When my car is finished off in the next week or 2, I'll be dropping Kaz's GPX down to have a new exhaust put on. In doing so we are going to make a new collector pipe - from the headers to the cat. As we all know the standard collector pipe is very restrictive & the 2 banks join in somewhat of a collision point.
Now UAS have a product like this (pictured below) but @ $700 its not really the best bang for buck...
When we make one up for Kaz's car, if there is enough interest, i'll make a jig for it so we can churn out a number of these things at a reasonable price. We are also looking to do a deal where you can buy both the pipe & high flow steel cat to suit.
On its own, the pipe gives 4-5 atwkw gain, couple that with a high flow cat, you're looking at 10-12atwks. Its the best bang for buck exhaust mod you can do, short of replacing the whole system. I'll be doing dyno test results with Kaz's car.
It will be a direct bolt on fit for a GPX, and will only require a flange modification to suit a GR.
If you already have RPW extractors, then they wont be of use to you as they come with a good collector pipe.
So, if you are interested, let me know! I've not got prices yet & wont until we make one, but I'd say it'll be around the $400 mark.
