Would an aftermarket OBX header add significant hp and torque and would the sst or heated oxygen sensor be effected by this swap??? ?

 

No and no.

 

please don't get obx.

 

what would you suggets as a modification to increase torque???

 

a v8

 

are there any aftermarket headers worth getting??? Thanks.

 

I have the OBX header and can only say that it is very poorly designed and also is not a good fit for the Renesis engine. The exhaust port size on the OBX are not a match to the Renesis exhaust ports. e.g. The two outside ports on the Renesis engine are considerably wider than the centre port but this is not the case with the OBX header.
The OBX header ports are all the same size i.e same as the centre port. The OEM exhaust header port dimensions are: Centre Port= 53mm high x 24mm wide and the two outside ports are 53mm high x 37mm wide (approx).
Added to the above the OBX header has not got provision for the secondary air pump to function as it was originally designed.
I guess you get what you pay for in this instance.
I cant say if any aftermarket header can give more torque or horspower?

 

In all seriousness mods don't do much on the Renesis. You'll spend a lot and get fairly little. The best way to increase torque is to go forced induction such as a turbo kit.

 

but wouldnt an aftermarket header be benificial with a Fi kit? s/c or turbo? it may not do much on an NA engine? but wouldnt it add significant Gains on a FI'ed Car???

 

A well designed one would, but so far no one has come up with a good design. A well designed header would be beneficial to both NA and FI. But, only if the OEM header was of an inefficient design. The only thing you get with the OBX header, from what I've heard, is the loss of a few pounds.

 

What aftermarket header other than the one that comes with the Greddy kit will fit a t618z? I'd like a stainless steal exhaust manifold/downpipe wrapped with a heatshield rather than my cast iron Greddy one but I'd have to get one custom made.

Like rotarygod said, FI is the only way you can get real torque numbers. I hit 245tq at 10psi on my last dyno run.

 

Going with a bigger turbo will require it to be in the engine bay because of the location limitations where the Greddy turbo is.

 

That was a hypothetical question.