High Comprression Engines vs 92 Octane Fuel

[Fred]

high comprression engines vs octane fuel fred i'm currently building a hp motor for my ' roadster and am concerning about the compression ratio pistons required by the specs i've read that high compression engines need at least octane to run and not damage the engine is anyone running a high compression engine on octane fuel if so how is the performance additionally would the fuel additive octane be of any viable use thanks for any help on this matter best regards fred

[John H.]

Re: High Comprression Engines vs 92 Octane Fuel

re high comprression engines vs octane fuel john fred if you want to be absolutely authentic and stick with you'd better get used to buying octane low lead at your nearest airport in gallon cans and filling up from them that's the only way you're going to survive these days at compression suggest you invest in a teardown and a set of dished top pistons while you're at it have exhaust valve seats installed in the heads now you can fill it up with octane not have to carry around plastic bottles of and lead substitute set the timing where it belongs and run hell out of it without having to deal with detonation my john '

[Joe L.]

Re: High Comprression Engines vs 92 Octane Fuel

re high comprression engines vs octane fuel joe lucia i do not believe that or octane gasoline will support compression i've had a difficult time making it work with my of course your has lots of cam overlap which reduces cylinder pressures and it is possible that you might get away with it but i doubt it if you wish to keep your compression you have several options using racing gasoline very expensive and inconvenient use octane aviation gasoline which is actually higher than octane on the r m automotive octane scale illegal expensive and inconvenient use octane boosters like these work but to produce acceptable octane boost you must use a lot of it this can get very expensive if you drive the car much if you drive it minimally this will work great

[Jack H.]

Re: High Comprression Engines vs 92 Octane Fuel

re high comprression engines vs octane fuel jack humphrey fred have ' sb which was first year of cr drop and lead free fuel use when engine was rebuilt i changed internals from factory to ' and earlier cr living at feet altitude does wonders for obviating the need for high octane fuel because there's simply too little o here to fully charge the combustion chamber and most jet their carbs back a notch but i've taken the car touring and gone back to sea level here's my experience at high altitude car runs fine off octane pump gas you don't say where you plan to operate the car so i had to toss in this zinger near sea level most pumps advertise higher octane blends to meet local needs and octane was plentiful in the midwest where i was touring this just bearly cut it no detonation knock but did run satisfactorily as others have advise additives can be expensive but do turn a trick i was able to get by with octane pump when higher precision fuel was not available with a pint of octane boost additive mfgr plug deleted as much as how you jet carb for idle set timing both static and dynamic advance and how aggressive a cam you select lift overlap will affect your use need for fuel precision some guys go whole taco and build the cr out to the hilt then push the timing fuel mixture and build in something like a full race cam and try to cruise the local streets unwise zora only designed 'em this way when they were destined for off road read that race track use where wide open throttle was the norm and full race fuel was available so i'd consult with local ncrs chapter members if you aren't in a chapter get on with joining and talk the pros cons for your engine your driving conditions you can have your cake and eat it too if you don't go over board here

[Fred M.]

Re: High Comprression Engines vs 92 Octane Fuel

re high comprression engines vs octane fuel fred thanks to the many respondants your view points are well taken just want to let you all know i appreciate you taking time to answer my questions fred

[John Fulton 29200]

Re: High Comprression Engines vs 92 Octane Fuel

re high comprression engines vs octane fuel john fulton i run octane in both of my cars a solid lifter engine and my i have been doing this all summer and i have not heard a knock a ping anything the cars both run fine with no problems i do put in the lubricrant lead substitute but thats cheap the brand is exxon gas

[Jeff Grice]

Re: High Comprression Engines vs 92 Octane Fuel

re high comprression engines vs octane fuel jeff grice fred i have an original bb i run with lead additive and octane boost absolutely no problems with ping etc jeff