Swapping From Gtx3576 To Gtx3582

[Skids4kids]

When you say you guys run 20 or more are you referring to midrange boost or boost at peak power?

I didn't think the GTX3576 could blow well into the 20s at higher revs/peak power?

[BenDoCo]

I've still got 19 at about 5200 'ish and then it drops away skiddy

Edit

can't find it atm but I read somewhere (I THINK it was on the garret site) that the ..76 is most efficient at 20 to 22 psi

Edited 26/07/15 10:31 AM by BenDoCo

[747pwr]

I've still got 19 at about 5200 'ish and then it drops away skiddy

Edit

can't find it atm but I read somewhere (I THINK it was on the garret site) that the ..76 is most efficient at 20 to 22 psi

That sounds similiar to how mine is behaving, 18 till about 5000 then drops. Its the second one the workshop I have used has done with gtx3576 - it cant push over 500rwhp with near identical parts spec but manual - our dyno does read low, When "big cars" from other workshops run on it they regulary show lower power figures- so I wouldnt be suprised if it is making more than 470rwhp but we cannot get it to make any more boost than 18psi, tried asking for 30psi, tried different actuator tensions, ran it with the gate closed, ran it on just the 4inch dump pipe, its got a plaz 4inch race intake so left that in place. Any suggestions for things to try would be great but I think we have covered everything

[PAH]

Guys.

Not sure how much boost I am running with my GTX3576 but it's making just under 360kw at the wheels with a new Zorst and PW stepped cooler. Comparing the dyno charts (factory turbo to GTX3576) I've lost a bit of mid range torque with the GTX3576 and I guess that's to be expected. I think that the GTX3576 is a good turbo for street use. I doubt that I'd fit a GTX3582 to a street car. I remember reading a post that said that the GTX3576 smokes the GTX3582 on the track too. By the time the GTX3582 comes on boost, he's at the next apex. It was that post that pushed me towards the GTX3576.

PAH

[747pwr]

PAH, thanks for posting- can I ask what outcome you asked your tuner for ? Did you want 360ish or asked them to tune it for everything it was capable of ?

[barnz]

PAH I really don't see how you could have lost midrange over the standard 76...what's the tune like? Have you got a sheet that shows the boost curve? Sorry if you have already posted it. The little gtx in hard and fast should basically be...well a useless tyre fryer lol. If set up right from what other peeps who have one have said its better everywhere?

[bjc]

I still find it strange that you can't get over 18psi regardless in the mid rpm range? If you are then I would say ok but if you aren't then I believe there is a bigger problem as holding the gate shut is boost heaven (with potential grenade status) and should easily see 20+ unless the ported housing is rooted?

[747pwr]

I agree that the 76 is better all over the standard turbo, it just lacks top end for me which is why im thinking of simply swapping the cores and hoping the gtx3582 produces the tyre carnage I'm after but it will enter gearbox and motor danger zone for sure.

[747pwr]

I still find it strange that you can't get over 18psi regardless in the mid rpm range? If you are then I would say ok but if you aren't then I believe there is a bigger problem as holding the gate shut is boost heaven (with potential grenade status) and should easily see 20+ unless the ported housing is rooted?

When I said we held the gate shut that was only on the dyno for testing purposes, honestly we have tried different pressure springs in the turbosmart actuator, exhaust dropped, disconnected signal line to actuator, different actuator, commanding maxiumum possible boost, nothing can make it produce anything more than 18psi or 16psi at the peak. The housing was used on another vehicle and they actually had trouble keeping the boost from going too high until the porting that is still current, was done.

[bjc]

Not knocking you mate as I did this (steel wired the wastegate shut) while testing a friends FG on the street as it simply wasn't coming onto boost until 4500rpm with it even wired shut which meant to me that the wastegate porting was fcked which it was!

So you are saying that you couldn't make over 20psi with your combo, then put the turbo on a different car and had no low boost problems to which they fitted a ported housing to the second car then boost was under control and then that complete turbo with new ported housing was fitted back to your car?

If that all is a yes then the problem lies with your car somewhere and not the turbo... Is be checking for boost leaks from turbo all the way to the intake manifold to head and also exhaust housing leaks!