how high of compression can you have to safely run a turbo setup.

this is why i asked, i had a local shop rebuild my engine and here is a list of what the done:

bored (i believe it to be 1.95)
honed
eagle crank
aries 12:1 pistons
stock rods
port and polish
5-angle valve job
converted chambers

the only thing that i'm not happy with is that they talked me into getting those pistons and now i have a high compression non-vtec b18, but i want to work with what i've got and i want to turbo. is this possible?

if it is possible, it will be low boost and small turbo.

<shane>

 

You can boost at 12:1 just not very much.

If you want to boost higher, you can run it on methanol or alcohol injection.

But you will have to run high octane fuel all the time. Like 100+

 

When you start raising compression, you start raising temperatures and create hotspots in the combustion chamber.

In order to boost more, you will have to introduce more cooling or lower the compression.

Methanol or alcohol/water injection accomplishes this by drastically cooling the chamber and helping to eliminate pre-ignition. You would also need to run a higher octane fuel as well.

Start planning on alcohol/water injection and an air-to-water intercooler at the least if you want to do this right. IMO.

 

Or just pull a LOT of timing.

Either way, it's not going to be an easy project.

I would suggest some infinitude close ratio gears.

80% rpm drop FTW

just ask ATS/Infinitude/Quaife/Spoon what the ideal rpm drop is.

79-82% from 2nd (1st to 2nd is usually like 70%)

 

Some food for thought.


If you want to find out what your CR will be under boost, here is the formula. Keep in mind, your altitude WILL play a role in your final static CR.

Final Compression Ratio (FCR) = [ (Boost÷14.7) + 1 ] x CR

Boost = Maximum blower boost
14.7 = psi at sea level
CR = engine compression ratio

Corrected Compression Ratio = FCR - [ (altitude÷1000) x 0.2 ]


So, if you boost 7 psi in an engine with a CR of 12:1 at, say an altitude of 4000 feet, you will end up with a static CR of 17.7:1. Good luck tuning that on pump gas!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SuzukaBlueAP2 &raquo;</TD></TR><TR><TD CLASS="quote">Some food for thought.


If you want to find out what your CR will be under boost, here is the formula. Keep in mind, your altitude WILL play a role in your final static CR.

Final Compression Ratio (FCR) = [ (Boost÷14.7) + 1 ] x CR

Boost = Maximum blower boost
14.7 = psi at sea level
CR = engine compression ratio

Corrected Compression Ratio = FCR - [ (altitude÷1000) x 0.2 ]


So, if you boost 7 psi in an engine with a CR of 12:1 at, say an altitude of 4000 feet, you will end up with a static CR of 17.7:1. Good luck tuning that on pump gas! </TD></TR></TABLE>

interesting.

 

by the way, i'm already running 4 gallons of 110 and the rest 93, as well as an aftermarket fuel filter, regulator, and rail.

 

ok, with everything i got now including hondata s200 and all the fuel components.

what kind of psi should i push and what other precautions should i take. i was thinking 3 psi daily driven, but have a manual boost controller (more like a switch, from 3 psi to a higher psi).

p.s. thanks for all your help guys, i knew i could count on H-T.