3S-GE/GTE mix and match?
Posted: 05/03/18 11:27
I was thinking last night... with 3s-ge engines not worth that much, could I use any parts from the engine coming out of the new shell to enhance the 3s-gte that will going in? We're talking gen3 3s engines in both cases (in fact both from rev3s).
Two plans came to mind:
1) Use the entire GE head on the GTE block
This assumes that the GE head flows better, especially with it's larger lift cams and that is beneficial. It would also come with the bonus of a side feed manifold, negating the tendency of cylinders 2 and 3 to run lean on the GTE manifold. You'd also get the 70mm throttle body compared to the GTE's 60mm. I believe the exhaust manifold will bolt up, making hanging the turbo pretty straightforward still, and using the GTE block would mean there's already an oil feed waiting for the turbo.
The main issue I can see is injectors; the GE uses top feed while the GTE uses side feed, meaning you may not be able to fit the GTE injectors straight onto the GE head.
I had been thinking you would also need to rework the idle control too, as I had thought it simply diverted around the throttle butterfly and would still be injecting pressurized air on the overrun. However, looking at the workshop manual, I think there's a separate ICSV line which could be plumbed into a non-pressurized part of the induction tract.
2) Use the GE cams in the GTE head (and maybe the intake manifold)
With bigger lift and duration, the GE cams are often touted as a performance upgrade on the GTE, but I don't think I know of anyone in the UK who's done it. Obviously I'd need to re-shim all 16 valves.
In the past I've also researched the GE manifold as an easy side feed option for the GTE head, and found forum posts suggesting it doesn't bolt up. However the gaskets are the same part number so I still wonder if it will bolt up.
Also...
With either plan, although I'd hope to start with a "stock" ECU, to make the most of cams, alongside my GT2860RS an aftermarket ECU is going to become a necessity.
I'm guessing others have thought about all this before... thoughts are welcome
Two plans came to mind:
1) Use the entire GE head on the GTE block
This assumes that the GE head flows better, especially with it's larger lift cams and that is beneficial. It would also come with the bonus of a side feed manifold, negating the tendency of cylinders 2 and 3 to run lean on the GTE manifold. You'd also get the 70mm throttle body compared to the GTE's 60mm. I believe the exhaust manifold will bolt up, making hanging the turbo pretty straightforward still, and using the GTE block would mean there's already an oil feed waiting for the turbo.
The main issue I can see is injectors; the GE uses top feed while the GTE uses side feed, meaning you may not be able to fit the GTE injectors straight onto the GE head.
I had been thinking you would also need to rework the idle control too, as I had thought it simply diverted around the throttle butterfly and would still be injecting pressurized air on the overrun. However, looking at the workshop manual, I think there's a separate ICSV line which could be plumbed into a non-pressurized part of the induction tract.
2) Use the GE cams in the GTE head (and maybe the intake manifold)
With bigger lift and duration, the GE cams are often touted as a performance upgrade on the GTE, but I don't think I know of anyone in the UK who's done it. Obviously I'd need to re-shim all 16 valves.
In the past I've also researched the GE manifold as an easy side feed option for the GTE head, and found forum posts suggesting it doesn't bolt up. However the gaskets are the same part number so I still wonder if it will bolt up.
Also...
With either plan, although I'd hope to start with a "stock" ECU, to make the most of cams, alongside my GT2860RS an aftermarket ECU is going to become a necessity.
I'm guessing others have thought about all this before... thoughts are welcome