Different stock manifolds for an Ecotec

[mart154]

Hi there.

Im searching some better suited stock exhaust manifolds for my VT turbo project.

My plan is to flip manifolds (or at least the passenger side) upside down, but the stockie is a bit too long from the exhaust side, leaving me a bit out of room to mount the turbo.

Is there any chance that I could find better suited items from another model?

I mean:
1. that have shorter "tube" on the exhaust side OR.
2. the "tube" comes out straight (facing straight backwards, when mounted correctly)


Thanks in advance.


Don't really want to know that stockies are crap, I know that already
But for my application they are way good enough as different projects ive done before have proven.

[westerlybreeze]

My plan is to flip manifolds (or at least the passenger side) upside down, but the stockie is a bit too long from the exhaust side, leaving me a bit out of room to mount the turbo.

Hi there,
I used two passenger side VT manifolds. I cut off the flanges and welded 2" ID welding elbows (by preheating first). Placing the T4 turbo close to the passenger side head.
I crossed over from the drivers side in front of the motor including a flexie (for heat expansion) to the turbo flange on the passenger side.

A few problems with this arrangement:
1st The passenger side, using a flipped passenger manifold doesn't exactly line up - bolt holes will need slotting and some grinding to make it fit.
2nd There maybe an issue with gasket sealing and blowing out the gasket.
3rd Also the spark plugs on this side are a b@st@rd to get to with this manifold.
4th Factory cast steel manifolds crack without a turbo... so be prepared to fix em.

If I ever turbo again.. (there's always the chance) - I'd fabricate tubular manifolds or get some of those Proflow? ones

[klampy]

have you tried getting one of the american FWD manifolds n having a look? they run the Xover over the top of the trans i think... but that means that if you flipped it that it would be facing straight forwards???

only an educated guess but may well be worth looking into. something like a buick regal or similar...

[westerlybreeze]

have you tried getting one of the american FWD manifolds n having a look? they run the Xover over the top of the trans i think... but that means that if you flipped it that it would be facing straight forwards???

only an educated guess but may well be worth looking into. something like a buick regal or similar...

I'm pretty certain the Buick is different, maybe even more so than the Series one VN-VR motor.
Look out for an GM 3800 L36 (NA) or L67 (supercharged) manifolds. Pontiac GT or GTP late '90's -2004 I think.
Have a look at ZZP or Intense in the States, eBay or google em
Probably easier to make some though.

[mart154]

Hi there,
I used two passenger side VT manifolds. I cut off the flanges and welded 2" ID welding elbows (by preheating first).

Just wondering, why didnt you use the drivers side manifold on the passenger side when you welded them anyways?

Thats what I actually planned to do but thaught to give a look on other manifolds before....

How was the manifold to weld? Ive seen two types of cast alloy manifolds in terms of welding. Some are pretty good to weld and stay together pretty good. Others are crap, the weld comes all full of bubbles and weak as shieet.

[westerlybreeze]

Just wondering, why didnt you use the drivers side manifold on the passenger side when you welded them anyways?

Thats what I actually planned to do but thaught to give a look on other manifolds before....

How was the manifold to weld? Ive seen two types of cast alloy manifolds in terms of welding. Some are pretty good to weld and stay together pretty good. Others are crap, the weld comes all full of bubbles and weak as shieet.

Not sure exact reason for not using the drivers side one reversed on the passenger head.. must of been a good reason I hope

Re welding.. pre-heating would help to stop it cracking from heat distortion. I TIG welded them with a stainless steel filler rod.. one manifold did crack after about 12mths
(.. not where I welded it, cracked where they usually crack)

I'd still recommend fabricating some from welding elbows

[mart154]

I'd still recommend fabricating some from welding elbows

Im lazy, maaate

[westerlybreeze]

Im lazy, maaate

Go buy a V8

Half the fun is tinkering yourself! I bet all these fellas on JC aren't "lazy maaate"

[mart154]

Ok, just had a look under a VN hood. It seemed to have steel manifolds that would be a lot easier to modify. Do these bolt onto ecotec?

[westerlybreeze]

Ok, just had a look under a VN hood. It seemed to have steel manifolds that would be a lot easier to modify. Do these bolt onto ecotec?

Nope, port spacing is different. They don't flow that well either.. have another look, see those right angles? no good for flow dude.

[mart154]

Ok, where to get ecotec manifold flanges

Does anyone sell them or i have to make a cad drawing and go to laser cutting?

[klampy]

if you get them laser cut just go get a gasket from repco/autobarn/bursons. etc... and when i referred to buick, i meant the GM3800 engine. the buick regal has the same motor. it was more of a generalisation by calling it a buick since thats what it essentially is.

[Pub247]

Nope, port spacing is different. They don't flow that well either.. have another look, see those right angles? no good for flow dude.

If your doing the early buick theyre a cheap way to get out getting flanges as the S1 vn's have welded manifolds. Though theyre a little on the thin side. My mate has made a set of turbo manifolds using them though

As for laser cutting I have CAD drawings i will sell them cheaper than a laser cutter would charge to draw them best getting 12mm+ thick flanges