1bar boost on Stock CA turbo....how safe

RBSX · Post by **RBSX** » Fri May 23, 2008 8:56 am

Hey guys any one running the stock T2.5 on 1bar reliabilly

I did the DE cam upgrade and im now gone slowwer that a Golf GTI.....WHY..........GARY....got a hiding last night

So is anyone running the stock turbo on 1 bar,,,, whats it like

Sokar · Post by **Sokar** » Fri May 23, 2008 9:06 am

I'd say not a good idea...

1 Bar is waaaay past a stock T25's efficiency range, you will be blowing more pressure, but at a much higher temp.

If you did a dyno at 0.5 bar for example you might get 130kw, at 0.8 bar you might get 150kw, but at 1 bar you make 156kw, that small jump in kw shows the turbo isnt coping, its past its range and you're just pushing a whole lot of hot air...

Gary57 · Post by **Gary57** » Fri May 23, 2008 9:28 am

Donny whats happened, what cam was that?? Are you sure it was a DE cam?? Even if it was a DET cam it should go the same as it did and I doubt it is that lean that it is slower.

Gary57 · Post by **Gary57** » Fri May 23, 2008 9:37 am

Donny are you sure it wasnt a Debben Standard G5GTi??

rat · Post by **rat** » Fri May 23, 2008 9:47 am

Gary57 wrote:Donny are you sure it wasnt a Debben Standard G5GTi??

what is that?

Drop springs, mags, zorst, and nos bottle?

Gary57 · Post by **Gary57** » Fri May 23, 2008 9:55 am

No forged internals, T66 turbo, nos.

Then they claim it is STD.

Doctor G · Post by **Doctor G** » Fri May 23, 2008 10:02 am

yeah streetrace is hardly a way to measure your car's performance.

Before you do any drastic mods just dyno run the car and see what's up.

Your stock T25 should boost close to 0.7bar and hold between 0.5 and 0.6 bar.

Draco · Post by **Draco** » Fri May 23, 2008 10:07 am

On the stock turbo I would say 0.8 is the maximum you will be able to go reliebly, it will give you around 4-8 rw kw ... at the most unless the car is retuned properly, then you might get around 10....with a unithip and a zorst you should get around 15-25 rwkw at the most depending on the monkey behind the tuning

Pinkfluffybunnys · Post by **Pinkfluffybunnys** » Fri May 23, 2008 10:10 am

From my Experiance the stock T25 is already stresed at stock boost levels.

Draco · Post by **Draco** » Fri May 23, 2008 10:19 am

That might be your experience....mine was at 1 bar for around 7 months before I reconned it, was not really needed but I wanted to upgrade the compressor wheel.

Also different situations will give different results.....those days I idled the car at least for 3-5 min. before driving and the same before I switched off the car....I am sure that helped and also I did not push it to full boost every time I drived....

Pinkfluffybunnys · Post by **Pinkfluffybunnys** » Fri May 23, 2008 10:52 am

Also different situations will give different results.....those days I idled the car at least for 3-5 min. before driving and the same before I switched off the car....I am sure that helped and also I did not push it to full boost every time I drived....

LOL, that wont help much with the extremely heated air charge steaming into you intake

Fact is the Turbo is beyond it efficiency range and really If you want to push you stock hairdryer to that point then that’s you decision, The point of the post is it “Safe“and “Reliably” the short answer is NO it never will be also it will start choking the motor as the boost pressure increase because on the small exhaust housing causing “Spikes” and massive amount of “shaft over spin”

It will also overload the stock cooler, but I’m sure RBSX has water cooling or a FMIC to combat this …

Draco · Post by **Draco** » Fri May 23, 2008 10:57 am

Thanks for your opinion...I gave mine...great

RBSX · Post by **RBSX** » Fri May 23, 2008 2:38 pm

Thanks guys, Some good stuff there.

nah i raced this car before, its stock stock...not durban stock

Im going to do it this way, Install chip dyno, Check power
Then up the boost to 1 bar, check power if its more than 15rwkw ill keep it on one bar, if not ill drop back to 0.8

Im not concerned about blowing the turbo, i dont wanna blow the engine though, will doing this blow my engine , I heard of impellers shattering and going into the engine and busting up pistons......

Draco · Post by **Draco** » Fri May 23, 2008 2:55 pm

I would suggest that you add an aftermarket intercooler or a straight pipe from turbo to inlet with water/meth or an intercooler with water/meth to cool down the charge, your engine should be fine if the tuner sets it right, it must not detonate/ping.

If you add water/meth you should get more because of increased timing capabilities, then you can bring down boost to save your turbojernals from being used faster.

The only way this turbo wheel will shatter is if something hard gets into it and pushes it into the intake, as for the compressor wheel shattering for no reason....not easely.

A suggestion, if you really want to boost 1 bar, you will have to recon the turbo at least once or twice a year, save that and rather ad a turbo that is able to boost 1 bar with less stress. Turbo life will increase together with reducing other dangers.

You must always remember, upgrading a engine always puts it under stress, puch it now and then fine, drive like a hooligan all the time and chances are something will go wrong at some stage, if your gonna mod, always remember to do it the right way, it will save you alot later.

RBSX · Post by **RBSX** » Fri May 23, 2008 3:39 pm

Thanks Draco...thanks some good stuff there, Ive got a Bigger FMIC
Ill consider the Water meth injection