MiKeAhOwSkI

I'm looking for people actually running a boosted motor that is at 11.0:1 compression or higher. I've seen a few guys flating around with 11.5:1 but haven't found out too much information.

I'd like to know if you guys have significant trouble running pump gas, or have a lot of problems with knocking. how much boost are you managing to run on pump gas (93)?

Most people seem to love their high compression motors, but everytime I look at the high compression vs low compression turbo threads(because I searched for about 2 hours..), people are not usually speaking from first hand experience.

so if you have at least 11.0:1 CR and are on pump gas, let me know how it drives, what boost you're running etc... ! 11.5:1 turbo stories would be perfect, since that's what I will be at.

97BLACKCIVIC

Its been done, its all on the tuning but from what i know you cant boost high and most dont last to long. At least i havent heard to many that did anyways. Their was a type-r racing a viper and it was pretty fast. the viper jumped but the type-r came back fast. Maxed out 5th like it was nothin but anyways

Bump for ya

ExospeedAMcrx

Obviously the main factor in any setup is proper tuning. Any setup wont run if it doesnt have the right fuel management and tuning.

We run 10.5-11:1 compression turbo motors all the time. What we are mainly concerned about is the type of piston being used. Its best to be at least a Flat top design. dome style pistons have worked as well, proven in ITR and GSR stock block setups. but if you are building one from scratch with forged pistons. look into a size that has a flat top. usually 84mm 10.8:1 have a flat design. or 81mm 10:1 compression are flat as well.

our own race cars are on 11:1 boosting 30psi on race gas and have been working out pretty well. We've done alot of street setups with 11:1 making the usual 350-400hp street on pump gas as well. They work, its all a matter of tuning.

Lower compression may give you that extra room for error since it has less chance of detonation, but if its not a good tune anyways, its not going to matter.

dthrone

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by MiKeAhOwSkI &raquo;</TD></TR><TR><TD CLASS="quote">I'm looking for people actually running a boosted motor that is at 11.0:1 compression or higher. I've seen a few guys flating around with 11.5:1 but haven't found out too much information.

I'd like to know if you guys have significant trouble running pump gas, or have a lot of problems with knocking. how much boost are you managing to run on pump gas (93)?

Most people seem to love their high compression motors, but everytime I look at the high compression vs low compression turbo threads(because I searched for about 2 hours..), people are not usually speaking from first hand experience.

so if you have at least 11.0:1 CR and are on pump gas, let me know how it drives, what boost you're running etc... ! 11.5:1 turbo stories would be perfect, since that's what I will be at.
</TD></TR></TABLE>

Do it Mike! We live in Wisconsin we have 93 oct!!! haha!

hondaguyef

I am currrently running 11.5:1 JE's in my setup(B18c1 block, B16a head, T04e .80/.70) 10 psi on 93 was good but, anything after that boost pressure amount I couldn't supress the detonation. The car hasn't been on a dyno so I'm not sure at what WHP point it was no longer able to run on pump. I daily drive it on 93 but, it's on a different setup(boost pressure/fuel) for the track.

Phil

_entropy

I tuned a friends setup at 11.2:1 CR. 84mm GSR, JE flat tops, ported GSR head, zero deck. With a GT35R we wern't able to run more than 11 psi on 93 octane or it would knock severely. The motor is now down for a set of 9.4:1 JE's. If you're running the JDM B16 pistons in your motor still, don't even think about boosting it. One bit of detonation and those cast pistons are going to eat dirt.

200cs

I am running a 2000 ITR with Wiseco forged piston at stock CR (I think it is around 10.8 but I may be wrong). T3/T4 9psi, Uberdata. I would not be afraid of using a higher compression engine IF it is tuned right. I am tuning mine on the street and being very conservative with boost until I get it closer to perfect. It will probably take me several months to dial it in. I datalog on the way to and from work and burn chips at both locations. Right now it is probably as good as you get when you pay for a day of dyno tuning but that is not good enough for me.

I know a person who has blown 2 low compression D motors in the last month with a turbo set-up. It was professionally tuned by a local shop but in my opinion it was tuned wrong as it overreved both times and the rev-limiter did not catch it. There were also several things under the hood that just were not right. the work seemed hurried. Anyhow, I am rambling. The morale of the story: there is less margin for error on a high compression motor than a low compression however, if neither is tuned right you will be making all kinds of one-of-a kind engine parts. I hope this helps