Quite Performance Exaust ? which one is the best.

[Doc Voodoo]

I want a Muffler that sounds Great at the Tail Pipe but is as quit as you can get in the interior of the Car. Mind you its a convertible which has alot of road noise as it is. I am running JBA headers , Duel GT exaust , 270 roller cam , roller rockers , edlebrock intake , holley DP 600 and the heads have been worked with over sized Valves .

I want to be able to talk to my wife and listen to the radio with out it being blasting at least with the top up. The wind with the top down is a diffrent story. I also want it to still have that nice thump to the exaust at the very back of the Car.

I dont want much

 

[NorCal66]

Well...that's kind of a toughy, I don't know how big the "quiet muffler aftermarket" is, but you never really hear about the quiet ones, it's always the ear-bleeding ones that get the attention. Maybe look into Flowmaster Delta Flows? They're susposed to be quietER and bassy, although I've never heard them myself.

 

[slick761]

aww its totally do-able. I have all thick guage tubing after the headers and dr gas spin tech mufflers. Sounds great outside and is nice and quiet in the cabin (as long as you have tail pipes after the mufflers, turndowns hurt my ears). when you get on it it sounds a lot like a 95 cobra but louder! Ill try to post a soundbite, not great quality but youll get the idea of what it is from the outside

 

[Ozsum67]

quite-an adverb
quit-to stop

 

[351c-ya]

I remembered this being posted on VMF a few months ago, so I cut and pasted. Hope this helps:

This test was performed by 5.0 Mustang & Super Fords Magazine, December 2002 issue (page 55) on a '90 Mustang LX coupe with 370hp and 11 second potential. 66 pulls were made for this comparison:

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).

Lance

 

[65fastback2+2]

go to meineke and the their "house turbos" i just had em put on my 67 coupe, sounds nice at idle and quiet on the highway. I actually was upset they werent loud. They still give you the nice rumble though, but they are very quiet.

 

[65shlbycln]

Maybe look into Flowmaster Delta Flows? They're susposed to be quietER and bassy, although I've never heard them myself.

No way! I have 40 series Delta Flows, and they drone like no tomorrow. It drives you insane if you're doing alot of stop and go stuff. It only quiets down when you're on the freeway if you're driving in the upper RPMS.

I say just go for some turbo mufflers. They'll be the quietest, and will flow decently well.

 

[brianj5600]

Dynomax super turbo's are another to consider. I have had them on a couple of cars and like the balance of hp and sound. I hope I don't get dinged by the grammar police, j/k.

 

[one2gamble]

magnaflows

 

[slick761]

are you sure those decibel readings were taken in the cab?

 

[STSFCTN67]

I went with delta flo 50's- perfect sound and only loud when I want it to be.

 

[Toughlou]

so according to that test you only get a 3 hp increase on the best muffler and a loss of hp in a few others? wow.

 

[one2gamble]

its just a muffler

 

[351c-ya]

so according to that test you only get a 3 hp increase on the best muffler and a loss of hp in a few others? wow.

374.2 - 365.2 = 9 hp at the wheels