Not enough octane? what you guys think?

gts340 said
If your not pinging, and your sure, then you don't need higher octane fuel. Higher octane fuel will actually produce LESS horsepower than lower octane fuel because it burns slower.

this is exactly what my reasoning was

EL5DEMON340 said
if it don't ping /run on/ deisel on 89 use it. higher octain burns slower, so you would have to add more timing. the old trw pistons are rated at bluprint specs and are usually much lower in a real production block, add the much thicker felpro gasket on to that and i bet your CR is more like 9 to 9.5.

i figured that im not getting a true 10.5:1 as thats just what the piston was advertised at...thanks for the info!

HemiMark said
Hey Dude, read this http://www.wanderings.net/notebook/Main/IsHighOctaneGasWorthTheMoney
and then go buy some 91 or 93 and see if it makes a difference......... I use 93 just because.........and every once in a while I use octain booster...

I dont get it, that article proves what i already think, that i dont need the higher octane gas...my engine is not pinging, so how would the 91 help? i dont know if the dealer called for 91 from the factory or not, so it seems like the lower the octane that works the more cents it makes (pun intended lol)

redfastback said
I agree. No 10.5:1 iron headed engine can run on 89 unless you have severely retarded timing. Do a comp test and get some PSI #'s. That will give you a better idea of your static compression. I bet if you installed an MSD dist, with the 18* bushing, 2 light blue springs, and set your initial at about 16*, and add 91, your gonna run alot harder than you do now.

No it will not feel like nitrous....lol.

Well like i said, its got stock x heads with trw replacement 10.5:1 pistons, so im not 100% sure what my true compression ratio is. I will have to do a compression test. I have a mopar performance electronic distributor and right now initial is set at 16 and total at 36...id rather not change distributors, but i am going to try and weld up the slots in the distributor to get something closer to 19 or 20 initial (i have heard this would be beneficial)...i think when i do this i may have to up to 91 octane, but all in due time i guess