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Paul
Sitting Bull
USA
121 Posts |
 Posted - 02 Mar 2010 : 12:57:50 PM
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| what fuel octane will be needed for a 455 with a compression ratio of 11 to 11.5? I have read that octane boost bought from a can is no good. is this true or is there a way to boost pump gas? |
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Bill Boyle
Horse Feathers (Charter Member)
USA
1593 Posts |
Posted - 02 Mar 2010 : 3:37:23 PM
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Paul, with that level of static compression, you will need to run 100 unleaded octane racing fuel or a mixture of unleaded racing fuel and premium unleaded 92-93 octane to avoid detonation.
As for octane booster additives, they really do very little to improve combustion so as to thwart detonation. |
"Dedicated to keeping the classic Pontiac engine alive."
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Edited by - Bill Boyle on 02 Mar 2010 3:40:44 PM |
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PontiacMatt
Cochise
USA
659 Posts |
Posted - 02 Mar 2010 : 4:07:28 PM
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| Iron Heads? |
*72' Pontiac Lemans* - Work in Progress |
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Paul
Sitting Bull
USA
121 Posts |
Posted - 02 Mar 2010 : 5:11:39 PM
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| oh yea #13 iron heads |
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RayK
Cochise
USA
552 Posts |
Posted - 02 Mar 2010 : 7:58:57 PM
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We ran casting #12's and casting #670's on the Bird with a 462 for a few years and are running #62's now. We ran 110 octane Marathon racing fuel all the time. Funny thing is though that when the 670's were on it, we mixed the racing fuel with 93 octane and dropped a few degrees in timing we gained a little over a tenth in the 1/4. Agree with Bill though that you need no less than 100 octane in your combination.
When we tried the octane booster it did absoltely nothing to stop detonation so I put two cans in and it still did nothing to stop detonation. It must be whale piss in a red can or something because it didn't work. |
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Brian R
Cochise
USA
862 Posts |
Posted - 04 Mar 2010 : 10:19:52 PM
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Most octane boosters are Toluene.
Toluene is 114 octane.
Do the math...
10 gal of 92 octane gas
add 3 gal of 114 Toluene
final octane is 97.07
formula is:
10 x 92 = 920
3 x 114 = 342
920 + 342 = 1262
1262 / 13 = 97 octane
This clearly shows why a pint or 2 of octane boost is a complete friggen scam. I have been telling people this for years - you might as well spend the money on a pint of Jack Daniels and pee it into you tank. At least then you'll get a buzz....lol
I used to add 3 to 4 gallons of Toluene to a tank of Sunoco 94 when you could still get it. Car ran great and a gal of toluene was about $4.00 then. It's around $14.00 a gallon now - no way. Building a new engine one of these days, dropping compression to nothing higher than 9.2 to 1. Some say I can go a bit higher but who knows how much longer until the best gas you can get is 89 octane.... I watched it go from 94 to 93 to 92 in a 4 year period.
I wish they still made the old gas .... Race gas is too expensive and I'd have to drive 30 miles round trip to get it, not worth it.
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mike mcarthur
Pony that Jumps
USA
1303 Posts |
Posted - 04 Mar 2010 : 10:23:07 PM
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| I was running that mixture in the Goat a few years ago. Ran great but the stuff is too expensive now. The new engine with reduced CR is on the stand waiting on me. |
It's the stuff you learn after you know it all that's important |
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Brian R
Cochise
USA
862 Posts |
Posted - 04 Mar 2010 : 10:28:58 PM
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I hear you well Mike.
One other thing - I always used to ignore this kind of stuff but not anymore having a brother with Hogkins Disease (Cancer)
Toluene is EXTREMELY high on the cancer causing chemical lists. No hype on that one - it's nasty damned stuff. |
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Vid
Cochise
USA
581 Posts |
Posted - 05 Mar 2010 : 12:04:03 AM
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Brain thanks for that formula, it is really helpful. I run a mix of 50% 92 premium pump gas and 50% 100 octane race gas. The race gas out here in Riverside, CA is available at a few surprisingly convenient locations near me and runs between $7 and $10 per gallon.
Back in the mid/late '70's when school was out for the summer I had a job at Moroso (when they were in Stamford, CT) bottling (canning actually)their version of octane booster, a chemical called Aniline. I would pour the Aniline from 55 gal drums into 1 gal, 1/2 gal or quart size cans. It too is nasty stuff. We had to wear eye protection, thick rubber gloves, and a heavy duty respirator. Every now and then, a supervisor would come by and look at my lips. If my lips were turning slightly blue, I had to take a 30 minute break. WTF?!
I remember someone who worked there bragging that they bought the Aniline in such large quantities, Moroso paid just $28 per 55 gal drum of the stuff and sold it in the Moroso branded cans at speed shops for $20 a gallon retail. Many years later when I was managing a drive-in movie theater, I calculated that for each case of bottled water I bought for $3.99 wholesale, it netted over $50 retail. I thought "If I can turn $4 into $55 with each case of water, that is almost as good as Moroso with their Aniline", LOL. Ah, capitalism. |
""I'll get around to that NEXT weekend..."
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Paul
Sitting Bull
USA
121 Posts |
Posted - 05 Mar 2010 : 07:03:17 AM
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| Thanks for the formula. after a few tanks of fuel maybe it would have been cheaper to buy a super charger/nitris setup in the long run! lol |
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Brian R
Cochise
USA
862 Posts |
Posted - 05 Mar 2010 : 09:33:09 AM
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Let's make it real ugly....
Clean(?) formula:
a = gallons of gas
b = octane of gas
c = a x b
d = gallons of Octane Boost
e = octane of octane boost
f = d x e
g = total gallons used (a + d)
h = c + f
i = h / f
answer from i gives you the octane
Ugly formula: example
11 gallons of 92 octane gas (a)
92 octane (b)
5 gallons of Toluene (d)
114 octane of Toluene (e)
a x b = 1012 so c = 1012
d x e = 570 so f = 570
a + d = 16 so g = 16
c + f = 1582 so h = 1582
h / g = 98.875 so i = 98.9 (rounded)
final octane with this mix is 98.9
Now lets keep it interesting.... yah right - lol
11 gallons of 92 at $2.90 a gallon = $31.90
5 gallons of Toluene at $14 per gal = $70.00
Result - one tank full of this formula cost you $101.90
That is $6.36 per gallon of mix
When looking at it this way, it is easy to see that if you drive this car much at all, new heads will pay for themselves in short order....
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Edited by - Brian R on 05 Mar 2010 09:49:21 AM |
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Paul
Sitting Bull
USA
121 Posts |
Posted - 05 Mar 2010 : 10:33:06 AM
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| after a few minutes of pondering your formula, 2 Motrin Ibuprofin and 1 bayer asprin,ha ha. I knew the fuel wasnt going to be cheap, this car will be a strip once inawhile/ everyother weekend showoff car. when we built the engine it was done to learn and experiment with, a toy if you will. in time if we get tired of messing with the current setup, or fuel is no longer available,we can always retune. we restored a 67 bird years ago that came from the factory with a 400, 4 speed, 670 heads. the engine knocked ( no high octane fuel ) it got hot at Idle and engine temp would creep up alittle. befor we could really play with it we had to sell it. the car we have now is being built so we can play with the higher compressions and see how fast we can make it without blowers ect. |
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Brian R
Cochise
USA
862 Posts |
Posted - 05 Mar 2010 : 1:12:26 PM
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Paul - have a blast !
Sounds like a fun project, wish I could partake....
Enjoy,
Brian |
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Vid
Cochise
USA
581 Posts |
Posted - 05 Mar 2010 : 1:16:19 PM
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Very interesting math, Brian! Lets look further...
So the home brew runs $6.36 per gallon (or there about). Locally, I can get 100 octane Unocal 76 race gas from a pump for $8 per gallon.
If I make home brew vs the 76 gas, that is about $20 saved per 12 gallon "tankful" (I seldom 'top it off'). I don't drive the wagon much, so lets say I fill the tank 5 times per year. I would save $100 per year making toluene boosted home brew.
What does a set of aluminum heads cost? I really have no idea. $1200? Also I would need to swap in a new cam and lifters to work with the decreased compression, add $200. So say we're at $1500 for new heads, cam and necessary gaskets.
For my particular situation, it would take 15 years to pay for the heads and cam. Holy cow!! Granted, if I drove the wagon more often, the payback would happen much faster. Also, gas prices change, maybe I can find a pair of heads for less, maybe I'll start driving the car more often, etc. Quite a few variables.
For $100 a year, I'd have to say in *my particular application*, the iron heads are going to stay around for a while. Consider too the hassle of finding the toluene, plus the hazards of mixing it, and that pretty much seals the deal for me.
But it is nice to know in a pinch I can whip up some high octane gas for cheap. Whenever I venture out on a road trip I am definitely taking a few gallons of toluene and a long funnel with me  |
""I'll get around to that NEXT weekend..."
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Paul
Sitting Bull
USA
121 Posts |
Posted - 05 Mar 2010 : 1:35:20 PM
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| Brian, thanks for your home brew recepe! we will try it out for sure. I do have the 4x heads off of the 74 455, they are for sale so if we retune the engine,it will be with dished pistons. |
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Brian R
Cochise
USA
862 Posts |
Posted - 05 Mar 2010 : 3:22:25 PM
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Vid,
It just goes to show that we each have our own situations.
For me, I used to go through 6 to 8 tanks a month from late April through mid October. With the hassle of getting race gas (for me),
toluene was a great solution while it was still cheap. Now, not worth the hassle or time. Time..... isn't that the most valuable thing most of us have.
For you, it sounds like toluene is a pretty good option. Go for it - the stuff works great - truly.
One last thing, at least as recently as 2 years ago, all pump gas in America contained toluene. That said, you know it is a viable additive. It can however, in concentration as I used it, start to soften rubber lines. But hell, now a days, the alcohol content in gas is doing the same thing so...... |
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dgray
Cochise
437 Posts |
Posted - 05 Mar 2010 : 5:35:47 PM
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| If you think Toluene is "really bad stuff" you should see what else is in your gasoline. Benzene is much more dangerous than toluene and xylene is no slouch either. The most dangerous thing most people do is fuel up their car. http://www.equivashellmsds.com |
Edited by - dgray on 05 Mar 2010 5:49:47 PM |
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Phil
Great White Buffalo
3181 Posts |
Posted - 05 Mar 2010 : 5:48:04 PM
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For me it must makes alot more sense to build the engine for pump gas unless I "plan" on using Race Gas. There are plenty of successful pump gas combos around to consider.
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Bowties are for Peewee Herman |
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bnorris_74
Cochise
USA
514 Posts |
Posted - 05 Mar 2010 : 5:55:48 PM
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quote:
Brain thanks for that formula
While it's not directed at me, I get that all the time. |
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skin151
White Buffalo
USA
74 Posts |
Posted - 05 Mar 2010 : 7:47:15 PM
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| Why dont you try this approach instead of wasting money buying pump race gas at 8.00 a gallon or cooking up toluene mixtures to eleviate detonation try calling VP or Torco and buying fuel in bulk I have been doing this for 5 years now when I got pissed on how much the track was charging me for a gallon of 112... I cannot find last years bill but it was somewhere in the area of 6.20 per gallon when purchased from Torco in a 55 gallon drum thats 340.00 per drum of 112 octane race fuel. I am sure that a drum of 100 or 104 is cheaper than 6.20 a gallon so the savings could even be more than that... |
Drive it like you hate it! |
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Paul
Sitting Bull
USA
121 Posts |
Posted - 05 Mar 2010 : 8:12:59 PM
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| Im currious about what the octain level was in 1967? For our 67 bird with the 400 it had flat top pistons with valve reliefs, c.r. had to have been around 10 maybe 10.5 to 1, with the original 670 heads. octane would have been around 100? i know a guy who delivers fuel, he said he could get me racing fuel, maybe I could get it in bulk. I will ask next time I see him. |
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Brian R
Cochise
USA
862 Posts |
Posted - 05 Mar 2010 : 10:44:04 PM
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Didn't Sunoco sell 108 in the late 60's? Before my time but I remember hearing of it.
What was required then? I think the "Supreme" of the day was around 98 octane and full of good old lead.
I am currious to see what those who were driving then have to say..... |
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Mr. P-Body
Running Bear
USA
1507 Posts |
Posted - 06 Mar 2010 : 12:32:54 PM
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In 1970, I could buy 100 octane "leaded" premium at every gas station in town (SoCal). "Super Shell", Gulf "No-Nox", etc. IRRC, about $.35 per gallon...
Sonoco "260" was VERY popular back then. I believe it was 104. It wasn't available in California, though. Sunoco stations had a "blend your own" feature where you could choose the percentages of 260 versus the lower octane stuff, to "arrive" at the blend you were after.
Mixing 30% 110 (109) and 70% 93 will "yield" a "mix" of right at 100. I "like" this approach better than "boosters" because you actually get VOLUME for your money. While increasing the octane, you're also closer to a "full tank". The Union 76 100 "unleaded" is more desired for the later cars, due to the catalyst. Not available everywhere, though.
What Phil said about building to a "plan" cannot be over-emphasized. "Old school" thinking is that compression is "king". We've learned from necessity (the mother of invention...) that flow "trumps" compression. That is, a pair of heads that flow well will make more power than less-flowing heads with higher compression, even if the correct level of octane is used. This IS a "departure" from the old way of thinking, but we DO learn as we "go". I would make it "pump gas friendly" first, and then go after the power through the modern approach.
Lastly, the "tricks" of making lower octane fuel "work" in higher compression will not gain you enough to make all the hassle worth it (IMO). Retarding ignition timing to reduce "ping" only masks the problem. It also costs power and increases combustion temperature. A 9:1 engine with 34 degrees total timing will make more power than a 10:1 engine at 30 degrees total when all other factors remain the same. Cams with more overlap to "bleed off" cylinder pressure are also a "patch" and not a "fix". They do NOTHING to "help" detonation at higher revs. In many cases, they actually compound the problem.
FWIW
Jim
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Paul
Sitting Bull
USA
121 Posts |
Posted - 06 Mar 2010 : 12:41:11 PM
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| I would love to increase the flow of our heads but im not sure if there is a place close enough that can actually do it right. by right I meen be able to measure the flow in each port and dial them all in so they are the same. |
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Vid
Cochise
USA
581 Posts |
Posted - 07 Mar 2010 : 7:41:09 PM
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With all due respect to modern thinking, I like high compression. I know the arguement for lower compression and more cubes, and I don't disagree with the thinking in the least. In fact it makes perfect sense, which is probably why idiotic me is paying for race gas or toluene.
Call me a nostalgia buff but I set out to duplicate a motor that runs and sounds like they used to in the late '60's up to the mid 70's. Big lazy cam and high compression. Granted, 10.2 is hardly "high" compression but it doesn't work with pump gas in my combo.
Sure I could build a 9.2:1 compression roller cammed 472 with aluminum heads that easily runs on pump gas, makes way more torque and goes much faster. But that is not what I wanted this time around. I wanted performance the way they used to be, for better or worse. The fuel requirements represents the bad end of that spectrum.
When the GTO's 400 ultimately expires or I want something more, chances are excellent I'll be calling Jim L for that pump gas stroker motor.
Until then, pass the toluene. Oh, and as long as 76 stations take American Express
Speaking of Toluene... I am now keeping two 5 gallon gas cans "pre-mixed" in my garage. I find it easier to mix the toluene with gas like you do for a two stroke motor. I add 1 1/2 gallons of Toluene and a touch of StaBil to each 5 gal container, then fill it up with crappy SoCal 91 premium. This way I have have gas ready to go if for whatever reason I can't get to the local 76 race gas station. |
""I'll get around to that NEXT weekend..."
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Fuel Octane
