and carb choice.Me,I would put a Offy 2-4 with a pair of 750 true AFB carbs,not e carbs and it will drive like a 4 bbl with progressive linkage and blow the tires off the car anytime you want.The 455 in my 69 bird has bone stock 48 heads and a 230-236 cam and a 2-4 setup with a pair of 625s and makes around 475 HP and is all I want to handle on the street.Has a TKO 500 with 3.31s in the back and will cruise the highway at 2K RPMs.Tom
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Douglas Willinger
Sitting Bull

USA
109 Posts

Posted - 22 Jun 2018 :  5:58:30 PM  Show Profile  Reply with Quote
Only talking some theoretical ideas for something in the future.

I would build the longer stroke for an automatic, particularly with a larger car, such as a project I would like to do afterwards: a 1970-1972 Lemans 4 door pillar less hardtop with the 1970 GTO front, including the Ram Air set up, with 1972 GTO fender air extractor grafted in, and the now available ducktail spoiler. Say, a 1970 2 bolt 400 (they are all the same casting) with added 4 bolt caps and 4.25 stroke assembly in the 3" journal, with 1971 197 455HO heads, intake and RARE 2.5 outlet repro exhaust manifolds. I have a set of those heads, milled 0.065 and a chamber measured at 94.5cc. With no dish flat tops that would yield about 10.2cr. Or, swap on a set of #614s for 13+cr for E85, if only it were more available and not mislabeled actual E70. Could go more radical with the suspension, with tubular upper control arms up front with taller spindles and 12" brakes, and perhaps a HEIDT independent rear suspension, and make for an awesome touring car.

The Lunati 705 cam calls for 10+cr, not 9.5. Hence I am perplexed at suggestions to lower the to be built static cr to that degree.

http://www.lunatipower.com/Product.aspx?id=1778&gid=287

However, I can see dialing back the cr to the 10.25 to 10.5 range, with Racetech pistons with say a 22 cc dish, would be easier octane wise then 10.7 18-19cc dish. After all I plan on using the adjustable variable VMAX lifters, which are going to result in pressure when adjusted for greater streetability.

11+ is definitely too high with today's readily available fuels.

However I wonder, what if the recent talks about increased pump fuel octane to 95 or better, perhaps with E30, materialize?

Edited by - Douglas Willinger on 23 Jun 2018 01:16:29 AM
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Corncob2061
Sitting Bull

USA
165 Posts

Posted - 22 Jun 2018 :  5:59:49 PM  Show Profile  Reply with Quote
The 6500-7000 was the op desire, not mine. I am curious what it would take to do it though. There is a calculator on the Wallace racing site, I never played with it before but, inputting rpm,cid, percent eff, calculator for 433cid, 6500 rpm, 100 percent, and it said 270cfm head flow. Then it said also for minumum rpm at peak flow 127.5 eff was 5100 for 270 cfm if I worked it backward. Leaving the inputs 433, 6500, and 127.5 it said 322 cfm.

I follow the max numbers, min numbers are a little harder to understand.







Edited by - Corncob2061 on 22 Jun 2018 6:15:05 PM
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tjs44
Crazy Horse

USA
507 Posts

Posted - 22 Jun 2018 :  6:11:21 PM  Show Profile  Reply with Quote
Good luck with your project.Tom
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Steve C.
Chief PONTIAC

1835 Posts

Posted - 22 Jun 2018 :  7:21:44 PM  Show Profile  Reply with Quote
"Good luck with your project"
X2

"The 6500-7000 was the op desire, not mine. I am curious what it would take to do it though."

To this, and based on my personal experience. Before aftermarket blocks were available I wanted to do a engine with the specific goal of making 700 hp and doing so at or below 7000 rpm. And using a 4-inch stroke. However I went to Crower and had a custom 4.125 billet crank made for a 400 block.

Details here: http://www.pontiacstreetperformance.com/psp/racerSC01.html

It was limited street driven, unfortunately with 11.2 compression I had to add a bit of race gas to do so.



Edited by - Steve C. on 22 Jun 2018 8:15:33 PM
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tjs44
Crazy Horse

USA
507 Posts

Posted - 22 Jun 2018 :  7:31:20 PM  Show Profile  Reply with Quote
Steve,you like me know what it will take and it wont be a pump gas street friendly engine!Like I said,good luck with your project!Tom
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Steve C.
Chief PONTIAC

1835 Posts

Posted - 22 Jun 2018 :  8:03:27 PM  Show Profile  Reply with Quote
For interest, note Mike Davis build here:

http://www.hotrod.com/articles/hppp-0606-atlanta-pontiac-pavement-shootout/

And note the cylinder heads amount of cfm flow and the amount of cam duration in use. And to mirror Tom's comment....

Cylinder head flow comes into play where a better flowing head actually needs LESS camshaft duration than a lesser flowing head.

Edited by - Steve C. on 22 Jun 2018 8:11:27 PM
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Corncob2061
Sitting Bull

USA
165 Posts

Posted - 24 Jun 2018 :  10:22:17 AM  Show Profile  Reply with Quote
The Mike Davis build gets it done! 6500 rpm...Good job finding that Steve!

The hydrualic roller like what Tom is running is A LOT better at filling the cylinders than any hydrualic flat tappet profile with similar specs. That is one reason why he only need 9.5 compression to make big power numbers. Any more than 9.5 would likely start to cause detonation. Also the combination of 112LSA and the 240ish .050 exhuast seem to work great with good exhuast manifolds.

I am sorry, when I said the 705 is a great cam, I should have maybe expanded on that some. A 705 needs 10 to work reasonably well. Much higher than 10 though and you may be looking for some race gas. It has a lot more exhuast duration than what Tom is running giving it even more overlap with the 110 LSA. Most of the overlap is just sending the charge from the intake out the exhuast with exhaust manifolds on the 705. It needs a good set of headers and a good 3 inch exhaust. The overlap is meant for cylinder scavenging, what you will have with that 705 and manifold combo is reversion instead of scavaging. The exhuast will probably smell very gassy
I would suggest picking a smaller cam or wider LSA , or better yet both.

Jay

Edited by - Corncob2061 on 24 Jun 2018 11:19:21 AM
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Steve C.
Chief PONTIAC

1835 Posts

Posted - 24 Jun 2018 :  11:07:57 AM  Show Profile  Reply with Quote
"A 705 needs 10 to work reasonably well"

It would be interesting to know the 'real' difference. One popular calculator suggests at 550 hp going from 10:1 to 9.5:1 you would lose about 4 HP. Would you feel that in the seat of your pants driving, no.

I built a engine that had only 9.7 compression with aluminium heads. Not by design but by a mistake on my part. It made 580 hp with a 254 degree solid roller cam ground with a 108 lobe separation. I was told I did not have enough compression to use that cam ! I didn't lose sleep over it and certainly had no issues with pump gas on the street.








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Corncob2061
Sitting Bull

USA
165 Posts

Posted - 24 Jun 2018 :  11:24:46 AM  Show Profile  Reply with Quote
Your right on that Steve. I have seen many run lower with that cam, I have always wondered why lunati has such high compression recommendations of all their voodoos, but comp 284xe says a minumum of 9? 274xe does not even mention a min.
Jay
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Corncob2061
Sitting Bull

USA
165 Posts

Posted - 24 Jun 2018 :  12:10:01 PM  Show Profile  Reply with Quote
Thinking about running a cam with that much overlap with manifolds and full exhaust. That is going to trap a ton of heat in the engine, make it want to detonate a lot more.

Edited by - Corncob2061 on 24 Jun 2018 12:10:48 PM
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Douglas Willinger
Sitting Bull

USA
109 Posts

Posted - 24 Jun 2018 :  12:53:13 PM  Show Profile  Reply with Quote
What is the consensus on the cams offered by SD Performance and Nitemare?
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Steve C.
Chief PONTIAC

1835 Posts

Posted - 24 Jun 2018 :  1:39:58 PM  Show Profile  Reply with Quote
Both simply use Comp Cams lobes. For his hydraulic roller cams Dave for the most part orders Magnum High Lift lobes with a 112 lobe separation and keeps them in stock. Unless I'm missing something Nitemare Performance doesn't even list their specifications other than valve lift.


Edited by - Steve C. on 24 Jun 2018 1:41:03 PM
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Douglas Willinger
Sitting Bull

USA
109 Posts

Posted - 24 Jun 2018 :  2:25:20 PM  Show Profile  Reply with Quote
quote:
Originally posted by Steve C.

Both simply use Comp Cams lobes. For his hydraulic roller cams Dave for the most part orders Magnum High Lift lobes with a 112 lobe separation and keeps them in stock. Unless I'm missing something Nitemare Performance doesn't even list their specifications other than valve lift.





Correct about Nitemare. I did ask, but was told that he does not list the specs because he does not want people purchasing the cam for less money elsewhere.
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Douglas Willinger
Sitting Bull

USA
109 Posts

Posted - 24 Jun 2018 :  2:40:16 PM  Show Profile  Reply with Quote
quote:
Originally posted by Corncob2061

Thinking about running a cam with that much overlap with manifolds and full exhaust. That is going to trap a ton of heat in the engine, make it want to detonate a lot more.



Regarding the Lunati 705 with 110 LSA?

What about the 705 with 112, 113 or 114 LSA?
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Steve C.
Chief PONTIAC

1835 Posts

Posted - 24 Jun 2018 :  3:02:00 PM  Show Profile  Reply with Quote
The Voodoo lobes can be had with any lobe separation desired. Paul Carter has ordered them with a 112 when their catalog states 110.

Note my second post here:
http://psp.aquacomp.net/topic.asp?TOPIC_ID=13706&SearchTerms=Voodoo
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tjs44
Crazy Horse

USA
507 Posts

Posted - 24 Jun 2018 :  3:08:43 PM  Show Profile  Reply with Quote
I was using one of Dave cams before it WAS "Daves" cams.Tom
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