which cat bypass
 

I am looking to fit a down pipe on 93 ra but not sure which one, the open neck or the one that has the waste gate blanked off. Any ideas chaps.

Cheers

yes get the open neck style man, get it out asap ;)

Any reason to pick one over the other?

Open necks are fine, and the ones you can buy with the wastegate blanked off work really well too, I have one on my 94 STi RA, made by MEGAN, this design I believe were made to eliminate boost spikes, and I have been told that they have been used on bigger BHP motors without any loss in power compared to the open neck design.

I use a HKS closed neck DP on my STi4 making 383/340 without any problems, I've also been told that they help control boost a little better than the open neck design.
It's another SN myth that you need a open neck DP to make good power.

Ok cheers for info mate