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 Street grind high ratio Solid roller valve springs
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Corncob2061
Crazy Horse

USA
516 Posts

Posted - 22 Jul 2019 :  11:28:02 AM  Show Profile  Reply with Quote
Contemplating the compcams 914 spring that have 165 seat. But I was looking through Butlers list of valve spring and I came across these:

https://butlerperformance.com/i-26759634-dhp-dual-valve-springs-dhp-s-084-283-16.html?ref=category:1234802#reviews

They are Howards, and the show 175 on the seat with a 1.45 o.d. I think they would work with the compcams 940 retainers rather than the 941 that the comp 914 take.

This cam combo is a 1.7 or 1.72 ford Windsor rocker on a .32 lift solid roller street profile, around .55-.56 lift. It is going in my 77 Trans Am. It is a solid roller 290/290 252/252 112 lsa. I changed from a UD280/288 to the isky because the SCR ended up higher than what I am comfortable with running the Ultradyne. Going to use the UD in a 455. The isky has similar overlap and exhuast duration but more duration on the intake. I am trying to hold the dcr down to 7:1. (The isky has a later intake closing and really slow ramps for the street). I am slowly making progress on the engine, I need to get this finished.

This engine has to have stock valve covers, it has ra mainifolds , all stock outside except for that. I am a little limited on clearance under the factory valve covers. I am trying to keep it looking factory. I do not think I have room for a stud girdle. What is the most spring pressure you can run without needing one with the bigger rocker ratio. 200 seat and 450 over the nose? I do not have the rockers yet, what do you guys think about a set of 1.8 rockers on this cam, Crower, prw and scorpion make some. Ever seen it done? The engine has longer than stock valves for running Windsor rockers.

Any thoughts? This combo is a bit unusual. If there is helpful info out there point me in the right direction. Thanks! Jay

Edited by - Corncob2061 on 22 Jul 2019 12:18:10 PM

Steve C.
Chief PONTIAC

2038 Posts

Posted - 22 Jul 2019 :  2:39:18 PM  Show Profile  Reply with Quote
Reminds me of a statement Dick Duclow, who was involved with the early Indian Adventures block, said about rocker arm studs that under certain conditions used without a stud girdle to support them moved around. Filmed under similar conditions he said they looked like "hula dancers".

Years ago in a 400 based engine we used a UltraDyne solid roller with 251 degrees intake duration, it made peak power at 6400 rpm. I used a stud girdle, but not with stock valve covers. They were aftermarket chrome covers but not much taller. Highly recommended if they will fit.

A caveat, your situation is a bit different. We had 0.640" lift and about 200 lbs seat pressure at the time. The high lift and stiff valve springs is big factor for the rocker studs to flex.
That and a don't think you intend to be at that higher rpm level.


Edited by - Steve C. on 22 Jul 2019 3:22:13 PM
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Steve C.
Chief PONTIAC

2038 Posts

Posted - 22 Jul 2019 :  4:05:43 PM  Show Profile  Reply with Quote
Jay, have you determined the actual installed height the springs will come in at ?
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Corncob2061
Crazy Horse

USA
516 Posts

Posted - 22 Jul 2019 :  4:07:15 PM  Show Profile  Reply with Quote
Thanks Steve. If I could find a stock looking valve cover I would consider going that route for now. I know the stock valve covers are going to be a pita compared to something with more room.

All the power should be in by 5500- 6000, with the RA manifolds and the egr era ported intake I do not see it going past that. That is were I am starting anyway. My goal is to keep it stock looking down to the right part numbers and see what it is capable of. Jay
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Corncob2061
Crazy Horse

USA
516 Posts

Posted - 22 Jul 2019 :  4:17:06 PM  Show Profile  Reply with Quote
I can cut the spring seats a little deeper, as is with the compcams 940 retainers it about 1.75 with nothing cut. Those Howards say 175 lbs at 1.75. I have never used anything from Howards before. The 914 comps are 1.8 and I would probably have to shim them some to get to my 170-180 seat pressure I am looking for. Jay
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Corncob2061
Crazy Horse

USA
516 Posts

Posted - 22 Jul 2019 :  4:31:08 PM  Show Profile  Reply with Quote
Actually the exhuasts are 1.78, the intakes are 1.73 with the 940 retainers.
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Steve C.
Chief PONTIAC

2038 Posts

Posted - 22 Jul 2019 :  4:33:50 PM  Show Profile  Reply with Quote
This will be of interest ( If the site is up and running ):

https://forums.maxperformanceinc.com/forums/showthread.php?769282&p=5353883#post5353883
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Steve C.
Chief PONTIAC

2038 Posts

Posted - 22 Jul 2019 :  4:39:28 PM  Show Profile  Reply with Quote
Just watch your distance from coil bind.

"Anything more than 0.150 inch may cause spring surge, which can greatly reduce the available spring load needed to close the valve."

https://www.hotrod.com/articles/how-much-valvespring-coil-bind-clearance-is-safe/

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Steve C.
Chief PONTIAC

2038 Posts

Posted - 22 Jul 2019 :  5:12:16 PM  Show Profile  Reply with Quote
Jim Butler has a good selection of valve covers that are plain and a bit taller. Some people just use a spacer between the valve cover and the cylinder head, but you may not like the appearance. And naturally you can have the potential of brake booster interference to deal with.

Recommended:
http://jomarperformance.com/catalog/index.php?cPath=21_22_30
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Steve C.
Chief PONTIAC

2038 Posts

Posted - 22 Jul 2019 :  5:20:07 PM  Show Profile  Reply with Quote
Also won't your roller rocker arms require a taller valve cover anyway. It's my understanding Pontiac Factory Height Valve Covers Cannot Be Run On Engines With Roller Rockers.
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tjs44
Crazy Horse

USA
620 Posts

Posted - 22 Jul 2019 :  7:27:58 PM  Show Profile  Reply with Quote
I run H&S 1.65 roller Rockers and 400 lobe lift with factory covers and the thick 5/16 gaskets.JMO with solid rollers error on the high side on seat pressure.Tom
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Corncob2061
Crazy Horse

USA
516 Posts

Posted - 22 Jul 2019 :  8:53:53 PM  Show Profile  Reply with Quote
Steve I know the crane gold 1.65 rockers I have will not clear the stock valve covers. The trunnion is to high and the polylocks hit the valve covers. H&S must have the trunnion lower. Thanks for the links, I will check them out.

Tom do you recall if your running the poly locks that Harlan Sharp provides with their rockers?

I am leaning toward 1.7 H&S rockers.

I am going to run a isky rev kit too. Jay

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Steve C.
Chief PONTIAC

2038 Posts

Posted - 22 Jul 2019 :  10:42:32 PM  Show Profile  Reply with Quote
Keep in mind the Harland Sharp 1.65 rocker arms for Pontiac will measure closer to 1.684 ratio, and some suggest even closer to 1.7

Isky used to make a Rev kit for Pontiac, but that was back in the dark ages. Curious, with the popularity of roller cams has it changed for a Pontiac specific application, or will you have to fabricate/adapt ?
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tjs44
Crazy Horse

USA
620 Posts

Posted - 22 Jul 2019 :  10:53:30 PM  Show Profile  Reply with Quote
I ran the supplied H&S polys.What studs are you running?Maybe they are the issue?Tom
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Steve C.
Chief PONTIAC

2038 Posts

Posted - 22 Jul 2019 :  11:08:19 PM  Show Profile  Reply with Quote
"My son Steve was a street racer for years, and he drove some serious race engine stuff on the street. I do feel that a rev kit is the best possible thing for this if they make one for your engine. Old man Isky himself told me that they would increase the life of the roller bearings by 5 to 10 times normal street life."
JOE SHERMAN RACING ENGINES

Another caviet, that statement was made in a discussion with the use of a serious solid roller cam. Also this was quite some time ago when splash lube was important, now today we have solid roller lifters with direct oiling to the roller lifters. This aids in the life of a solid roller lifter on the street.


Edited by - Steve C. on 22 Jul 2019 11:20:37 PM
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Corncob2061
Crazy Horse

USA
516 Posts

Posted - 23 Jul 2019 :  12:39:27 AM  Show Profile  Reply with Quote
The brackets for the rev kit are old just like described. There are only certain lsky lifters it works on, as far as I know all the lifters are Isky. The link bar is different across the top and has provisions for the rev kit springs. They are Isky sbc lifters with Pontiac link bars. I have read the rev kits can cost some power, but they are known to extend the life of the lifters on a street engine, even the pressure oiled are suppose to last longer with them. We shall see..

Last couple sets of studs I have done came from Butler. But I have also used BBC arp rocker studs and shortend them.

I am wrong that I could not run the crane roller rockers with stock valve covers. I had forgotten we did that with a stockcar engine that was required to run stock valve covers. Somehow we made it all fit. But I do not recall now what we did to run them. We might have shortened the polys and studs. We tried using a set of cranes last winter on a ram air 3 valve cover and the did not clear with studs from butler and the polys we had. It sounds like the HS rockers might have more clearance. Jay

Edited by - Corncob2061 on 23 Jul 2019 12:40:28 AM
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tjs44
Crazy Horse

USA
620 Posts

Posted - 23 Jul 2019 :  11:22:30 AM  Show Profile  Reply with Quote
Have you bought the 5/16 gaskets from Butler?That made the diff in all my engines.Tom
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Corncob2061
Crazy Horse

USA
516 Posts

Posted - 23 Jul 2019 :  2:41:29 PM  Show Profile  Reply with Quote
My OH gasket set came from Butler. But the valve cover gaskets were not the 5/16. They already got robbed for that ram 3 valve cover last winter, so I need a set anyway. I will get definitely get set of the 5/16 from Butler for this.

The roller lifters I have for the rev kit not pressure lubed. They are splash lubed. Sorry, that was confusing how I wrote that last post. What I have are not anything special. Jay

Edited by - Corncob2061 on 23 Jul 2019 2:44:57 PM
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Steve C.
Chief PONTIAC

2038 Posts

Posted - 23 Jul 2019 :  3:25:59 PM  Show Profile  Reply with Quote
"Now as you might imagine, a race roller camshaft setup is naturally going to make more power as it has a much more aggressive ramp rate than a street camshaft. The trade off comes from higher spring pressure, decreased durability from a street application, and the higher spring pressure can induce extra wear in the roller lifters, especially at idle."

"A street roller cam is designed with a less aggressive ramp, requiring less spring pressure, putting less strain on the roller lifters at idle when the oil pressure is low and the lifter gets only splash lubrication. Our test involves two street roller camshafts, as opposed to racing camshafts, and while just about any cam will work on the street, you run the risk of wearing your lifters out prematurely with the wrong setup."

Enter into the equation solid roller lifters with hi pressure direct oiling to the needle bearings for improved cycle life.
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Corncob2061
Crazy Horse

USA
516 Posts

Posted - 23 Jul 2019 :  10:26:46 PM  Show Profile  Reply with Quote
I emailed isky about this cam, never heard back from them, probably needed to talk to someone there. The number for the isky cam is

RR-505C62

We have had this isky cam since the late 1990s, it came out of someones 69 ram air 4 gto, I had it in a 455 for awhile but pulled it out and switched cams before I ran it. I assume the cam was ground in the 80s.

On the ends of the cam, engraved in amazing looking cursive for using an engraver. It says:
285M
Magnum
Iskenderian
6L. 115
RR-505C62
901

It would be worthwhile to post a picture of the engraving on the cam. Lol, it is art..

I have the cam card, it is hand written in. Funny thing, it says it has .317 tappet lift, but .48 at the valve. But .317x1.5=.4755, guess they did some rounding. Maybe this could be much older than 80s. Always been some what of a mystery.

This idea to try using this cam is pretty new, been thinking about using it for about a week. As much fun as it would be to use this old cam. Money wise, it would not be much more to not buy new rocker arms, use the crane gold 1.65s I have, and buy a new cam that has more lift. I get this cam out every couple years dreaming about putting it in something.

Steve thought he had an old Isky book. For entertainment and nostalgia, anyone speed Iskenderian?

Jay



Edited by - Corncob2061 on 24 Jul 2019 02:21:30 AM
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Corncob2061
Crazy Horse

USA
516 Posts

Posted - 24 Jul 2019 :  12:59:24 AM  Show Profile  Reply with Quote
Check out the engraving someone did. I am use to reading chicken scratches on the end of cams :)

[URL=https://imageshack.com/i/pnmvrTuWj][/URL]

Edited by - Corncob2061 on 24 Jul 2019 7:36:47 PM
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Corncob2061
Crazy Horse

USA
516 Posts

Posted - 24 Jul 2019 :  02:08:22 AM  Show Profile  Reply with Quote
I went up to Rocky Rotellas last winter with friend and tested a 70 replacement ram air 4 head and it had terrible reversion after it hit .5 lift. Great low lift through .4 lift numbers, peaked at .5. The production head made it to about .55 and never showed reversion like the SR head. But the SR head was 20cfm higher at .3-.4 lift. This isky cam with 1.65s would have been a monster with that ram air 4 SR head. Maybe Ed knew what he was doing, it was last in a RA IV.

I would like the cam to be closer to .6 lift. This engine has 6x-4 heads. Intake ports are 190. They started out at about 158cc. I will have to see if I can get Rocky to flow them before I bolt them on. Our flow bench was back in the corner of our shop and accidentally I backed into it with a skid loader. Grrrr.

Maybe I need to do a cam scavenger hunt at Norwalk! Jay



Edited by - Corncob2061 on 24 Jul 2019 02:35:39 AM
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Steve C.
Chief PONTIAC

2038 Posts

Posted - 24 Jul 2019 :  11:29:49 AM  Show Profile  Reply with Quote
My Isky catalog is from 2005
The number 901 indicates it was ground on a journal diameter used for a Pontiac application. Within the Pontiac section of the catalog the solid roller cams start with "RR" on the grind number. There are only five Solid roller grinds listed in that section, smallest rated 260 at .050" and .602 valve lift. All listed with a 108 lobe separation, which is very typical with Isky lobes. In the back of the catalog within the lobe specification chart with different lobes there is no solid roller lobe listed with a .3170" lobe lift. The smallest is .3230" on a street roller with 234 degrees at .050".

All the Isky Pontiac solid roller cams listed are listed to use their 9265 spring rated 175 at 1.875". And use a bronze dist gear.

Here is on line info:
http://www.iskycams.com/userfiles/files/ISKY-Master%20Lobe%20List.pdf

Even with a higher rocker arm ratio with that small lobe lift and after .028" lash the low net valve lift will not take advantage of your ported cylinder heads. Which could flow upwards toward .600" lift. My race ported factory d-port heads did not go into turbulence until about 0.650" lift.


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Corncob2061
Crazy Horse

USA
516 Posts

Posted - 24 Jul 2019 :  1:28:56 PM  Show Profile  Reply with Quote
Thanks for finding that info Steve. Finding info on the Isky web site is like trying to fly a kite in a tornado.

I see Lunati has a solid roller 290/290 248/248 .555,.555 street grind cam with a 112 lsa. That would be. .610 lift with the 1.65, if I was set on the specs of that isky that lunati would be a better choice.

I think I will do a split duration cam with a little less overlap, widen the lsa out more, then shoot for .6 lift. Trying the work with the ported stock intake and the RA manifolds. Jay
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Steve C.
Chief PONTIAC

2038 Posts

Posted - 24 Jul 2019 :  8:22:39 PM  Show Profile  Reply with Quote
"Finding info on the Isky web site is like trying to fly a kite in a tornado"


The current Lunati web site is not much better. It has gone down the crapper!

A few days ago I called and talked with a tech person about the fact they removed the information regarding the different lobes from their website. You can only get information if you have a specific cam in mind. He even agreed the section listed for specific information on their voodoo line is limited, and quote "there are 'glitches' within their website" ..... but said they are working on it ! I then asked if the had a catalog to mail out with different lobes listed... no, nothing available !

.
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Steve C.
Chief PONTIAC

2038 Posts

Posted - 25 Jul 2019 :  12:34:17 PM  Show Profile  Reply with Quote
Changing rocker arm ratios?

This calculator will determine what the new lash
should be for the new rocker arm ratio.

http://www.wallaceracing.com/calc-lash.php
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Corncob2061
Crazy Horse

USA
516 Posts

Posted - 11 Aug 2019 :  11:24:14 PM  Show Profile  Reply with Quote
Going to add some edits here for another Isky cam we have. I thought this was cool for an engine that was built in 1963 or 64. Dad graduate in HS 66 and he remembers the heads in shop class having the rocker studs pinned when he was either a freshman or sophomore. I was going through my engine record book and I happened to come across the specs to this cam, it is what had that rev kit on in originally. It was in a 1960 Bonneville with a 389. I think this cam was ground in 1963 or 1964. We ran the cam is a 350 race car, it ran great with 1.5s, but but when we put 1.65 on it we bent several push rods and wiped a couple lobes. Probably the push rods were not heavy enough or the big valve heads on the 350 had some valve clearance issues. If we would have had the rev kit on it it might have survived. IRC, the rev kit was hitting the valley cover and we could not run it. I remember it sounded totally wicked. Looks like it would be another candidate for big ratio rocker arms if it was fixable.

These were the specs I measured at .022 lifter rise and .050 back when I built the 350 in 1998......if you like nostalgia, here it is:)

Duration at .022 tappet
Intake
300*. IVO 42, IVC 78
Exhaust
300*. EVO 84, EVC 36

Lobe lift intake
.327

.050
Intake 256
Exh. 256
.325 lobe lift

I have no idea what it may have been rated at originally. The old 389 had domed pistons with closed chamber heads, offy tri power and homemade fender wall headers. Cool old engine inside and out. Was a lot of cam in a 350. :) jay





Edited by - Corncob2061 on 12 Aug 2019 11:44:03 AM
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