Manny86

im running a t3t4 50 trim 48 ar on my vitara build i want to know how many lbs i can run on pump gas?

Schister66

Your tuner will be better able to determine that....it depends on the efficiency of the setup, the temp and grade of fuel

Manny86

i just want to get the most i can running pump gas

boosstboy

what's your compression?

Manny86

what ever the vitara pistons are i think its 8.5.1 or something like that

boosstboy

i would say around 12psi, stock block?

nihad

iTrader: (2)

if your compression is high like 11-12 :1 then u will have to run a high octane gas and if it what yours is
u could get away by using 91+ and get good gas mileage unlike 89octane. It burns faster.

Manny86

no the block has eagle rods vitara pistons endyne oil pump stock head with arp head studs

boosstboy

i've seen some my friends run their soch's on 10-12psi with stock compression. it's all in the tune, that will determine if it blows at 5 or 15psi or last 1 week or 1 year. i would say for that compression with that setup 15psi wouldn't be out of the question.

Manny86

what would i be looking at for hp ?

quicksilver1689

psi is a function of the engine/turbo setup and how it responds/efficiency. 350whp is about the limit IMO for pump gas sohc's. For a daily driver i would stop at around 300whp

Manny86

its going to be a daily driver but i want to have good numbers at the track im not going to run full boost on the street . how many lbs do you think it will take me to get 350hp out of my setup on pump gas?

SOHC_MShue

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by boosstboy &raquo;</TD></TR><TR><TD CLASS="quote">i've seen some my friends run their soch's on 10-12psi with stock compression. it's all in the tune, that will determine if it blows at 5 or 15psi or last 1 week or 1 year. i would say for that compression with that setup 15psi wouldn't be out of the question.</TD></TR></TABLE>
i've been running 15psi for a long time now on stock compression

RCautoworks

I think the question should be more what my block can handle, not whats the limit on pump gas.

SOHC_MShue

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RCautoworks &raquo;</TD></TR><TR><TD CLASS="quote">I think the question should be more what my block can handle, not whats the limit on pump gas. </TD></TR></TABLE>
why? He has a vitara setup. The block can handle way more than what it can run on pump gas without detonating. If he wants to always run pump gas then his question makes sense.

RCautoworks

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SOHC_MShue &raquo;</TD></TR><TR><TD CLASS="quote">
why? He has a vitara setup. The block can handle way more than what it can run on pump gas without detonating. If he wants to always run pump gas then his question makes sense. </TD></TR></TABLE>

Because people are telling him 12psi is safe... you can run a lot more on pump gas then that. The guy is basing his goals on what psi he can run safely on pump gas. The question should be what amount of horse power can I push on my block/setup safely.

It really is going to depend on who is tuning it, but you can definitely run a lot more then 12psi on pump gas.


<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Manny86 &raquo;</TD></TR><TR><TD CLASS="quote">i just want to get the most i can running pump gas </TD></TR></TABLE>

Who knows what your tuner is capable of , if your going to base your setup on that, drive to the tuner, tell him to turn the boost up until it starts knocking and thats the limit.


Modified by RCautoworks at 1:12 AM 12/17/2007

RCautoworks

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Schister66 &raquo;</TD></TR><TR><TD CLASS="quote">Your tuner will be better able to determine that....it depends on the efficiency of the setup, the temp and grade of fuel</TD></TR></TABLE>

Yep pretty much

ralph11sec

i did 16psi on my vitara build before with gt30r. around 320whp. 93octane.

check sig.

d16z6Tcrx

i was tuned at 15lbs on an sc61. i put down 330whp on pump. most tuners will tell you that is not the psi that sets the limit its the power you put down. jeff evans said a long time ago that he stops tuning pump gas on a sohc around 340 350whp. anything more that is getting dangerous when it comes to setting ignition timing. hope that helps

SovXietday

Lots of guys in the SOHC thread are pushing 15-19psi on Vitara blocks with that turbo making low 300s. However I think the .48AR is going to hurt your numbers, upgrade to the .63.

All in all it depends what octane your pump gas is and who tunes your car.

roachsboosted16

i kno some one that runs 20 on 91oct for about 3 years now about 40000 miles.

d16z6Tcrx

its prolly a really small turbo and isnt putting down a whole lot of power

HiProfile

93 octane, given a good setup, starts having issues at 18-20:1 static compression. Now thats static, not dynamic. Overlap and reversion affects static compression, which gives you dynamic. When you max pump gas, you either get pre-ignition/detonation, or have to pull timing so much that EGT's get very high for very few WHP gains.

I've seen a local tuning shop do a bunch of 400whp ~9:1 b18's on 93 octane, and they were doing ~21psi. I think one only gained 15whp with another 5psi. That same shop also did a built D16Y8 with a 57trim on 93 pump and got ~350whp at 18psi - and they said it still had more left in it.

btw there's no evidence to support that 100 octane burns slower than 87, at least not enough to affect tuning strategies. It is dumb to run 100 octane in a stock NA setup made for 87, as its just wasting money.

Schister66

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by HiProfile &raquo;</TD></TR><TR><TD CLASS="quote"> When you max pump gas, you either get pre-ignition/detonation, or have to pull timing so much that EGT's get very high for very few WHP gains.</TD></TR></TABLE>

x2

Let your tuner, who has more experience, decide when you've maxxed out on pump. You CAN run more boost, but like HiProfile said, you're going to end up pulling so much timing in order to make it not pop, that you're not going to gain a lot of power...

Manny86

im going to have Chris Harris from xenocron.com tune my car. i just want to have a car that makes atleast 350whp with pump gas.