New project brings lots of questions, help please

[WagonWheel]

Hey guys,
Just bought my new project which is a tidy as GE siggy, 2.0, 57,000s k's on the clock, jap 5 sp etc etc. Wicked starting ground if you ask me.
Basically the plan is to go EFI turbo.

At first i was planning on just going the magna motor and get it freshened up and drop it in, but i picked the car up last night and was so wrapped with how it drove. Engine doesn't skip a beat. Soooo smooth and doesn't make any noise at all.

Firstly i need to know if Ive got the narrow block or wide block in my GE? Cause that will pretty much make my decision, how do i tell?

Next i need to know what sort of comp ratio i will get with the GE block with magna head on it? I had a GK siggy turbo with astron 1 block with astron 2 head and it was grumpy as all hell because of low comp. Could i raise it enough to be friendly driving but also boost friendly by just shaving the head to raise comp a bit? If so by how much?

I would like to stick to the standard 2.0 because it'll be good to have a matching numbers car for rego and what not down the track. But also presume there's more power to be made out of the Magna 2.6?

Also what sort of size turbo would be good? I don't want a little peanut turbo, but i don't want something that has to wait til 5,000rpm to spool.
And how do i get in touch with stealth about a turbo manifold? He wont reply to my PMs

What sort of specs cam should i go with?

Anything else i should consider? Ive pretty much got my mind made up about fuel pumps and ecu already

Also if any ones got any bits for sale that i might need or be interested in feel free to PM me.

Cheers
Geoff

[colta51]

it shood be a narrow block but you can tell by messuring the top too bolts on the bell housing to the motor thay shood mesure 120mm apart to be a narrow block..

[WagonWheel]

Thanks, ill go measure them this arvo. Any idea on any of my other Q's?

[WagonWheel]

The very top bellhousing bolts were 130mm from centre of bolt to centre of bolt

[75wagon]

Firstly i need to know if Ive got the narrow block or wide block in my GE? Cause that will pretty much make my decision, how do i tell?

You tell by the fact that all 2.0 4G52's are narrow block.

Sounds like a good start to a project, but just a quick question: if it's only got 57000km's on it, why would you want to mod the car? Me personally I'd be looking at bolt on mods only with a car that original (but it's your car so you can do as you please), please keep the original parts so they can be sold with the car if you ever sell it, to give the next owner the choice whether they want to restore it back to original.

How about some pics?

Dave...

[webby]

+1, keep it original unless it's all easily reversible

To answer your questions,
you'll need to get a couple of mm taken off the Magna head to get the comp chambers right for the 2L block, but it's doable afaik. No idea on the comp ratio though.
T28bb off an S15 should be fine
Stage 1 cam would be fine for a stockish turbo motor

I think. Someone who's actually done a turbo motor before will have to confirm. 2L are all narrow though

[WagonWheel]

Thanks guys, when i was driving it home yesterday it actually did make me want to just keep it original. But seriously... i cant have a slow car. The whole point of buying it was to do this. I will keep it 99% original looking, exterior and interior, i just want to put sigma turbo wheels or pepper pots on it and thats about it.

Heres a quick pic of it from when I had just got it home yesterday, i will start a new build thread with better pics soon. Just after some more answers on this thread though.
Cheers guys, any more help greatly appreciated

[13bsigma]

very good mate. i really wanted to buy this, but i'm in the gold coast and already have a 58,000km one. glad to see it will still be on this forum.

[Sigmoe]

ahah great buy, i missed out on this also
plan sounds good , keep us updated with lots of pics!

[WagonWheel]

Thanks guys, really need some more answers too if possible.

Before i ask these questions i will insist i have been searching through the forums for the passed few hours in fact.

Balance shaft elimination: Do all 4g52s have a balance shaft? I have seen some related to non balance shaft 4g52s and most of the info i come across the kits relate to the 4g54. In particular im referring to my GEs 4g52 obviously.

Im pretty much set to stick with my stock motor but convert to magna head and injection. But will compression be much of an issue? I know i could get the head shaved, but by how much and what sort of compression will i expect to see? I dont want it to be a complete pig down low, but need it to be boost friendly.
With the magna head? Which head should i go for? Ive heard M6 or M7, however im getting conflicting views on what to do with rocker and cam gear. Keep the Magna stuff or use the GE gear? I will be putting in an aftermarket cam too by the way if that makes a difference.
Will i need forged pistons or will the standard dished sigma ones hold relatively low boost (12-15psi maybe?)

[WagonWheel]

Ignore the balance shaft question, sorted that out and ordered a kit today for $25 from work.

Really need to know about the head and compression issues though

[karl_2ltgc]

Why no just go for a EFI 2.6....

Wont be 'fast' but it will stay infront of your average v6 commodore....

Going all crazy with turbo stuff often just highlights other problems with the car.

[Superscan811]

Why no just go for a EFI 2.6....

Just for comparison..
GH Compression Ratios
2.0L turbo was 7.8:1
2.0L NA was 9.5:1
2.6L NA was 8.2:1

Magnas
TR/TS Carby are 8.8:1
TR/TS EFI are 9.2:1

US Starions (2.6L turbos) are around 7.8:1

Cheers.

[WagonWheel]

I under stand what your saying about just going 2.6 efi but that's by why I bought this car at all. This car will be turbo. And I don't really see the thrill in trying to beat a stock commodore v6

Thanks for those comp ratios but really need to know what comp I will get if I use my 2.0 block with efi head. And if it's too low how much do I need to shave off the head to get it back up around the 7.8:1 mark?