yesterday i cut the mufflers off my 90 model L-98. Now it will barely go 40, and falls on it's face when you try to accelerate. Will losing the muffs cause this? The car has been running a little rough before this. Could stopped up catalytic converters cause this? I appreciate any help you guys can give me!

 

yes.your cats if pluged up will make you loose power,even if pluged up will make car stall,,not start, loose power, why did you remove the mufflers, mufflers create backpressure and you need back pressure for the car to run better, and your car is desined for mufflers,or some kind of back pressure. on a drag car you do not need mufflers,[you will gain top end]and loose low end tourq, i would replace the cats and put back on your mufflers and see how it is,you can also do a simple check ,remove a o2 sencer and see if it runs better,by removing the o2 it will let out some exsuast of the pipes and the car should have some more power if u notice a difference then it is the cats for shure,and my question is to you did the car run like crap before you cut the mufflers off,

 

Well, my car had factory muffs and i want to put some flows on it soon, so i cut them off to see what it would sound like. It did start running a little rough lately, but now after cutting the muffs off it runs really bad. The weird thing is that after i cut them off it didn't change the sound of the exhaust. I'm going to check the backpressure on my exhaust system and see where that leads me. If i remove the o2 sensor to see if it runs better, do i leave it plugged in? Thanks for any help!

 

You don't have to leave it plugged in to test it, since it won't be making it into closed loop. The ECM doesn't look at O2 voltage until the car reaches closed loop.

 

hey, i had all three cats cut off and the muffler shop guy said they were stopped up like crazy. The car runs a lot better now, and soon i will have some flowmasters put on. Thanks for all the advice.

 

GLAD YOU GOT IT FIXED,I THOUGHT IT WAS THE CATS,GET FLOWMASTER DELTA FLOWS 3 CHAMBER,THEY SOUND GOOD,