Muffler question, exhaust changed
Thread Starter
Burning Brakes
Joined: Sep 2008
Posts: 772
Likes: 4
From: Ottawa ON
Muffler question, exhaust changed
I changed many parts over the Winter. I want to know if those mods would benefit from a few extra mods.
What I have done so far:
Halltech CAI and beehive
FAST 102
1 3/4 ceramic Kooks headers
Highflow Cat and xpipe, 3 inches.
The 3 inch xpipe goes down to a 2 1/2 inch at the end to go with my stock mufflers. Are the Z06 axleback all 3 inches? Would I benefit going to a 3 inch axle back (from end of Xpipe and the muffler?) If I would benefit, I would cut the reducer to 2 1/5 off and just put all 3 inches, but only if there's definite improvement.
Another possible restriction in the system is the stock LS2 MAF sensor. It's the most restrictive part in my air intake system, followed by the throttle body. How much benefit is there to switch to a LS3 or Z06 system of MAF?
I'm getting a tune done this weekend, with those 2 restrictions in place, wondering if I'll need a tune again if I ever get rid of those restrictions.
What I have done so far:
Halltech CAI and beehive
FAST 102
1 3/4 ceramic Kooks headers
Highflow Cat and xpipe, 3 inches.
The 3 inch xpipe goes down to a 2 1/2 inch at the end to go with my stock mufflers. Are the Z06 axleback all 3 inches? Would I benefit going to a 3 inch axle back (from end of Xpipe and the muffler?) If I would benefit, I would cut the reducer to 2 1/5 off and just put all 3 inches, but only if there's definite improvement.
Another possible restriction in the system is the stock LS2 MAF sensor. It's the most restrictive part in my air intake system, followed by the throttle body. How much benefit is there to switch to a LS3 or Z06 system of MAF?
I'm getting a tune done this weekend, with those 2 restrictions in place, wondering if I'll need a tune again if I ever get rid of those restrictions.
Race Director
Joined: Mar 2005
Posts: 10,399
Likes: 26
From: Austin Texas
I changed many parts over the Winter. I want to know if those mods would benefit from a few extra mods.
What I have done so far:
Halltech CAI and beehive
FAST 102
1 3/4 ceramic Kooks headers
Highflow Cat and xpipe, 3 inches.
The 3 inch xpipe goes down to a 2 1/2 inch at the end to go with my stock mufflers. Are the Z06 axleback all 3 inches? Would I benefit going to a 3 inch axle back (from end of Xpipe and the muffler?) If I would benefit, I would cut the reducer to 2 1/5 off and just put all 3 inches, but only if there's definite improvement.
Another possible restriction in the system is the stock LS2 MAF sensor. It's the most restrictive part in my air intake system, followed by the throttle body. How much benefit is there to switch to a LS3 or Z06 system of MAF?
I'm getting a tune done this weekend, with those 2 restrictions in place, wondering if I'll need a tune again if I ever get rid of those restrictions.
What I have done so far:
Halltech CAI and beehive
FAST 102
1 3/4 ceramic Kooks headers
Highflow Cat and xpipe, 3 inches.
The 3 inch xpipe goes down to a 2 1/2 inch at the end to go with my stock mufflers. Are the Z06 axleback all 3 inches? Would I benefit going to a 3 inch axle back (from end of Xpipe and the muffler?) If I would benefit, I would cut the reducer to 2 1/5 off and just put all 3 inches, but only if there's definite improvement.
Another possible restriction in the system is the stock LS2 MAF sensor. It's the most restrictive part in my air intake system, followed by the throttle body. How much benefit is there to switch to a LS3 or Z06 system of MAF?
I'm getting a tune done this weekend, with those 2 restrictions in place, wondering if I'll need a tune again if I ever get rid of those restrictions.
Thread Starter
Burning Brakes
Joined: Sep 2008
Posts: 772
Likes: 4
From: Ottawa ON
There's a science behind this, and I don't know how to calculate it. Knowing everything before the rear axles is 3 inch, then goes down to 2.5, I am left wondering if the car would benefit enough to justify the cost. At what lenght in the system, is the 3 inch justified? If you have 20 feet of straight piping, considering the heat at the start and temp decrease by the end, at what lenght is going down to 2.5 does not introduce negative effect on the system? Remember, the same mass of gas, cools down, reduces in volume and velocity, but not mass. Maybe going bigger though the system is better? Maybe going smaller, I don't know!
Hence, my question. Is there a benefit from making the last 1/3 of the system, specially the part with the most angles into it, a 3 inch setup like the first 2/3rds? That's what it comes down to.
Safety Car
Joined: Jan 2013
Posts: 4,138
Likes: 171
From: Missouri
St. Jude Donor '13-'14
Unless you're pushing very high HP (560+ at the wheels, and probably not even then), going from a 2.5" pipe to a 3" pipe will show no gains whatsoever, and depending on flow, may actually reduce performance if there is too little backpressure.
