turbo lag

sr20_B13 · 07-02-2009, 02:00 AM

I've heard from my pops he's a pro dragracer that if you have a higher compression motor you have less turbo lag on your car, I know it'll give you more horspwer but idk about less turbo lag... Is it true? if anybody knows let me know cause ive searched and i can't find if its true or not...

sergod · 07-02-2009, 02:04 AM

yes its true.

budgetNX · 07-02-2009, 02:36 AM

true to a certain extent.

i dont think it really makes a difference that you can feel.

it has more to do with the turbo, piping, intercooler, restrictions (TB) and your bov

sr20_B13 · 07-02-2009, 12:48 PM

How does it give it less turbo lag

2dr_sentra · 07-02-2009, 04:04 PM

small intercooler piping will give you less lag too.

High compression is just less boost to make same numbers that low compression makes at higher boost. Make sense?

budgetNX · 07-02-2009, 07:24 PM

IMO less boost = more usable power

jmdsentra · 07-02-2009, 07:38 PM

Allot of factory turbo cars come with between 9.5:1 and 10:1 compression now.

With higher compression comes better response and better torque figures however it requires better tuning, as the margin for error is less. That said I believe the perfect compression for a boosted sr20 is 9.5:1

morgans432 · 07-02-2009, 09:41 PM

9.0:1 is ideal IMO

sr20_B13 · 07-02-2009, 11:56 PM

What does IMO stand for... I have stock internals on my highport how many lbs of boost should you guys recommend? and what size of IC piping should you guys recommend also?

chriscar · 07-03-2009, 12:04 AM

What turbo, injectors, maf and exhaust are you running?

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sr20_B13 · 07-03-2009, 12:16 AM

I have 370cc, the garret T25, Cobra MAF, and a 2.5" exhaust to a cherrybomb and to my stock axle back muffler

budgetNX · 07-03-2009, 03:52 AM

i had 2.25" hot side and 2.25-3" cold side piping on a t25 setup with a 10:1 motor. lol no boost lag at all. i made full boost around 2200rpm lol

tear that stock axel back off!!

IMO= in my opinion

sr20_B13 · 07-03-2009, 07:31 AM

thanks bro for the info and IMO was confusing the hell out of me

chriscar · 07-03-2009, 09:26 AM

The lag issue you were worrying about does not exist with a T25, it's got instaboost.

I wouldn't run more than 14psi on that T25. Beyond that it's out of its' efficiency zone and is pretty much just blowing hot air. The limiting factor in your setup is the injectors. Since you don't have an ECU yet, get one programmed for 370cc, 4 bar fuel pressure.

For your IC pipes, go 2" on both sides, or 2" hot, 2.5" cold because one of these days you'll probably want a bigger turbo. And get yourself a 3"exhaust.

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sr20_B13 · 07-03-2009, 03:02 PM

oh yeah i forgot i do have have a tuned ECU forgot to metion that

chriscar · 07-03-2009, 03:15 PM

If you're running 3bar, then limit yourself to 12psi to be safe. You really should get some way to monitor your injector duty cycle. Unless you have a Calum realtime, the easiest way to do it is with a Consult cable like this.
http://www.blazt.biz/products/cable.php

http://www.sr20forum.com/technical-i...hp-output.html

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sr20_B13 · 07-03-2009, 03:34 PM

all i have to do is just buy the cable and software and i plugs in to my OBD input to my laptop? is that correct? I appreciated so much for your help... ALOT...

chriscar · 07-03-2009, 03:43 PM

Yep, that's it. Calumsult is free, and there's a free version of ConZult, but I'd recommend you purchase the software with the cable.

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sr20_B13 · 07-03-2009, 03:55 PM

wich one shoud i but though theres alot of different ones

chriscar · 07-03-2009, 04:03 PM

Here's another option - http://www.ecutalk.com/interface.aspx

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