I'm building a b20z non-vtec with crower 404's, aftermarket pistons and rods. But i still don't know what compression i should go. Also, i'm running a wet nitrous kit at about 75 hp. Is 11.1:1 is too much? Would i be fine with that compression and get like 4 degrees of retard when spraying? Maybe 10.5:1 would be better?

I wanna hear the high comp. and nitrous users, thanks

 

i would go with the 11:1........because over time you will probably eventually get sick of the nitrous and want to stick with N/A so the more CR the better.........just pay close attention to tuning with a 75shot and 11:1CR

if it was up to me i would go with 12.5:1 and no nitrous......


[Modified by non-VTEC, 12:16 PM 9/14/2002]

 

right on....i hate vtec....keep on eye on your compression with the bottle i have heard some stories. get the com tested in each cylinder like 2 or 3 times...

 

Thanks for the quick answers guys. But what should i get or look for to avoid detonation with such a high compression engine? Cause right now, i have a stock b18a with a 50 shot and it's running perfect with stock timing. Plugs are perfect color, no detonation at all.


[Modified by xxplosif1, 1:13 AM 9/15/2002]

 

If you talk with poeple who build engines specifically for nitrous use i.e. drag race engines, they build them with high compression. The engines are much like a built N.A. engine, with cams designed for nitrous. High compression and nitrous are fine. It isn't boost, it is an oxygen rich mixture.

 

All the good nitrous engine builers I know never exeed 12:1 comp and if possible flat top pistons (Billy Glidden for one)
Phil all you needed was to ask and you get
By the way Phil I'll be selling good gas for all O2 sensor equipped cars

 

thanks for all your answers guys

TK

 

t t t

 

I don't run NOS so take my words with a grain of salt, but I believe it's typical to richen the mixture when you're spraying, which would make sense since you're cooling the intake charge with NOS and getting greater volume, more air, and therefore more heat. Sounds like you already have an idea of what you're doing. I'll probably be in the same boat as you. I have uninstalled pistons to make my car 11.3:1, but willl probably use flat valves to boost this to near 11.7:1. Not sure if NOS is in my future, just keeping my options open.