2001 SSEI, Mods Thrasher CAI, 3.4 pulley, 180 thermostat, NGK TR55,and MSD coils. I bought the downpipe & converter from hogan performance. I don't want to put it on if I lose bottom end. Also does anyone sell ported exhaust manifolds for my car. Thank you

im confused to what you are asking?

you bought what already? the DP or the cat?

i would have recommended gtpowderworks.com to you 6 months ago, but not anymore, very iffy service if any

Hey Jim.

There are some here that have put on the 3" downpipe, but as far as I am aware it is not necessary since the stock downpipe handles plenty of flow. I would say that others could offer better input on this or do some extensive searching, since I believe there are some discussion on this subject already. The hi-flow cat is a recommended mod though and I have not heard of anyone losing bottom end with that.

I am not aware of any company that has off-the-shelf PEMs for our cars. Most here have either had them done locally, done them personally, or used a company like gtpowderworks. Andrew just had a tough time with them, but it is my understanding that their product has usually been pretty good and reasonable. You must not want them in a hurry though, as it usually takes months for them to finish a set for you and you have to provide the cores up front in most cases.

I suspect that there are other options but cannot think of any others at this time.