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Stock Ceramic Turbo And Boost Surge/spike

reNEGaDe88

By reNEGaDe88,
in Engines & Forced Induction

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reNEGaDe88 Proficient

reNEGaDe88

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Hey guys.

I have read up on how much boost a R33 stock RB25 turbo can handle. As I have one.

I had my car tuned at 13psi making a generious 291 rwhp. I have a AEM Electronic boost controller.

So I run it on 12 psi seeing as I gather that 14+ the turbo is likely to fail.

So I was driving my car this morning at 9am. I let it idle warm to 70 deg C and then took it for a drive. Air was super cold from yesterdays rain.

When I was boosting the car was reading 15 and 16 psi a few times and then as I continued to drive for 10 minutes it would level out at 12psi again.

So I am wondering if my turbo surges or spikes to 15-18psi every so often on cold mornings or nights, up hills or in high gear. Will the turbo explode soon?

Cos I don't want to feed my turbo some compressor wheel peices.

Thanks in advance

Berny

reNEGaDe88 Proficient

reNEGaDe88

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its not ideal. Id get it sorted out.

And your turbo wont be fed a compressor wheel. It is the compressor wheel :P Maybe you mean engine haha.

hahaha yeh, typo. Meant, I don't want to feed my engine compressor wheel pieces.

Ultimategtr Proficient

Ultimategtr

Posted
Posted

I used to get that on my stock turbo.. MS-IBC boost controller set to 7/10psi.

On low boost on a cold night/morning it would creep up to around 9psi initially but settled to 7psi spot on..

on high boost it would initially creep to 13psi but it would settle down to 9-10psi rock solid once the ebc discovered it was creeping.

The other thing i used to do was decrease the gain a wee bit to help.

If your turbo creeps to 14psi and STAYS there, then possibly you havent fine tuned it and thus would need to decrease the GAIN/Start boost.

You def dont want to run 15-18psi otherwise:

1) Turbo's exh wheel WILL break

2) You will hit mass over-run and the ecu will do weird shit to save the engine

reNEGaDe88 Proficient

reNEGaDe88

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Oh. The boost controller must be allowing the wastegate to open later to run higher boost. But when the air is cold/dense and the intercooler has not soaked up heat, then the boost creeps. The EBC then realises it and settles it back down to correct setting.

How do I decrease the gain?

Nah for like 5 or so full gear runs the boost was at 16ish. Then it got better and sat at 12psi.

Turbo's explode purely due to hoop stress if they are ceramic, not because of heat or dirty oil. Just because they are spinning too fast and to much energy.

So if my ecu stops the car from leaning out. The turbo can still explode cos the ECU won't stop the turbo spinning too fast

reNEGaDe88 Proficient

reNEGaDe88

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Any other input into this?

I wanna know how serious it is running 15-18 psi when engine is cool and if turbo will explode. Or not.

Otherwise I will definitely get a 2535 or 2835 or GTRS really soon.

Dammit, so much money :D

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