I heard that by taking off my muffler I can actually lose hp. Is that true? Right now I just have straight pipes.

 

No, you did not lose any horsepower. But you definitely gained a little in the higher rpms over your stock muffler (as well as torque).

Mike

 

depends on the muffler and how it changes the waves.
-b

 

I thought you low end torque without a muffler?

 

You meant "lose" low end torque, correct?

No, you don't actually lose any torque by doing this (you actually gain like I mentioned above)...It just shifts the newer torque curve up a little in the rpm range, that is all...

 

I will learn to type one of these days.

 

A little torque here, a little torque there, it doesnt really matter, just so I gained something and it sound crazy good. I love the open exhaust sound of these engines!!!!!!!.

 

The factory exhaust manifolds and y-pipe give the LT1 all of the backpressure it needs. My car responded very well to cutting the exhaust off. Unless you have LT's with an oryp you wont notice anything lost but cutting your exhaust. With the LT's you might notice a little bit on the bottom end but up top it will be better than ever.

 

So what would you guys guess I have gained, if anything. I have the stock manifolds and I have the cat in there still. Did I actually gain any horsepower. I didnt do it for that, but it would be a nice bonus. I did it because I started the car to see how the new fuel pump worked, and loved the sound so much I didnt put the exhaust back on.

 

BLKLTTZ28, Can i ask you how you run a 13.4 @ 106 w/ just a k&n filter and a flowmaster muffler?? i have all my mods in my sig and im at 13.4 -13.3, i dont think i hit a 14.2 w/ a cai?? Explain.

Zach Horn

 

Ahhhh crap. I got all excited thinking someone had some hp numbers for me and it was a question for someone else. Ohhhhh the disappointment.

 

Looks like he can really drive a stick... lol but yeah, those times are definitely not possible for a filter and muffler. It's not even the CAI... it's just the filter, which doesn't do crap. I'd like to see the time silps.

Anyway, back on track....

Yes, you CAN loose power by taking the muffler off!!! It's called false knock. I can't believe that i'm the first person to mention this. The knock sensor MAY pick up the load exhaust as false knock. If it does, it will pull timing. I know this because my car does it when I open the cutout. Reving it to 6000 in park it pulls 17 degrees of timing. 3 degrees at 3000. OUCH! Yeah, im keepin the cutout closed, lol. Atleast untill I get the $40 for an LT4 KM.

 

So that knock module would take care of any false knock?? I dont need my timing retarded....my car runs retarded enough on its own most of the time.

 

These were my mods to run that time......


95 LT1 156k miles at the time

At Orlando Speed World, good weather, mid 70's, low humid.

TB bypass,
open airbox with home made ram air
cutout
MSD 6al
MSD coil and wires
LT4 KM
stock everything else

My best time before the MSD stuff and the cutout was 13.7 @ 104. That was with the flowmaster muffler and the k&n.

I have been told that I can drive stick pretty good. I am not saying I'm the best but I do alright.

 

Hmmmm, those M6's much make a HUGE difference huh

Zach