need exhaust advice
need exhaust advice i recently put h/c on my SS and an having exhaust leaks an need to replace my cats . My question is how much power will i lose if i go from a 3" catted y from TSP to a custom ball and flange style setup with 2.5" catted y to a flowmaster 2.5" to 3" merge collector? I really like the idea of a bit more clearence but not if its gonna cost alot of hp/tq. Either way i want to switch to a ball type flange to eliminate exhaust leaks im having with the band clamps. So please shed some light on my current delima. Thanks in advance.
There are two main considerations to take into account. Once you remove the factor of fitment, you want to make sure for reference purposes the goal is to keep a meaurable amount of performance gain, still left in the potential of the system. That being said, a ball and socket type flange connection is only as strong as the weakest link. In other words if the flow for the inner diameter is compromised more than a minute percentage of the 2.5", it's going to cause a noticeable restriction. If I were you I would install the high flo cats and still run the smooth collector. Just be careful with placement of the components such that there is more clearance than before, as you already mentioned. Although it would be easier to say what the estimate is, it would be more difficult to put a number on what exactly would be the tangible difference.
Oh, ok, sounds super nice. All the best. 
It wouldn't add up to that much just take an estimate of it, run some numbers around and come out with a few hp lost if that, and you have an opportunity to clean up the connections, do that and you're all set.
Originally Posted by gr8one99SS
i wouldnt mind changing to a 2.5 pipe if i thought i would lose a maximum of 8-10 rwhp. do you think i would gain or lose hp/tq down low under the curve?
