[95opal]

Gor all those peeps who keep asking what exhaust? well heres a little chart to help you with your decision making.


The results in HP order:
1.Flowtech Warlock (open) 374.2 hp/ 333.1 tq
2.Bassani Real Street 373.7 hp/ 333.8 tq
3.Hooker Maxflow 373.5 hp/ 333 tq
4.Borla XS 373.3 hp/ 332.6 tq
5.Magnaflow 372.8 / 332.5 tq
6.MAC 372.3 hp / 331.5 tq
7.Flowtech Afterburner 372.3 hp/ 330.1 tq
8.Hooker Aerochamber 372.1 hp/ 330.4 tq
9.Bassani 372 hp/ 333.5 tq
10.Spintech 371.6 hp/ 332.2 tq
11.Edelbrock Performer RPM 370.9 hp / 331.3 tq
12.Borla XR1 370 hp/ 334 tq
13.Flowtech Terminator 369.5 hp / 331.3 tq
14.Dynomax Ultra Flo 369.4 / 333.2 tq
15.Flowmaster 369.4 hp / 331.8 tq
16.Flowtech Warlock 366.3 hp / 325.3 tq
17.No muffs 365.2 hp / 330.1 tq

Sound Off in Quietest to Loudest (Decibels):

1.Borla XS, 80db at idle, 90db at 2,000 rpm, 110db at WOT.
2.Hooker Maxflow, 80db at idle, 90db at 2,000 rpm, 120db at WOT.
3.Magnaflow, 82db at idle, 91 at 2,000 rpm, 114db at WOT.
4.Flowmaster, 82db at idle, 93 at 2,000 rpm, 115db at WOT.
5.Flowtech Warlock, 83db at idle, 92 at 2,000 rpm, 112db at WOT.
6.Dynomax UltraFlo, 83db at idle, 94 at 2,000 rpm, 113db at WOT.
7.Borla XR1, 83db at idle, 96db at 2,000 rpm, 118db at WOT.
8.Bassani Street, 83db at idle, 96db at 2,000 rpm, 120db at WOT.
9.Edelbrock RPM, 84db at idle, 93db at 2,000 rpm, 118db at WOT.
10.Bassani Real Street, 84db at idle, 96db at 2,000 rpm, MAX. (120+db).
11.Flowtech Afterburner, 86db at idle, 94db at 2,000 rpm, 115db at WOT.
12.Flowtech Terminator, 86db at idle, 94db at 2,000 rpm, 119db at WOT.
13.Hooker Aerochamber, 87db at idle, 94db at 2,000 rpm, 114db at WOT.
14.SpinTech, 87db at idle, 97db at 2,000 rpm, 116db at WOT.
15.MAC, 87db at idle, 98db at 2,000 rpm, 119db at WOT.
16.No Muffler, 91db at idle, 103db at 2,000 rpm, MAX. (120+db

[Tony_90fox]

good find! But questions will always be asked.

[Clean90GT]

No mufflers = loss in power? lol

Open exhaust will flow more = more power.

Looks like a marketing chart if you ask me.

[TENGRAM]

Originally Posted by Clean90GT No mufflers = loss in power? lol Open exhaust will flow more = more power. Looks like a marketing chart if you ask me.

open exhaust = loss in exhaust velocity, which can hurt power. backpressure is not a good thing but it can help by increasing velocity.

here's the whole dynochart:


while it is possible to tweak things to get the results you want from a dyno, i seriously doubt thats what they have done here.

[Clean90GT]

Originally Posted by TENGRAM Originally Posted by Clean90GT No mufflers = loss in power? lol Open exhaust will flow more = more power. Looks like a marketing chart if you ask me. open exhaust = loss in exhaust velocity, which can hurt power. backpressure is not a good thing but it can help by increasing velocity.

I knew someone would say back pressure. lol

http://www.uucmotorwerks.com/html_pr...torquemyth.htm

One more thing..... if mufflers can add power why do we see open header exhaust running so much in drag racing?

John Force better get some mufflers on his funny car.

Open = more power period. You can tune for the extra flow.

[TENGRAM]

Originally Posted by Clean90GT I knew someone would say back pressure. lol http://www.uucmotorwerks.com/html_pr...torquemyth.htm

lol all you want, i've studied the subject, which is why i put it the way i did: backpressure is not a good thing but it can help by increasing velocity.

Originally Posted by Clean90GT One more thing..... if mufflers can add power why do we see open header exhaust running so much in drag racing? John Force better get some mufflers on his funny car. Open = more power period. You can tune for the extra flow.

why then don't they run sewerpipe sized headers or for that matter no headers at all? its because they need velocity.

[Clean90GT]

Losing 10hp with no mufflers is BS.

Open exhaust will out flow a muffler system hands down.

[Clean90GT]

When you have open exhaust you tune the a/f for open exhaust. Just taking off mufflers can lose power if there isn't a proper a/f tune.

So basicly they pulled mufflers off and no tuning done for the extra flow.

[TENGRAM]

Originally Posted by Clean90GT Losing 10hp with no mufflers is BS. Open exhaust will out flow a muffler system hands down.

wrong. a lot more goes into exhaust than you think. velocity, reversion pulses, scavenging effect, etc. you need to do more reading before you make a definitive statement on this subject. you're contesting what a dynochart says...a dyno is the best tool available for proving power gains/losses, and is as accurate as is possible. but because you "know" something you must be right, huh?

[Clean90GT]

Originally Posted by TENGRAM Originally Posted by Clean90GT Losing 10hp with no mufflers is BS. Open exhaust will out flow a muffler system hands down. wrong. a lot more goes into exhaust than you think. velocity, reversion pulses, scavenging effect, etc. you need to do more reading before you make a definitive statement on this subject. you're contesting what a dynochart says...a dyno is the best tool available for proving power gains/losses, and is as accurate as is possible. but because you "know" something you must be right, huh?

I own a dyno foolie.

I said tuning is the key to open exhaust. Open up the exhaust then tune.

[TENGRAM]

Originally Posted by Clean90GT I own a dyno foolie.

why don't i believe you? oh thats right, probably because you use terms like "foolie"

[Clean90GT]

Originally Posted by TENGRAM Originally Posted by Clean90GT I own a dyno foolie. why don't i believe you? oh thats right, probably because you use terms like "foolie"

I really don't care if you believe me or not. But if you are in Chicago come by the shop any time.

If you think Rick Anderson was swapping out mufflers then tuning each one of those cars you are crazy. The amount of time it would of taken them to do that plus was he hot lapping the car? What are the temps in the dyno room after 20 pulls?

You can think what you want about mufflers... if you think that is the muffler bible then go for it. I'll tell you right now that a properly tuned car with open exhaust is going to out flow (your terms have increased "velocity")and will out perform a car with mufflers. Period.

Swap out a intake kit on a car and not tune for it and see how it runs.

Why do people run 3" exhaust if 2.5 has more "velocity? We should down size to 1" exhaust maybe... man that thing will have super velocity then.

[TENGRAM]

Originally Posted by Clean90GT You can think what you want about mufflers... if you think that is the muffler bible then go for it. I'll tell you right now that a properly tuned car with open exhaust is going to out flow (your terms have increased "velocity")and will out perform a car with mufflers. Period. Swap out a intake kit on a car and not tune for it and see how it runs. Why do people run 3" exhaust if 2.5 has more "velocity? We should down size to 1" exhaust maybe... man that thing will have super velocity then.

flow is not the same as velocity. if it were we'd all be putting box intakes on our stangs. people generally run 3" exhaust so they can tell all there friends about it but some people need 3" pipes because their motors are moving that much air, why don't they go 4"? because it hurts power. FYI, i just swapped a different intake onto mine, and because the EEC is adaptive, i've had zero problems and it makes noticeably more power than before.

[danthelion]

kudos, you've made the most intelligent posts on this topic. no lie!

Originally Posted by TENGRAM Originally Posted by Clean90GT You can think what you want about mufflers... if you think that is the muffler bible then go for it. I'll tell you right now that a properly tuned car with open exhaust is going to out flow (your terms have increased "velocity")and will out perform a car with mufflers. Period. Swap out a intake kit on a car and not tune for it and see how it runs. Why do people run 3" exhaust if 2.5 has more "velocity? We should down size to 1" exhaust maybe... man that thing will have super velocity then. flow is not the same as velocity. if it were we'd all be putting box intakes on our stangs. people generally run 3" exhaust so they can tell all there friends about it but some people need 3" pipes because their motors are moving that much air, why don't they go 4"? because it hurts power. FYI, i just swapped a different intake onto mine, and because the EEC is adaptive, i've had zero problems and it makes noticeably more power than before.

[SlowGTA]

"a dyno is the best tool available for proving power gains/losses,"

A dyno is very useful but is a tool, PERIOD.

Performance at your chosen form of racing is the best tool available for proving a performance increase.

On THAT engine combination the tested mufflers increased power.

If a muffler makes more power than an open exhaust on a dyno it is a good indication that the combination under test was over-scavenging at that RPM and load. The exhaust restriction reduced the problem that was hurting performance.

What those dyno pulls actually told you isn't that mufflers make power (blanket statement) but that THAT engine would be better off with a different cam (less exhaust duration or an earlier exhaust valve closing) to make maximum power.

Now if you have to run a muffler for noise control that might be the perfect cam for that combo because while it does over-scavenge with a free-flowing exhaust you had to use a muffler anyway.

Every engine is a big collection of compromises. A tuners job is to assemble those compromises in a way that best meets the needs of the intended application. What is the "right" choice for a pro mod car is rarely "right" for a 12Sec. bracket racer.

I love when people i destroy at the drag strip race after race start telling me my cam is too small, my headers are wrong and my injectors won't flow enough all because they've seen dyno numbers to "prove" it.

IMHO the bottom line is that if it wasn't my engine on that dyno it doesn't matter much.

[04musclestang]

Originally Posted by SlowGTA "a dyno is the best tool available for proving power gains/losses," A dyno is very useful but is a tool, PERIOD. Performance at your chosen form of racing is the best tool available for proving a performance increase. On THAT engine combination the tested mufflers increased power. If a muffler makes more power than an open exhaust on a dyno it is a good indication that the combination under test was over-scavenging at that RPM and load. The exhaust restriction reduced the problem that was hurting performance. What those dyno pulls actually told you isn't that mufflers make power (blanket statement) but that THAT engine would be better off with a different cam (less exhaust duration or an earlier exhaust valve closing) to make maximum power. Now if you have to run a muffler for noise control that might be the perfect cam for that combo because while it does over-scavenge with a free-flowing exhaust you had to use a muffler anyway. Every engine is a big collection of compromises. A tuners job is to assemble those compromises in a way that best meets the needs of the intended application. What is the "right" choice for a pro mod car is rarely "right" for a 12Sec. bracket racer. I love when people i destroy at the drag strip race after race start telling me my cam is too small, my headers are wrong and my injectors won't flow enough all because they've seen dyno numbers to "prove" it. IMHO the bottom line is that if it wasn't my engine on that dyno it doesn't matter much.

+1 he said it all right there

[punkafi888]

yall cant forget they are running 12.3:1 com ratio with nitometh and a s/c and spraying but loads of nos. not will you be doing that in your stang, maybe if you had 85k but not now. with that compression ratio they have to run with headers or they would loss aroud 70-120 hp.

drag tech student 101.

but back pressure is not nessisarily a bad thing, it does help creat some tq, but to much will cause you to loss hp.

the chart is right on. not a sales gimig.

[oasr87]

how about an exhaust for a 95' 3.8L that will be very quiet like 90 db at WOT?

yo quiero uno de esos

[El_Cangri]

d donde eres q hablas español? Should I keep my true dual exhaust or should I change them for a "h" or "x" pipe?

[BLACJAC]

i dont know about any other mustangs ,but the 05,06,07 gt develop more hp and torque with borla stingers or bassanni race axle backs the with no mufflerat all. mustang musclee compared 6 axlebacks and the two best were stingers and bassanni race ,both sets turned 10 rwhp and 12 pounds torque no muffler wqs good for 4 rwhp and 5 pounds of torque over the stock mufflers