[davefr]

Will a downpipe with a high flow cat approximately equal the perf. gain of an "offroad" downpipe.

I don't have emissions testing to deal with but just wonder whether to buy the straight pipe or splurge and buy the high flow cat version.

 

[JZA80Supra]

get a Straight 4" downpipe(NO CAT), i have one on my car

 

[Rick1-10]

If you don't have emissions testing to deal with go NO CAT. It will be cheaper and faster.

 

[Silver Supra]

If you don't have emissions testing to deal with go NO CAT. It will be cheaper and faster.

Agree.
When I replaced my gutted cat (High-flow??) with open pipe, the difference was noticeable.

 

[supra_10]

Just remember that with no cat you get tons of exhaust fumes. That's the reason why I decided to go cat. That shit gives me head aches.

Jay

 

[theman]

I used the RT Hi-flo cat down-pipe and was still faster than one with a RMM off-road. Only difference in mods was mine had a FMIC and his was stock.
The hi-flo was way better than gutted stock cats.
Plus I'm a tree-hugger so I'm kinda partial to the clean running cars...