older high compression engines
Thread Starter
Race Director
Joined: Sep 2005
Posts: 18,640
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From: Farragut,TN
older high compression engines
I know this has been done before but where can I find teraethel lead additive for this junk gas we have today? Don't say any of the so called octaine boosters that are avaible today most of them are useless. Would like to see a grey exhaust pipe again before i die.(old school mecanic type)
Team Owner
Joined: Apr 1999
Posts: 21,953
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From: Reno Nevada
2024 C3 of the Year Finalist- Modified
Can U cypher? If you have an 18 gallon tank empty Put in 12 gallons of 93 and 6 gallons of 110 Sunoco leaded race gas. The last 55 gallon drum I picked up was only $7 per gallon
That gives you after blending 98.67 octane.
My Vette has a 25 gallon tank.
The smarter thing to do is yank out the sorry old cam and springs and put in a cam with modern lobe designs and make more power, more MPG, and run fine on 91 - 93 pump gas just fine.
That gives you after blending 98.67 octane.
My Vette has a 25 gallon tank.
The smarter thing to do is yank out the sorry old cam and springs and put in a cam with modern lobe designs and make more power, more MPG, and run fine on 91 - 93 pump gas just fine.
Melting Slicks
Joined: Mar 2002
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From: Beringen
Safety Car
Joined: Oct 1999
Posts: 4,101
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From: NorCal
George's solution is the way to go if you don't mind tearing into your engine, and you'll really like the results, but if has to stay stock, then blending race gas (or running it straight) is your best option. Here in NorCal your restricted to 100 octane unleaded for a street car. Leaded fuel can still be put in a numbered, unlicensed race car.
The tracks I frequent are all over the map on this. Laguna is very strict. A track employee unlocks the pump, you fuel your race car (no cans), he locks it up again. Track 'X' (don't want to get 'em in trouble), it's business as usual, you do what you want.
I run the 100 octane in a '63 11.5-1 vintage 'vette engine in a '88 GTA that works just fine on it, old cam and all. I agree that most over-the-counter additives are marginal at best.
Hans
The tracks I frequent are all over the map on this. Laguna is very strict. A track employee unlocks the pump, you fuel your race car (no cans), he locks it up again. Track 'X' (don't want to get 'em in trouble), it's business as usual, you do what you want.
I run the 100 octane in a '63 11.5-1 vintage 'vette engine in a '88 GTA that works just fine on it, old cam and all. I agree that most over-the-counter additives are marginal at best.
Hans
Team Owner
Joined: Apr 1999
Posts: 21,953
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From: Reno Nevada
2024 C3 of the Year Finalist- Modified
Another attempt would be to look at the dizzy.
The correct way to tim a motor is with vacuum advance disconnected and run it up to like 3800 rpm with a dial back timing light. old style heads make the most power right around 38 degrees.
depending on your advance curve it doesn't matter what idle is
This is not a hard concept
Look into some place that can recurve it on a machine. Start with a high enitial Like 12 degrees at idle and bring it in slow with the mechanical to not have full like an additional 24 till 3000 or 3200 rpm. for a total of 36.
My dizzy has only 15 degrees of mech advance and 6 vacuum Digital dizzy
My idle has 17 advance and all in at 3200 for a total of 32 degrees. with late model fast burn Dart or AFR heads
The correct way to tim a motor is with vacuum advance disconnected and run it up to like 3800 rpm with a dial back timing light. old style heads make the most power right around 38 degrees.
depending on your advance curve it doesn't matter what idle is
This is not a hard concept
Look into some place that can recurve it on a machine. Start with a high enitial Like 12 degrees at idle and bring it in slow with the mechanical to not have full like an additional 24 till 3000 or 3200 rpm. for a total of 36.
My dizzy has only 15 degrees of mech advance and 6 vacuum Digital dizzy
My idle has 17 advance and all in at 3200 for a total of 32 degrees. with late model fast burn Dart or AFR heads
Last edited by gkull; Mar 1, 2011 at 12:24 AM.
Safety Car
Joined: Sep 2003
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From: Belmar NJ
Unless I'm missing something we're talking two different things here. Changing the CAM to a roller will help you with the OIL that has been reformulated without ZINC (unless you use Rotella T, not a racing oil and even it's zinc contents have been reduced).
The LEAD acts as a lubricant for the VALVE GUIDES in the HEADS. The heads would need to come off and hardened guides put in (at this point it would be a good idea to change the cam and lower the compression for today crummy gas. I'm sure worse is coming)
While A/V gas will help with octane, there's much more to it than that. The additive package is meant to work at altitude so to run the car at/near sea level can actually damage your engine/fuel system (if you towed the car to Denver or Mexico City first, you'd probably be ok)/:\
The LEAD acts as a lubricant for the VALVE GUIDES in the HEADS. The heads would need to come off and hardened guides put in (at this point it would be a good idea to change the cam and lower the compression for today crummy gas. I'm sure worse is coming)
While A/V gas will help with octane, there's much more to it than that. The additive package is meant to work at altitude so to run the car at/near sea level can actually damage your engine/fuel system (if you towed the car to Denver or Mexico City first, you'd probably be ok)/:\
Last edited by parkerracing; Mar 1, 2011 at 03:09 AM.
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Burning Brakes
Joined: Oct 2008
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From: Jersey Shore
Unless I'm missing something we're talking two different things here. Changing the CAM to a roller will help you with the OIL that has been reformulated without ZINC (unless you use Rotella T, not a racing oil and even it's zinc contents have been reduced).
The LEAD acts as a lubricant for the VALVE GUIDES in the HEADS. The heads would need to come off and hardened guides put in (at this point it would be a good idea to change the cam and lower the compression for today crummy gas. I'm sure worse is coming)
While A/V gas will help with octane, there's much more to it than that. The additive package is meant to work at altitude so to run the car at/near sea level can actually damage your engine/fuel system (if you towed the car to Denver or Mexico City first, you'd probably be ok)/:\
The LEAD acts as a lubricant for the VALVE GUIDES in the HEADS. The heads would need to come off and hardened guides put in (at this point it would be a good idea to change the cam and lower the compression for today crummy gas. I'm sure worse is coming)
While A/V gas will help with octane, there's much more to it than that. The additive package is meant to work at altitude so to run the car at/near sea level can actually damage your engine/fuel system (if you towed the car to Denver or Mexico City first, you'd probably be ok)/:\
Race Director
Joined: Sep 2004
Posts: 11,874
Likes: 263
From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
i use the "gunk" lead additive from auto zone in my 37 ford flathead ...not for the high compression (it has 6.5:1) but for the lubrication for the 70 year old valves.
Race Director
Joined: Jul 2001
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The LEAD acts as a lubricant for the VALVE GUIDES in the HEADS. The heads would need to come off and hardened guides put in (at this point it would be a good idea to change the cam and lower the compression for today crummy gas. I'm sure worse is coming)
While A/V gas will help with octane, there's much more to it than that. The additive package is meant to work at altitude so to run the car at/near sea level can actually damage your engine/fuel system (if you towed the car to Denver or Mexico City first, you'd probably be ok)/:\
Avgas will also work fine in a car, but is also a waste of money.
The OP wants lead in his car for some unknown reason, no real easy ways of doing it and none of which are legal.
Race Director
Joined: Sep 2004
Posts: 11,874
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From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
I think you meant valve seats, not valve guides. Either way it's an unnecessary procedure and waste of money.
Avgas will also work fine in a car, but is also a waste of money.
The OP wants lead in his car for some unknown reason, no real easy ways of doing it and none of which are legal.
Avgas will also work fine in a car, but is also a waste of money.
The OP wants lead in his car for some unknown reason, no real easy ways of doing it and none of which are legal.
i have never used the lead additive in any of my old cars until the flathead......after having taken apart several flat head engines and being totally frustrated by the valves i have decided on this engine to make sure it has the lubrication. if the valves were not mounted in the block i would not be using it.
Race Director
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i have never used the lead additive in any of my old cars until the flathead......after having taken apart several flat head engines and being totally frustrated by the valves i have decided on this engine to make sure it has the lubrication. if the valves were not mounted in the block i would not be using it.
Corvettes from approx. 1970 and up came factory equipped with hardened valve seats even though it turned out that this was unnecessary. The concept of the lead providing 'lubrication' to the guides or seats is incorrect. The lead provided a sacrificial layer or coating of metal to reduce or eliminate microwelding between the valve face and seat. That's it.
Melting Slicks
Joined: Feb 2004
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From: State of Confusion!!!
2018 C2 of Year Winner
Check out a company called KEMCO Oil...I think.
It used to make Octane Supreme 130. It was supposed to have the real TE Lead in it. I used it in my '68 327/350 and it really did work. I was able to put more timing in it without detonation You could even smell the "old style real gas" smell coming out the pipes.
It used to make Octane Supreme 130. It was supposed to have the real TE Lead in it. I used it in my '68 327/350 and it really did work. I was able to put more timing in it without detonation You could even smell the "old style real gas" smell coming out the pipes.
Racer
Joined: Jan 2008
Posts: 295
Likes: 58
From: Arvada Colorado
older high compression engines
There is a true tetraethyl lead additive. It probably is not street legal but it works. I use it to make my own race gas and have done so for years. I originally found the idea on a circle track racing magazine. The stuff is available on the internet. Anything that you can find in the local auto store does not work for racing applications. I need both an octane boost and lead for the valves. The octane boost is required because of the advanced timing needs of the engine and the 13:1 compression of the motor. Octane boosters will not provide any more horesepower on their own and, in some circumstances may hurt horsepower. The stuff is called Octance Supreme 130.
Race Director
Joined: Sep 2004
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From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
I was referring to Corvettes, which is what the OP asked about. The Gunk product contains no actual lead- which is what the OP asked about.
Corvettes from approx. 1970 and up came factory equipped with hardened valve seats even though it turned out that this was unnecessary. The concept of the lead providing 'lubrication' to the guides or seats is incorrect. The lead provided a sacrificial layer or coating of metal to reduce or eliminate microwelding between the valve face and seat. That's it.
Corvettes from approx. 1970 and up came factory equipped with hardened valve seats even though it turned out that this was unnecessary. The concept of the lead providing 'lubrication' to the guides or seats is incorrect. The lead provided a sacrificial layer or coating of metal to reduce or eliminate microwelding between the valve face and seat. That's it.
Team Owner
Joined: Mar 2003
Posts: 26,118
Likes: 1,873
From: Greenville, Indiana
I was referring to Corvettes, which is what the OP asked about. The Gunk product contains no actual lead- which is what the OP asked about.
Corvettes from approx. 1970 and up came factory equipped with hardened valve seats even though it turned out that this was unnecessary. The concept of the lead providing 'lubrication' to the guides or seats is incorrect. The lead provided a sacrificial layer or coating of metal to reduce or eliminate microwelding between the valve face and seat. That's it.
Corvettes from approx. 1970 and up came factory equipped with hardened valve seats even though it turned out that this was unnecessary. The concept of the lead providing 'lubrication' to the guides or seats is incorrect. The lead provided a sacrificial layer or coating of metal to reduce or eliminate microwelding between the valve face and seat. That's it.
Reading the OP's post, it looks like he's searching for higher octane. Hard to tell. It's also hard to tell why he'd need anymore than 91 or so octane for his engine unless someone has made some unapproved modifications to it!
Race Director
Joined: Jul 2001
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I think you have your hands full with this bunch, Mikey!
Reading the OP's post, it looks like he's searching for higher octane. Hard to tell. It's also hard to tell why he'd need anymore than 91 or so octane for his engine unless someone has made some unapproved modifications to it!
Reading the OP's post, it looks like he's searching for higher octane. Hard to tell. It's also hard to tell why he'd need anymore than 91 or so octane for his engine unless someone has made some unapproved modifications to it!
Thread Starter
Race Director
Joined: Sep 2005
Posts: 18,640
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From: Farragut,TN
When I posted origanally i stated that the octaine boosters didn't boost octaine that much it is a waste of money. the thing I was asking about was terraethel lead additives. I would to like to tune the original engine as I could have done in 1969 without swapping cams etc as I have a # matching engine. I also miss the grey exhaust pipes from that era. The car isn't driven that much and I don't have to worry about emissions.