Can a 3uz be run with a 1uz non vvti plenum / throttle body location?

[Mat Grant]

Hi all,

I've got a 1978 Lotus eclat with a 1UZ engine non vvti. It runs really well but I would like to increase the power/torque, through one of two options - 1 centrifugal supercharger at low boost (stock ECU), or 2 - change to a 3uz engine. It's a manual with a W58 Toyota box.

The problem is the Lotus has a very low bonnet line and needed a bonnet bulge for the 1uz.. But whereas the throttle body on the non vvti 1uz is at the side, the throttle body on the 3uz is at the front of the block - there is no space here on my car, as it has a front hinged bonnet that slopes downward.

So I could only fit the 3uz if I could run it with the 1uz non vvti plenum? Would I need the 3uz throttle body? Does anyone know if this would work? This would be with the stock ecu and wiring.

Any answers / suggestions welcome

Thanks, Mat.

 

[P Bateman]

Hi Mat - The short answer is no, the manifolds are not interchangable.

Both 1UZ non-vvti and 3UZ are 2-piece manifolds with and upper and lower section
The upper sections are not interchangeable and the lower sections (that bolt to the cylinder head) are different.

Looks like you'll just have to supercharge it. Or turbo.
In such a nice car though, I would not run the factory ECU. Whilst it can run with a supercharger, you definitely won't get the best out of it.
Forced induction has specific ignition and fuel requirements, and this can only be optimised by using a standalone ECU.

Most modern aftermarket ECUs can provide heaps more functions as well, other than just running the engine.

PB

 

[Mat Grant]

Hi PB,

Thanks for the quick reply - I've been trying to weigh up which is more difficult and which would result in the better car, performance, reliability, useability etc. It's a road car not a track car so I'm not looking for crazy horsepower, but a bit more would be good

I take your point about the aftermarket ECU though, I've been considering that for a while, not sure which brand of ECU would be best.

Mat.