tuning for pump gas

[bubba_zenetti]

correct me if i am wrong but it is my understanding that it is possible to run 92 octane pump gas on low boost setups.

what i am wondering is what is a safe combo of comression ratio, boost, and timing retard for a 92 octane run bike?

i am thinking a set of low compression j&e turbo pistons would be the safest thing to do, but i do hear about kits that are designed for a totally stock engine. what are your thougths guys?

 

[69ls1]

6 pounds of boost for pump gas. You can run more boost with a spacer, turbo pistons, intercooler, or water injection. IMO, Start low and get the basis first.

 

[rocketgeezer]

69s right 6 lbs boost is about all you want with stock comp, JEs and spacer you can get to 10-12 for short bursts, for longer runs you will at least need water injection and more boost than 12 you will need more fuel than your stock injectors are capable of, some guys go bigger injectors, sometimes hard to tune, or a secondary set of injectors runs very well when set up properly but a bunch more money

 

[exzx]

stock motor is pretty tough. it can take 8lbs all day. you can run water injection and go even higher on pump gas.

 

[bubba_zenetti]

what about timing at 6psi? any need to pull out or not.

my goals for this bike is to get at least 210rwhp or maybe more and have it a run on pump gas on long distance rides with no fear of melting anything.

 

[turbobusa2000]

If you run turbo pistons with the spacer and only 6psi you'll be able to run all day man. Just make sure your a/f ratio is set up properly. I rode around on a bone stock bike with a 6psi kit for two years and I never had it on a dyno until it took a crap last fall. It probably would still be running if I had the a/f set up right. So make sure its on a dyno that's the key to making it reliable for the long haul.

 

[bubba_zenetti]

on another note, what is a safe a/r to shoot for on 6psi? i would assume the lower 13s would be rich enough to keep it from preignition without becoming a plug fouling pain in the ass.

unfortunatley, i do not have a dyno at my shop so i am going to have to rely on data logging with a wideband at the track so set my a/f ratios.

 

[cdhoroho]

11.8:1 for turbo applications

 

[boosted]

11.8:1 for turbo applications

+1 especially over 6-7000 rpms.

 

[bubba_zenetti]

wow, that is pretty fat.
i ran my wrx at 13.1 and nothing melted.

is plug fouling a problem running that fat?

 

[kawiboy11]

this aint no wrx!

 

[MET]

You should run at least 93 octane. 94 95 if you can get it. higher the octane the slower the burn. Be save if you are really going to ram it put in some good octane boost also.