Hi guys,

I am in the process of rebuilding a 3.0 V8. Don't tell me "USELESS BUY A 4.0" I simply want a rebuilt 3.0 behind which I will fit a strengthened 5HP30 and SOMEWHERE in the future I will go 4.0.

Now I have a 4.0 air intake, 4.0 throttle body, 4.0 MAF and 4.0 filterbox.

I had an air leak on my throttle body of my current 3.0 (470.000km) engine. Engine runs great, almost ZERO oil consumption so untill I have the rebuilt engine ready I keep doing small maintenance on it.

The air leak was on the gasket behind the throttle body so I got a new gasket and decided to go immediately to 4.0 size. I have done the following:
- fitted the 4.0 throttle body on a 3.0 manifold (plenum modifying piece still in the 3.0 manifold);
- fitted a 4.0 MAF that is still ok;
- fitted a 4.0 upper air filter box piece;

The car runs fine and better since I no longer have my air leak. I will still have to modify my throttle cable a bit but my general idea is the following:
- the pickup from idle / standstill is a bit slower;
- I think I have more power in the higher RPMs;

Intervening variables are:
- still need to adjust my throttle cable a bit;
- I am using a different MAF sensor (identical number of sensor but a different piece);

I have fit my own MAF sensor (bought it new 2 years ago Bosch) in the 4.0 MAF house (Bosch too) but the car won't run well on that combination. THIS IS ABSOLUTELY WEIRD BECAUSE BOTH MAF SENSORS ARE IDENTICAL IN PART NUMBER, SIZE, AND LOOKS. IT IS JUST THE MAF TUBE THAT IS BIGGER ON THE 4.0.

I will adjust my throttle cable and I will buy a brand new MAF sensor to place in the 4.0 tube.

My question is, regarding a 3.0 M60:

Being able to combine any Manifold piece + Plenum piece + throttle body + MAF + upper airbox piece of 3.0 and 4.0, what combination would give me what kind of performance?

What will theoretically give me the best low RPM pickup?

What will theoretically give me the best high rpm power?

If I fit the 4.0 intake on my rebuilt engine, would I want to use the 3.0 plenum piece?