Is there any difference between 2wd and 4wd plenum chambers?

I know the later EEC escort ones are different but were they changed on the weber equiped cars?

If so, what are the differences?

 

the 4x4 plenumn has a bolt on elbow for the throttle body where the 2wd version is cast into it already iirc

 

Im not aware of any differences to the chamber themselves, but the throttle and fuel rail fittings are different.

 

the other way around,,, a 2wd has a bolt on elbow

 

Ahh... two conflicting answers!!

 

Why do people switch to a 4x4 plenum around 450hp then ?

Surely the escort cosworth plenum is just the better one to use ?

 

Due to the elbow I guess mate, personally I would go for the eec one though if bothering to swap.

 

Well I'm hoping for around 450hp, I did read something MikeR put about not over speccing stuff.

He said that the 4x4 setup was better for around that h/p then anymore you would want the eec iv.

I presume there is nothing useable from the 2wd manifold if I went down the route of using either of the other manifolds ?

 

Manifold from the 2wd will direct fit the 4wd plenum mate.

 

I'll keep any eye out for a plenum then mate, cheers

 

Yeah spot on, just sold my spare 4x4 one.

The difference is in the throttle elbow and thats where the restriction comes from. You can open this up by having a plate welded on the outside and cutting away the rest, this with a plenum spacer and its good for over 500bhp.

Escort ST one is good if dont want more than 480bhp, trying to find one is the fun part though.

 

As said, 2wd :

 

Does the 2wd throttle body fit the 4x4 and EEC IV plenums ?

 

It will fit straight onto the 4x4 plenum, but needs the 4 mounting holes drilled out from 6 to 8mm to fit the EECIV plenum. If you want to improve matters further, you could chamfer the end of the throttle body (IIRC approx 58-60mm) to match the diameter of the inlet of the EECIV plenum (approx 64mm)