Hi gents,

Just in the middle of redoing my exhaust manifold as its too close to the pedal box cylinders for comfort. The plan now is to have the manifold going over the top rail instead of out the side pannel.

As it stands it will go from the head flange into long 90° bends over top rail, into back turned 45° bends into a 4-1 collector. The primarys are all 42mmx1.5mm stainless.

Q1. Would I be better off having a 2.5" or 3" outlet from the collector (supercharged 2.3 will 250hp+). Or should I run 3" and reduce it down to a 2.5" bore silencer? Don't want it to be so loud that I don't enjoy driving it.

Q2. Would a 3" pipe likely be too loud for the IVA test or should I look into pipe inserts to bring the DB down?

Q3. The O2 sensor bung, is the location/angle important? I'm guessing anywhere between the collector outlet and silencer would be OK?

Q4. I'm looking at using a universal silencer from the bay-of-E, preferably 6 or 7" in diameter, however the longest I can find is 22" will this be big enough? Lots of the ones I see online are about 1m long.

Cheers,

J