91 octane and high compression.

Whats the highest compression you can run on 91 octane without detonation? I ask because im buying high compression pistons/rods soon for b18c1 and am wondering whats possible and whats not… Thanks

There are a LOT of factors, every build is different and tuning plays a large role. My buddy’s car was 12:1 and it ran on 91 but had to be massively detuned in order to run safely at that compression. Seems the general consensus is that somewhere right around 11:1 is where you want to be. That’s what I’m running and it’s been fine thusfar.

Thanks thats kind of what i was hearing… Ill stick with 11:1 then… And focus more on top end power.

What do u think of a 4.7fd in a hydro b16 tranny? Ever heard of that combo?

I’m not a fan of hydro transmissions in EF/DA chassis. But as for gearing, you just need to see what gearing you like and use the calculator to see what that combo would do for you. My friend’s 4.7 in a GSR YS1 is a little too short for his liking, but my 4.7 ITR gearing is great, actually I wouldn’t mind slightly shorter. Really it’s personal preference as well as what the car is going to be used for.

Yeah i hear you. Right now its a 4.4 and i like it wit all b16 gears… I bet ur trannies nice if im not mistaken b16 1-3 gsr 4-5 and a 4.7. I agree id rather have a cable housing… I live down the street from willow springs and i hit quarter miles every once in a while. Other than that its a weekend cruiser… Im planning on a motor teardown and chassis restrengthening on top of hopefully adding LSD. I expect this could take up to a year so im trying to get key parts figured out now to buy.

Have u had ur car weighed?