im re-building the manifold on my bike. I dont really have space (ground clearance) to have the runners come together in a square. I was planning on doing a 4-2-1 but everything ive read says to make sure its a 4-1 manifold. what are your thoughts?

 

I don't think it's gonna matter much on a bike with a turbo

 

how would it effect a car?

 

As far as waste-gate is concerned, you will never get the proper placement, as you need it past the end of the collector to get proper function, making for some horrible boost creep. Beyond that, I don't know the full extent of it.

 

the wastegate issue shouldn't be a problem for me, I have a funky setup. 4 cylinder (4-2-1), runners are about 30". the next step is about 9" to the final collector. then another 28" til they actually meet the turbo. I would have preferred the manifold be shorter but its on a bike and this way works nice. changing it would require be to fab out a oil relocation setup. also, my bike is naked so my little GT1548 would be embarrassing.

 

What bike is it? That turbo seems waay too small.

 

It's not, the turbo is specked. The bike only puts out 160HP however it's at low RPMs compared to most sport bikes. The only way im going to get more is to use water injection or relocate the oil filter and basically start over.

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