Using a FWD manifold in a 4AGZE set up

[92-GTI]

Hi All,

I was hoping that some one could either explain or direct me to some photos of the inlet side of GZE engines. I am a little confused and am trying to work out the plumming of the GZE engine works. As in where the one way valve is positioned in respect to the components.

I the reason i ask this is b/c i am wondering if a FWD AE92 manifold can be used as i think it would be better than the GZE one. I was also entertaining the idear or quads as i have a set. In addition to this I was thinking of starting to collect the bolt on parts to build up GZE. I was also planning to use the Eaton M90 instead of the toyota blowers.

Thanks Guys,

Ty

[Hen]

The GZE manifold is a pretty bad design, but they did that due to packaging constraints. Once you've got the intake pipe, throttle, blower, cooler pipes, etc in there, not much room is free to run a proper inlet manifold.

So yes, you can use an NA AE92 inlet manifold on a GZE (it all bolts up fine if you have a smallport head) you'll need to do lots of custom work to make everything else fit. Off the top of my head this would include:
- New SC top mount (usually mounts to the manifold)
- lean SC over to clear manifold
- New throttle -> SC piping
- New SC -> IC piping
- Blank off throttle from end of manifold
- Ensure the whole shooting match fits between block and firewall. It could well foul on something once you lean the SC to clear the mani.

Basically not worth the effort unless you are up for a big project.

Hen

PS, as for quads, most of the above applies, but then you need to consider you are moving throttle from pre-SC to post-SC aswell.

[92-GTI]

Thanks Hen for the reply. Is the STD GZE set up have the throttle body pre-s/c with a bypass valve. I need some diagrams and pictures to make it really clear in my head.

Thanks,

Ty

[92-GTI]

It does appear that turbo is the easiest way to go from scratch.

Ty

[Hen]

Ty a quick search of the tech section or members rides should turn up some good GZE engine shots.

Basically the intake layout is this: air filter -> intake pipe -> throttle (mounted vertically) -> SC intake (jammed between charger and block) -> SC -> IC -> inlet manifold -> engine.

It's a bit convoluted but I think it's not worth messing with unless you are keen for a big job. And as for going turbo, decide what you want. GZE will go straight in, GTE will require more time, effort and money.

Hen

[92-GTI]

What are the disadvantages of Or why don't they put the throtttle between the SC and the head?

[Hen]

If you mount throttle post-SC you need a good blow off valve. Basically at 7000rpm the SC pumps a whole lot of air, if you snap the throttle shut the SC is still spinning at 7000rpm* and still pumping that whole lot of air which now has nowhere to go. This will cause a HUGE pressure spike in the inlet tract and break something.

I think Ben Wilson or Nick Parker have set their ZEs up with post SC throttle, you'd be able to find more complete info by reading up on them.

Hen

[Sprinterboy]

I have a post throttle set up on my ZE

engine bay looks like this

[92-GTI]

Thanks for that photo. Do you also have a bypass valve or is the S?C on all of the the time?

Cheers,

Ty

I was thinking that the throttle before the S?C would have lag/response probems And i was hoping to avoid a blow off valve b/c i don't like them.