lbs of boost on stock T-25?

[99EclipseGSX]

I was just wondering what is the max psi that i should run on a stock
T-25?
Thanks
Bryan

 

[2gTurboS]

It depends on your mods but 16psi is generally the norm. Corey

 

[Vinnie]

You can run 18psi with the stock fuel pump, more than that and you will get fuel cut.

But like 2gTurboS said most people run 15-16 psi.

 

[Violater101]

If I here this asked one more time , I think I am going to cry. This should be in the "Newbie" forum and noone can tell you what is safe. I don't mind helping people, but if I had a dollar for everytime I have seen this question asked on this board. They can only tell you what they think will be safe. All far's are different, but the rule of thumb on a t-2slow is anything after 15lbs of boost is just hot air and not worth the extra 5-10 you may get out of it. You will be making the turbo work alot harder and it will die alot faster than it would normally.

 

[99EclipseGSX]

Well i didnt think a million people asked this question so sorry for asking. Anyways, thanks for the help guys.

 

[Violater101]

I didn't mean to come off as rude so don't take it the wrong way. As I said in my post, I wouldnt run more than 15lbs unless you plan on getting another turbo in the near future Happy boosting

 

[99EclipseGSX]

Allright it's cool dude. i didnt mean to come off the wrong way either, i just didnt know it was a "common" question my bad. it's just i am new to the DSM community and do know very much about them. But thanks for lettin me know not to run more than 15 lbs.

Laterz
Bryan

 

[larryd]

i love throwing this in after people say not to run more then 15psi

http://www.newcelica.org/larryd/dyno/02-01-02-dyno_comparison.jpg

dyno 1 was 14lbs
dyno 2 was 18lbs
dyno 3 was 22lbs

 

[Violater101]

Well, I never said you wont make more power, cause you will. A friend picked up about 10 hp on 18psi or so, but your turbo isnt that efficient up there and its only hot air. If you want to kill your turbo, go on ahead I would just disagree about running more than 15lbs of boost

 

[greyforestgst]

Originally posted by larryd
i love throwing this in after people say not to run more then 15psi

You must be logged in to view this image or video.

dyno 1 was 14lbs
dyno 2 was 18lbs
dyno 3 was 22lbs

pictures say a thousand words, don't they?

18psi looks pretty healthy on that chart. only a gain of 10 or so max horsepower over 14, but the power curve jumps up a lot higher 3 to 5 grand due to a 50 ft lb torque increasement down low.
and again, like most say, your max power is always 4 to 6 thousand rpms. now im not sure if 18 psi is very healthy for the turbo itself, but the engine can take 24 psi stock, so there's no worries there. the fuel pump may have a little trouble around 18, so i would say that 17psi is a decent figure for max feasable boost on a t25. of course you can go higher, but without significant gains and with shorter life on the turbo itself.

 

[Faded]

I thought I read somewhere that running +20 psi on a stock bottom end is bad? Anyone confirm / deny ?

 

[larryd]

i dont see why.. its not the amoutn of boost that has any effect on the bottom end, its the power your putting down and the T2small is gonna be nowhere near enough power to be at the limits of the stock bottom end.

 

[Faded]

Maybe it was fuel I was thinking of. Here in Cali we only have 91 octane so it kinda puts a damper on high boost

 

[larryd]

well yeah i can see that.. maybe the car would be knocking becuase of the lack of octane in the fuel. I know I cant run over 20lbs with any turbo ive had with 93 octane.

 

[Faded]

Do you have a Knock LED installed or do you not monitor it? I tune with the standard EGT / O2 / Timing but I have no idea about my knock. I do get a stupid 0325 (or something ) knock sensor msg on my pocketlogger that I should look into someday.

 

[larryd]

i have dsmlink which shows my knock now.. back when I had the T25 I didnt pay much attention to anything other then EGTs and o2 values.

 

[Faded]

In your opinion is it worth throwing in a Knock Sensor LED? I'm not sure how good a blinking light would be, but maybe there are Knock Sensor mods that hook up to a digital readout or something?

 

[larryd]

i dont know, since i dont have it

 

[Kevin Jewer]

There is a reason the power increase is mostly in the low end as boost is raised on the T25. Kncok goes through the roof at higher rpm and timing is pulled, to almost the same HP level. I datalogged every possible boost level and ran them all at the track a dozen times a week for a year. 16 psi was fastest and safest on my setup. On race gas however, 20-22 psi dropping to the usuall 15 psi after 5500 gave me a .5 second gain with no fuel control. I ran a 13.7 at 99, but when I switched to higher octane I got slower since I had no fuel control. Shortly after the turbo died Stick to 16ish on the street, and datalog if at all possible to make sure that is the right number for your individual setup...