Supra Forums banner
1 - 20 of 22 Posts

·
My name's Scruffy.
Joined
·
1,566 Posts
Discussion Starter · #1 ·
who here has ran what amount of boost on the stock turbo without it going out....so far for the past 2 weeks, my car has been running 1.11 bar (16.1psi) and ive had NO problems what-so-ever. stock HG, etc....

what have you ran on ur stock turbo?

and what is the highest for any turbo in the 7m-gte motor?
 

·
Banned
Joined
·
676 Posts
What kind of fuel system upgrades do you have? what do you use to tune?

ive heard that 15-16 psi is about the max for the stock turbo,anything over is said to be out of the effienciency range. however ive heard of upgraded ct's running up to 22+psi. I would think anything over about 12psi on a daily basis would be about max if you wanted it to be reliable, depending on how many miles it has on it.
 

·
My name's Scruffy.
Joined
·
1,566 Posts
Discussion Starter · #3 ·
yea i know about the upgraded and whatnot...running 22psi.....
all i have is lexus AFM, walbro 255lph and thats it for fuel, no tuning, downpipe, exhaust, intake, intercooler with hardpipes..

i know people will say this is stupid, but ive been lucky....lol...so far no problems like i said...in fact my car has been running ungodly rich, even boosting..dunno why...

what i meant by a different turbo isnt the ct-26 upgrade..im talking a whole different make of turbo, i.e. turbonetics, sp, etc....
 

·
Premium Member
Joined
·
4,409 Posts
2 years at 11-15 psi and this year a few times at 19psi, never for extending periods of time, if im driving hard for a long time i set it to 12...

20+ will blow it fast like under a month...

Ang
 

·
Registered
Joined
·
927 Posts
2 months at 12-15psi was perfect....

1 month at 18-20psi hold, + a few(accidental) 24 and 29psi spikes, turbo was toast....the exhaust side wheel almost falls off when you tap it
needless to say I swapped another turbo on :D
 

·
Registered
Joined
·
372 Posts
So Viperloc, you've been running 16psi on a stock headgasket? I just replaced mine and used ARP bolts torqued to 80lb/ft, I guess I can confidently start running a little higher than 9psi (with the appropriate fuel mods of course:))
 

·
Registered
Joined
·
927 Posts
You don't need fuel mods to do that dude :p

Mostly Thumbs said:
So Viperloc, you've been running 16psi on a stock headgasket? I just replaced mine and used ARP bolts torqued to 80lb/ft, I guess I can confidently start running a little higher than 9psi (with the appropriate fuel mods of course:))
 

·
Registered
Joined
·
372 Posts
The impression I got was that the stock headgasket was big POS and couldn't hold much more than stock boost levels.....mc_h were you/are you running a stock HG when you hit 18-20psi?
 

·
Registered
Joined
·
927 Posts
No I have a MHG...When I ran 18-20psi I just had intake, exhaust, lex afm & at some point during that time, the safc

I was just saying though, you dont need more fuel to up the boost past 9psi...You wont hit fuel cut till 12-15psi depending on the car and the weather anyways :)
 

·
ƒ=1/2π(√k/m)
Joined
·
10,160 Posts
Stock HGs are structurally fine.... The torque setting wasn't


If you have proper hardware arp bolts, you should be alright

But a MHG is really what you want
 

·
Certified Supra Nut :P
Joined
·
2,001 Posts
Stock headgasket should take a good 300hp if it's been torqued down properly (I dunno about 80lbs though, it is possable to overtorque the head too).

The Stock CT-26 falls drasticaly out of it's efficiency range after 12-14 PSI (really it's anyones guess, but temp readings I have done put it about there). 60-1 Upgraded CT can run 15-16 before it gets inefficient.

That being said, you can get more power out of a turbo by running it out of it's effieciney range, it just becomes a factor of diminishing returns, and too far can cause drasitc damange (to turbo and engine). If you do plan to run higher than the efficient boost level for your turbo, I HIGHLY recommend an upgraded intercooler. You'll be generating a lot of excess heat that needs to be dealt with, so don't forget to keep that in mind when you stick that extra washer in there :D
 

·
boost freak
Joined
·
10,042 Posts
word. stock HG is fine....

FWIW- i blew my stock HG @ 17psi on the stock turbo......anything past 13ish psi = lots of heat.....be careful kidz.....
 

·
Registered
Joined
·
372 Posts
Cool...Thanks for the info guys. My turbo is on it's way out, there are a few chips in the compressor blade, compliments of the previous owners silicon fix on the accordian tube. I was thinking of the bolt on upgrade from Suprasport. That should keep the heat down at 13-16psi, correct?
 

·
Registered
Joined
·
927 Posts
I really wouldn't bother getting an upgraded CT until you have the supporting mods. Especially a better cooling system - Whether it be water injection or a bigger front mount w/ hardpipes.
I know you're relatively local to where I am but I'm not sure who you are, otherwise I would have an idea of your mods :)

Mostly Thumbs said:
Cool...Thanks for the info guys. My turbo is on it's way out, there are a few chips in the compressor blade, compliments of the previous owners silicon fix on the accordian tube. I was thinking of the bolt on upgrade from Suprasport. That should keep the heat down at 13-16psi, correct?
 

·
ƒ=1/2π(√k/m)
Joined
·
10,160 Posts
Well... You can have the upgraded ct, and not boost hard. And functionally speaking the turbo will still out perform the stocker.


Just cause you have it, doesn't mean you can go willy nilly with the boost! **shurg**
 

·
Registered
Joined
·
372 Posts
I just figured.....since it's broke (ish) why not upgrade for the future.
Mc_h...my current mods are, RT downpipe and cat, intake, PVC hardpipes, piece-of-shit cat back, Bosch blow-off valve and soon a turbo elbow.
As for cooling, in the summer I run 80/20 water/coolant with water wetter (60/40 in the winter) and the rad is nearly new. The previous owner replaced it 1 yr before I bought the car. I got my hands on another stock IC and after cleaning both, am going to try running dual ICs (JBLmk3 style).
 

·
Registered
Joined
·
927 Posts
Mostly Thumbs....

Dual IC is a big hassle...And you also have to remember that our stock IC's really do suck for higher boost....by 15psi you'll be having like 5psi in pressure drop. John Lubsford may have made 450rwhp on dual IC w/ a 60-1 ct but realistically speaking, it wont happen in many cases...Basically you just cant get an upgraded CT and raise the boost up on it without supporting mods...Get a lex afm & crush the stock fpr to say, 43psi or so....But you'll need an SAFC to adjust it
or just go lex afm w/ an afpr which is probably the best route really...Either way, upgrading the ct with the same airflow isn't exactly optimal - Which is why you should go lex afm or wait till that MAF conversion thing comes out....You can still do it, just dont expect amazing results until you open up airflow and give it some fuel :)
 
1 - 20 of 22 Posts
Top