Guest Posted November 9, 2001 Share Posted November 9, 2001 I have recently started using my 1955 76-R which had languished in the garage for 22 years. I had always usedhightest ethyl since it has a comp. ratio of 10.5 to 1. Now I an using highest grade of no-lead with lead substitute and octane booster, which is pretty expensive. Will it burn my valves if I leave the lead substitute out----what do you other guys do with these High Compression old V-8s? Link to comment Share on other sites More sharing options...
The Old Guy Posted November 9, 2001 Share Posted November 9, 2001 Your car should run fine on the 93 octane available today. You do not need either the octane boost or the lead additive. The Buick blocks have a higher nickel content than most ,so they do not suffer valve recession like some engines do. I pulled an Airstream trailer all over the country with my 57 and never had a problem. Link to comment Share on other sites More sharing options...
old-tank Posted November 9, 2001 Share Posted November 9, 2001 I must respectfully disagree with The Old Guy. 20,000 miles after reconditioning the heads on one of my 55's I had burnt valves and significant exhaust valve seat recession running unleaded. (I even have a set of heads that never saw unleaded and have both intake and exhaust valve recession.) When I reconditioned the heads again I put in hardened seats. On another engine rebuild the seats were good so I used stainless steel valves. On my last 55 with the original engine I use CD-2 availabe at Wal-Mart...this is a multi-dose lead substitute.<BR>The compression ratio on the 55- 322 is more like 9.2:1...mine all run well on the mid-grade fuel...use whatever octane it takes to eliminate pinging but no higher. An engine that has never been apart may have enough lead protection on the valves and seats to last a long time...also if you drive it easy around town rather than charging down the freeway for 5-10,000 miles a year the valves and seats will last indefinitely.<BR>Willie Link to comment Share on other sites More sharing options...
The Old Guy Posted November 10, 2001 Share Posted November 10, 2001 The engineers at Buick were the ones that told me about the nickel content. I drove my 57 60,000 miles and have driven my 40 over 90,000 miles and have not had a valve problem. Perhaps it is because both of these cars were driven when leaded gas was available,and the lesd was distributed on the valves and seats. I was apprehensive about the problem a few years ago, and pulled one head from the 57 to check for recession .There was none and I reinstalled it and towed my Airstream to Key west .I wonder if the fuels in your area are different than ours,as that would explain the difference Link to comment Share on other sites More sharing options...
Guest Randy Berger Posted November 10, 2001 Share Posted November 10, 2001 question for AWBE, what did you do to your 55 Buick to raise the compression to 10.5? Link to comment Share on other sites More sharing options...
Guest AWBE Posted November 10, 2001 Share Posted November 10, 2001 h.c. gaskets Link to comment Share on other sites More sharing options...
Guest AWBE Posted November 10, 2001 Share Posted November 10, 2001 h.c. gaskets, supposedly Link to comment Share on other sites More sharing options...
Guest Posted November 10, 2001 Share Posted November 10, 2001 Old Guy ~ Back in 1984 when I was the VP of Technical Matters for the AACA, at the same time lead was being phased out, it fell to me to try to determine what was going to happen to our engines using unleaded gas.<P>I contacted Buick, and one of their powerplant engineers told me exactly what you said. Basically, "Don't worry about it. It is not an issue here."<P>I could be wrong, but if I am, he was. Link to comment Share on other sites More sharing options...
old-tank Posted November 11, 2001 Share Posted November 11, 2001 Maybe the 57's are different...maybe my heads had a reccession problem because they had hundreds of thousands of miles on them and had multiple valve jobs. On a Ford v8 in a 51 pickup the guy at the machine shop talked me out of hardened seats since those blocks already had exhaust valve inserts...after 5,000 miles I lost all of the valve lash (gap) and the engine would not run when hot ( good thing I put in adjustable lifters).... thought maybe just breakin in...adjusted the valves and 5,000 miles the same thing...using lead substitute for the last 65,000 miles with no problems. Modern engines have either hardened seats installed or a treatment to the block in the area of the exhaust valve that prevents recession/ wear . If you are rebuilding the heads install hardened seats or stainless steel valves (not both) otherwise use a lead substitute. (Or just drive it until you have a problem and then fix it)<BR>Willie Link to comment Share on other sites More sharing options...
Guest Posted November 11, 2001 Share Posted November 11, 2001 old-tank ~ I wasn't going to get into this before, but you sort of opened the door. While doing research back in 1984, I was told that Ford engines were much more lead critical than say, GM engines. What I was told was that Ford engines were designed to use the lead to cushion the valves. I do not vouch for the accuracy of that information, only repeating what I was told. ~ hvs Link to comment Share on other sites More sharing options...
Guest Posted November 11, 2001 Share Posted November 11, 2001 When was leaded gas invented? If the flathead ford was designed to run on leaded gas then why did cars have such low compression ratios in the 30's. Link to comment Share on other sites More sharing options...
Guest Posted November 11, 2001 Share Posted November 11, 2001 Tomsriv ~ Tetraethyl lead was developed by Charles Kettering in 1924 and came into general useage by about 1926-27. ~ hvs Link to comment Share on other sites More sharing options...
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