Question about boost/octane (evo 3 16g)

[1998gstspyder]

So I got an Evo 3 16g on my Gst Spyder. I got 660cc injectors, 190lph fuel pump, etc.

1. What is the highest PSI i can run on 91 octane?

2. What is the highest PSI I can on this turbo? And at the PSI, what octane should I use.

 

[crazy_skier]

if you have a logger i would continue to turn up the boost and fuel until you start to see knock... and then back it off 1 or 2 psi. But anywhere from 17-20 can usually be seen (sometimes more or less, all cars are different). Go out, log away and have some fun. if you need help post a log or two if you can

 

[gsxeclipse97]

get a logger and tune make sure your not getting any knock and pulling timing. all cars are different so there is not great anwser that we will be able to give you so that is your best bet there.

 

[marq95gst]

From what I've encountered with 91 octane, and 660s is that about 19-20 psi works best. You can go 21-22, but 19-20psi for safety..until you can get a logger and check out knock, etc...

 

[force it in]

I run 25 psi daily on 91 octane with a 50/50 water meth injection. Less than 3 counts of knock. With the water injection off I see around 14 counts of knock.

 

[1998gstspyder]

here are my mods btw, dont know if its profile or not.

dejon tool intake, cone air filter, mbc (soon to be dual setting ebc), fmic, 660cc injectors, 190lph fuel pump (so cant get 255), safc2, evo3 o2 ported housing, 2g intake manifold ported, apexi 3 inch turboback (no cats), act 2100/12 lbs flywheel. i got egt/boost guage/a/f guage.

the reason why im asking this question is because I want to go get it dyno tuned. I want to tell the guy to tune my car at the highest psi (or cfm) with like 100 octane, or maybe 110. this would be my track/race setup only.

i also want the guy to tune my car at the higest psi possible with 91 octane, this would be my high setting for street driving.

lastly, i want the guy to tune my car at a lower psi that doesnt spin my 1st or 2nd gear (fwd), so that can be my low setting for street driving

so from reading all your posts, i guess I can tell the guy to keep raising the boost until i see knock, but what octane should i have in there when im having it dynoed?

also, how would he tune for 91, when i have the higher octane in there? would i have to remove it and have it tuned again?

 

[crazy_skier]

I would tune for 91 first, and go to him with low gas. Then I would add race gas and get it tuned, and then when you are at the track you will be a little conservative. Or you could always add toluene and have cheap race gas

 

[Eastwood95]

If you just buy a wideband and logger (which would probably be cheaper than paying a shop to tune you once anyways) and learn how to tune it yourself, you can tune it whenever you want on the fly for whatever gas/psi you are running. Its not rocket science man, you'll save money, learn something new, and get to know your car better.

A wideband is $280
http://www.extremepsi.com/store/customer/home.php?cat=746

A logger is $150
http://www.pocketlogger.com/index.php?pid=pldsm
http://www.obdloggers.com/mitsubishi.htm

 

[dsm-onster]

here are my mods btw, dont know if its profile or not.

dejon tool intake, cone air filter, mbc (soon to be dual setting ebc), fmic, 660cc injectors, 190lph fuel pump (so cant get 255), safc2, evo3 o2 ported housing, 2g intake manifold ported, apexi 3 inch turboback (no cats), act 2100/12 lbs flywheel. i got ebc/boost guage/a/f guage.

the reason why im asking this question is because I want to go get it dyno tuned. I want to tell the guy to tune my car at the highest psi (or cfm) with like 100 octane, or maybe 110. this would be my track/race setup only.

i also want the guy to tune my car at the higest psi possible with 91 octane, this would be my high setting for street driving.

He'll do both if he's a good guy and wants business. Also, he'll tune it for what you can get out of it and ask you whether or not you're going to drive this around daily or if you're concerned about reliability. Then he'll back of the tune based on your answer.

lastly, i want the guy to tune my car at a lower psi that doesnt spin my 1st or 2nd gear (fwd), so that can be my low setting for street driving

As your launching skill increases, you're desired hp in the lower gears will go up. I wouldn't tune the lower gears w/ the lower psi. I would tune for MBT and best a/f ratio at the highest boost you want to run at the track, then lower the boost in 1st and 2nd. There's no real way to tune just a particular gear w/ an safc anyway.

In fact, I'd not run the lower boost at all in 1st and 2nd. Your throttle can modulate the hp delivered to the ground quite well. As you get better, you'll notice that your foot is traveling farther to the floor.

also, how would he tune for 91, when i have the higher octane in there? would i have to remove it and have it tuned again?

You can remember all the settigns for the SAFC as he tunes w/ each octane. Or you can tune for the best of race gas and alter just the boost for pump gas. Or, the other way around.

 

[Eastwood95]

I still say learn how to do it yourself, do you always want to rely on someone else to tune your car and not know what they are doing?

http://www.dsmtuners.com/forums/showthread.php?t=103469

http://www.dsmtuners.com/forums/showthread.php?t=58403

http://www.innovatemotorsports.com/resources/lm101.php

 

[Nors]

Can someone pm me the software to log? My car came with a logger and cable but no software.

 

[1998gstspyder]

I still say learn how to do it yourself, do you always want to rely on someone else to tune your car and not know what they are doing?

http://www.dsmtuners.com/forums/showthread.php?t=103469

http://www.dsmtuners.com/forums/showthread.php?t=58403

http://www.innovatemotorsports.com/resources/lm101.php

whats funny is i actually got a logger/software and cable, i also have a safc2, do i still need wideband? i just need someone to teach me, im scared i might #### up my largest investment by doing something wrong.

 

[Nors]

Yes wideband will be needed. Especially if you are new to tuning. The narrowband is nowhere near accurate enough.