hutchman
Member
I've searched until my eys are bleeding but I cannot find what I want. It seems there was a thread several months ago by a member who put a DIY exhaust system together for his truck....and I cannot find it.
It seemed he or she, started with replacement of the merge and muffler. He also did a resonator delete. Again, I just can't find it.
So, I'm thinking that I'll start with a 2.5 in and 3.5 our merge back to an aftermarket muffler. I'll use the factory over axle pipe, which I'll cut the resonator off and extend to bring the outlet to the side of the bed.
My new truck is a 2016 PW.
So my questions are...
1. Are the factory pipes prior to the merge in fact, 2.5"?
2. Curious about specific muffler recommendations from those who have changed them.
Kind of anxious to order some parts and get started.
And FWIW, some interesting information:
"Easy Way To Estimate: Your intake system needs to flow 1.5 CFM per engine horsepower, and your exhaust system needs to flow 2.2 CFM per engine horsepower.
Good Way To Estimate: Take engine RPM x engine displacement, then divide by two. This is the intake volume. Use this same volume of air for the exhaust system, but then correct for thermal expansion (you need to know exhaust temps to figure things out).
Exhaust Pipe Size Estimate: A good section of straight pipe will flow about 115 CFM per square inch of area. Here’s a quick table that shows how many CFM each common pipe size will flow, as well as the estimated max horsepower for each pipe size:
Pipe Diameter, Pipe area, Total CFM (est.), Max HP Per Pipe, Max HP For A Dual Pipe System
1 1/2 1.48 171 78 155
1 5/8 1.77 203 92 185
1 3/4 2.07 239 108 217
2 2.76 318 144 289
2 1/4 3.55 408 185 371
2 1/2 4.43 509 232 463
2 3/4 5.41 622 283 566
3 6.49 747 339 679
3 1/4 7.67 882 401 802
3 1/2 8.95 1029 468 935
NOTE: These numbers are just estimates. All pipes are assumed to be 16 gauge steel.
The table above is probably over-estimating pipe size, but you can see that a 400 hp vehicle with a dual exhaust system only needs 2 1/4 – 2 1/2 inch pipes. Anything larger is overkill."
It also appears that 3.5" is sized correctly for the factory hp rating.
It seemed he or she, started with replacement of the merge and muffler. He also did a resonator delete. Again, I just can't find it.
So, I'm thinking that I'll start with a 2.5 in and 3.5 our merge back to an aftermarket muffler. I'll use the factory over axle pipe, which I'll cut the resonator off and extend to bring the outlet to the side of the bed.
My new truck is a 2016 PW.
So my questions are...
1. Are the factory pipes prior to the merge in fact, 2.5"?
2. Curious about specific muffler recommendations from those who have changed them.
Kind of anxious to order some parts and get started.
And FWIW, some interesting information:
"Easy Way To Estimate: Your intake system needs to flow 1.5 CFM per engine horsepower, and your exhaust system needs to flow 2.2 CFM per engine horsepower.
Good Way To Estimate: Take engine RPM x engine displacement, then divide by two. This is the intake volume. Use this same volume of air for the exhaust system, but then correct for thermal expansion (you need to know exhaust temps to figure things out).
Exhaust Pipe Size Estimate: A good section of straight pipe will flow about 115 CFM per square inch of area. Here’s a quick table that shows how many CFM each common pipe size will flow, as well as the estimated max horsepower for each pipe size:
Pipe Diameter, Pipe area, Total CFM (est.), Max HP Per Pipe, Max HP For A Dual Pipe System
1 1/2 1.48 171 78 155
1 5/8 1.77 203 92 185
1 3/4 2.07 239 108 217
2 2.76 318 144 289
2 1/4 3.55 408 185 371
2 1/2 4.43 509 232 463
2 3/4 5.41 622 283 566
3 6.49 747 339 679
3 1/4 7.67 882 401 802
3 1/2 8.95 1029 468 935
NOTE: These numbers are just estimates. All pipes are assumed to be 16 gauge steel.
The table above is probably over-estimating pipe size, but you can see that a 400 hp vehicle with a dual exhaust system only needs 2 1/4 – 2 1/2 inch pipes. Anything larger is overkill."
It also appears that 3.5" is sized correctly for the factory hp rating.
