samssen

I got a Cattman Y-pipe, RT Cat, Greddy Cat Back Exhaust installed on my 2001 Max SE. I noticed that lossing low end torque on slow speed / low RPM. Gain a lot of high end power In higher RPM.

So I put on a Short Ram Intake to increase the air flow, also I think I can try to use a Apexi slicencer to restrick air not flow too much out?

mdloops

I would highly recommend putting the stock mufflr back on. This would add some backpressure depending on the design of the Greddy muffler. The stock muffler is a great variable flow muffler. You should not lose a single HP by doing this because the stock muffler is a variable flow muffler and when needed it will open all the way and reduce backpressure for high end power, but it will also add some backpressure at lower RPMs

You will notice a loss of power at lower RPMs with certain mods such as bigger exhausts. What size exhaust piping did you get? You should not get larger than 2 1/2 inch for a NA car with this engine. If you went larger (unless you have F/I) change it back to smaller piping. If you went with 2 1/4 - 2 1/2 piping you are just stuck with the loss of power. What you did was sacrifice a little low end for a little more higher end.

spirilis

iTrader: (2)

Please don't spread the "backpressure" myth... backpressure is NOT what gives you "torque", fast exhaust flow velocity is what does it. It just so happens that some exhaust systems which flow well for low-end torque build up excessive backpressure at higher RPMs.

A short-ram intake probably won't help your low-end losses much... try putting the stock intake back on, seal the scoop well against the airbox and try that?

And as mdloops said, don't use greater than 2.5" (2 1/2) diameter piping.