Since fitting my new clutch and lighten flywheel I have massive boost creep.

The car is running a hybrid turbo with a full 3" exhaust system, I know it's the exhaust thats causeing the problem and I'm getting a section of 21/2 " pipe fitted to hopefully bring the boost back under control just now but was wondering if it would be practical to modify the turbo. E.G

Was thinking along the lines of getting the internal waste gate welded up and fitting and exsternal waste gate which should solve the problem of the boost creep.

Was wondering if you think this is a do'able job or if there is some other way of solving the problem.

Cheers

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287 bhp / 254 ft/lb.
It's Orange and I love it

Fitting a restrictor plate in the exhaust might be a lot easier and cheaper - I think Mike did this as a temporary fix.

Porting out the wastegate should help, but isn't gauranteed.

I run a 3" system and have not had the same problems as other owners with the stock turbo, but maybe I'm "special"

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Kris
95 ST205 - slept for 10 years, now waking up...
Avensis
http://www.gtfours.co.uk
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Turbocharging - the replacement for displacement

When i had a 21/2" down pipe it was alright, I then fitted a 3" down pipe and started to get boost creep but it wasn't to bad from 10 psi to about 13psi.

But have know fitted a lighten flywheel and the car comes on boost a lot quicker and hits fuel cut very eaisly if i don't keep one eye one the boost gauge.

The way my exhaust is built it is not a big job to put a section of 21/2" pipe where the flexi is. but I was wondering if members thought it was possible to modify the turbo as i suggested or if there where any other suggestions.

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287 bhp / 254 ft/lb.
It's Orange and I love it

It is possible to port the wastegate but it is not guaranteed

I think Sirius still has some creep despite a hybrid with a ported WG

You could also wels up the wastegate and fit an external one

However, fitting it will cause other issues:-
Assuming you use a takeoff adapter which bolts between the ex mani and the turbo, you will lower the turbo by 1" (say).
This will mean your DP no longer fits
Or your turbo -> IC hoses
Or the stock oil/water lines
Or turbo heatshield

See where this is heading?
It can be done but with the amount of effort involved you'd probably wish you had plumped for a whole new turbo setup

You could talk to turbo technics about one of their hybrids which use a single port wastegate and loose the twin scroll

Or, for simplicity and cheapness, restrict the exhaust system


Interestingly, like Kris I have a stock turbo, 3"DP, 3" flexi (which does have a sport CAT) and a 2.75 Blitz and suffer verrrrrrrry little creep
I have also been told that I'm special

I ran a ported wastegate and the backbox restrictor and had no boost creep issues but the porting took a bit of effort. With the restrictor removed I saw an additional 12bhp before the (essential) remap.

Does this make me 'special' as well

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Don
GT4DC Chairman
1994 Toyota Celica GT-Four ST205WRC JDM 269bhp @ 0.9bar
1994 Toyota Celica GT-Four Special GT 590bhp @ 1.8bar
1989 Van Diemen RF88/89 Formula Ford 1600
2008 Nissan Patrol GU 3.0L ZD30DDTi 154bhp

Just wondering out loud here but back in my Ford days we used to have boost creep due to the Garrett turbos W/G not opening enough, remounting the actuator (Was much harder then it sounds) enabled the W/G to open 90deg as opposed to the stock opening of 25 deg.
Does anyone know if the W/G opens fully??

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ST205 WRC #0002249

You're quite right Daz. Many of the aftermarket D/P's don't allow the wastegate to open fully. Some modification is often required.

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Don
GT4DC Chairman
1994 Toyota Celica GT-Four ST205WRC JDM 269bhp @ 0.9bar
1994 Toyota Celica GT-Four Special GT 590bhp @ 1.8bar
1989 Van Diemen RF88/89 Formula Ford 1600
2008 Nissan Patrol GU 3.0L ZD30DDTi 154bhp

First of thanks for the replys, and I wish i was special to:lol: I know in dosen't make a great deal of difference but mine is a 185 RC.

Will let you know how i get on with the exhaust bod when it get done next time I'm home.

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287 bhp / 254 ft/lb.
It's Orange and I love it

I have boost creep galore Hiflowed turbo and I don't think the wastegate was ported.

Wasnt that high flowed then was it
Can you send it back?? if not get a Dremel & DIY it

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ST205 WRC #0002249

Previous owner had it done... so I don't know

Shucks...

Dremel time, bring on the Dremel

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ST205 WRC #0002249

lol - thanks but no thanks lol

How much does porting out the wastegate help?

Luckily I haven’t had these type of problems yet so I don’t know, TrackToyFour & Sirius seem to be the people to ask tho.

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ST205 WRC #0002249

Managed to get the boost down from over 1bar to around 0.9. This might not seem much but at least it was then controllable by an EBC or aftermarket ECU like my MoTeC.

HTH

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Don
GT4DC Chairman
1994 Toyota Celica GT-Four ST205WRC JDM 269bhp @ 0.9bar
1994 Toyota Celica GT-Four Special GT 590bhp @ 1.8bar
1989 Van Diemen RF88/89 Formula Ford 1600
2008 Nissan Patrol GU 3.0L ZD30DDTi 154bhp