Hey Everyone,

I'd like to get an idea of the big difference with respect to power gains and sound increase between either installing RRM's High Flow Cat or simply using the Cat Eliminator? Can the High Flow Cat fit on our stock Ralliarts? Mine is the 05 model. If so, would we see any performance gains, increase in sound? What about the same, but using RRMs cat eliminator? Thanks

 

I'm told the diff between high flow cat and no cat at all is like 2-3 horses. I think everyone can agree that cat vs no cat at all there is definately a gain to be had, I can only assume that the high flow cat would feel very similar to no cat - from what I have read. I do know that having no cat at all will make you nice and quiet. and by quiet I mean not at all.

 

so are you saying I should see gains with just a high flow cat? I've heard that by taking out the cat the car get get extremely loud and I don't want that.

 

yep i took out my cat, but installed RRM's downpipe which acts as a cat delete. Its extremely loud, but i heard that with the restricted stock Downpipe and a highflow cat sounds worse. So mabye u should go with RRM downpipe and their hight flow cat, and then a catback. It does really sound better with all those together.

 

I just put in the RRM downpipe last weekend and the stock muffler can't handle the extra flow. You can hear the baffles vibrating under WOT. I already ordered the high flow cat from RRM and expect the car to still sound better than stock, but not have vibration in the muffler anymore. You can expect gains over stock of 10+/- hp with the downpipe and no cat and 7+/- with a high flow cat. The factory downpipe is not mandrel bent and has a crimp point where it bends to the back of the car, so just putting in the test pipe will probably gain you at least 5hp, but if you have the money you should do something about the restriction in the piping too. Search on the exhaust systems getting ready to come out by RRM and RPW before you decide what you want to do though.

 

Has anyone tried the cat eliminator from RRM? I'd like to try it, but worried about how loud my car will be with it. Can anyone comment on the noise and power after installation? Thanks

 

if you want a nice sound go with a muffler (megan racing!!) heard one i have to order one haha..

 

Therez NO way around it, you are going to be much louder than stock. Probably the best setup with sound consideration would be complete RRM exhaust setup from header to muffler with the high flow CAT + resonator.

I used to just have the downpipe + axle back, and damn was it loud. I had a Magnaflow resonator welded on , and that helped quite a bit.

 

The stock piping for the car is pretty big 2 1/8 and the stock resonator hardly doen anything to silence it. Just upgrade your piping to a 2.25 and add a decent resonator(NOT TOO DAMN BIG)...Dont get 2.25 press bends like me, youll end up restraining your car more than stock