slyws6

Ok here's the deal, I had Stainless steel true duals installed about a week ago. I noticed a big diff in bottom end, mid range and I thought top end. I raced a friend of mine and noticed my top end kinda sucks now. Here's my idea of why, I had a 3in y-pipe before well they cut the y-pipe and hooked up the 2 1/2 in duals to where the piping comes off of the headers. On the drivers side there is about 2ft of 3in pipe that connects to 2 1/2in , and about a foot on thd pass side of 3in that connects to the 2 1/2 in. Because the 2 1/2in was inserted into the 3in and then welded could this be causing a big drop in flow. I noticed when revving in neutral that between 4k-redline the engine stumbles and acts like it's hitting the rev limiter. I'm guessing due to restrictive flow. Do you think if I have the cats removed and the 3in pipe removed and have straight 2 1/2in coming off the headers and all the way back that will help? Thanx.

-Sly

HOTROD98Z

iTrader: (1)

Yeah something is not right, I would think with the duals you should have gained throughout the entire powerband just not down low. I have read before on here that people running a reducer and not having a smooth transition causes too much turbulance inside the pipes thus causing problems. Maybe someone with firsthand experience will chime in.

HOTROD98Z

iTrader: (1)

Oh yeah get rid of the cats they are evil.

slyws6

cool, thanx for the reply, I'll be getting rid of the cats tommorow

onebadz

Just a ?, why didn't you go with 3", I think you would of saw a signifigant gain up top but might of lost a tiny bit down low. Of course when are you ever racing in the lower RPM's. Get rid of those cats and tell us whats up. Good Luck

Wes

FAST LS1

iTrader: (2)

The turbulance might be causing the O2 sensor to get false readings since the gases aren't flowing correctly. I'd get a smooth reducer from 3" ro 2.5" welded in since they are pretty cheap.