The Green Monster Project - Stroker GT30

[Faheemo]

Time to start my Project thread about my upgrades to my S2 (aby) Coupe.
My previous setup with a Gt3071 turbo made close 450hp on the crank.
But very soon after this i melted a piston , when i had a failure on the WGFV.

My new setup will look like this if all goes to plan.

Stroker 92.6mm crank
JE pistons 82.5 mm 8.5 compression ratio
Garett GT30 Ball bearing turbo
Wagner reverse intake manifold.
RC engineering Injectors 750cc
intake and exhaust 7a cams
flowed head with oversize light weight valves
Huge Intercooler
Cooling mist water injection.
high rate valve springs
Koni & H&R combo
Porsche GT3 big brake conversion with porsche hats.
18 inch RS4 Mags

Hoping to make close to 550hp with this setup.

Melted Piston - 2.4bar with stock compression.

[vonbeck]

good luck with the new project and keep us posted

[A80Avant]

can you explain the WGFV problem that created this mess??? what did you see on the EGT?how long were you going 2.4bar?

[terrybullwon]

You done that piston well!!!

Good luck with your new set up looks like it should be good

[donce]

so it went to 2.4 bar after wgfv failed yes? how much boost were running when it was ok? anyway,good to see starting a new project

[s2 rich]

nice thread looks like a good one what will you be doing with your old un used and un loved gt 3071 ??? i know a good home for one

[Jamo]

Nice project, stroker in the standard block
you dont really need the heavy duty valve springs as you can't go above 7.5k rpm

Seriously good work on melting that piston!

[terrybullwon]

Just out of interest what head gasket are you using with the 82.5mm pistons?

Cheers James

[aronmatic2]

if you finish this project, you will have lot of smile on your face after every minute driveing.

[Faheemo]

3071 was sold to fund my new turbo !
I was looking for 2.0 Bar Boost on the bigger turbo, and the car just could not hold 2.0bar . Could not find the leak until i disconnected the WGFV and realised the WGFV was leaking - was ill advised to use a tap to control the boost. The boost over shot on 2 runs i did trying to log EGT and AFR.
The 2 runs maybe lasted a total 15 seconds combined.
I Heard the detonation - didnt realise what it was - i was still wondering what the hell i didnt tighten in engine bay when the oil ring when kaboom.

good that nutting else broke

Had the high rate valve spring lying around b4 i melted the pistons - so what the hell throw them into the new setup.

Opened the head to see this was terrible.

[Faheemo]

No Serious Worries though - JE made me a new set of new pistons - Javad @ 034 hooked me up with the head gaskets needed - but its just a standard rs2 spec metal Head gasket - gotta see to the 82.5mm issue.

BTW my previous set of pistons where ceramic coated - looked like this b4 the meltdown.

[4WheelDrifter]

Ouch! An expensive way to find out that standard CR doesn't like >2 bar.
I like the way you are turning a negative into a positive situation. A good excuse for another upgrade.

I've read somewhere else about N75s leaking, that's worrying.

[Faheemo]

GR8 Reason to go all Out !!
compression was slightly lower than standard, i had the previous standard pistons machined down.
See here for the details on the car pre meltdown.
http://www.audiclubsa.org.za/cgi-bin/yabb2/YaBB.pl?num=1138705305

http://www.audiclubsa.org.za/cgi-bin/yabb2/YaBB.pl?num=1138705305

The New pistons are beautiful ! wont be ceramic coating these - waste of good money if you ask me.

[4WheelDrifter]

The New pistons are beautiful ! wont be ceramic coating these - waste of good money if you ask me.

[Faheemo]

Got my mate to pull the engine out, and take over the engine repairs.
Searched the breakers yards until i found a good crank, from a 2.5Ltr VW microbus (transporter). 92.6mm stroke.

@ Jamo - I recall reading from Marcos stroker post that 92.6mm crank on 220mm block is capable of revving to 8500rpm safely. have you done the math on this ? - I havent. Other wise i have just wasted alot of money on a good head job for my car.

* Faheemo goes to pull out calculator and sharpen pencil *