[MSilva]

With all the tracks starting to mandate mufflers on race day, I was wondering what everyone is using? Also, what kind of performance or ET loss did you get by adding the mufflers?

[MSilva]

With all the tracks starting to mandate mufflers on race day, I was wondering what everyone is using? Also, what kind of performance or ET loss did you get by adding the mufflers?

[Goatman]

I use Race Magnums. Not sure they'll pass noise tech, never ran the car without them. I am a believer in muffler technology and I also believe that you can get a car to run just as fast with mufflers as without if you do your homework.

10.62 @ 128 3500lbs

[jack gaydosh]

I have used Vortec cone insert mufflers for three years. They have passed nhra tech at national and divisional events. They had no problem passing the 95 decibel ruleas measured on the "a" scale froma distance of 50 feet,at a right angle to the vehicle,with the vehicle at no-load rpm of 3500. Many other good mufflers out their. Good luck to everybody and have a safe season jack gaydosh

[Torment]

I've run the same back to back with Race Magnums-very loud.

[Jack Ferris]

Soo, with the race Magnum are you bolting them directly to the header or are you using a length of pipe and mounting them to that?

[Goatman]

I have an 18", 3.5" diameter collector that opens up to 4". The Race Magnum is welded to that, and then I have a 4" turndown welded to the end.

[PONTIAC DUDE]

I run 2 Chamber 3.5" Flowmasters. They are really freakin loud, especially when I have the 3" tailpipes hooked up.. LOL
A lot of the other car mags do muffler test and use ET and DB tests. Check them out. Also depends on your current ET's as some mufflers will offer no power loss/super quiet at 12 sec, but really restrict in the 8/9's/10's.

[Torment]

In my experience you do not want to bolt them directly to the collector. I did that and chased a huge stumble when going to WOT for the better part of day before I realized it was the friggin' mufflers [img]/infopop/emoticons/icon_smile.gif[/img] Put 2 feet of 3" pipe off the collector in front of them and no problems. I have them turned out to exit in front of the rear wheels. Blows the dust off the street for ya [img]/infopop/emoticons/icon_wink.gif[/img]

[ March 24, 2002: Message edited by: Torment ]</p>

[tempest455]

We made some back to back runs on a mid 10 second car last season with and without the mufflers. Like Pontiac Dude, this car also had 3.5" 2 chamber Flowmasters but with no tail pipes. The Flowmasters were side in straight out. Apparently, the side in are more restrictive. We made 4-5 runs with the exhaust closed and 2-3 open. The car only picked up .07. Hardly worth the effort on this car. Possibly jetting up may have helped but we just wanted to see what the change was open. IMHO, it actually sounded better with the mufflers on!

[MACNICOLRACING]

When I changed my heads the car picked up over 1/2 sec. I then put on 3.5 race Flowmasters(offset due to the chassis) the car slowed down .2 tenths from open headers. I now run a set of Dynomax bullets with a set of Borla XR1's(4") the car is extreamly quiet. At the time it ran 10.42 open headers and 10.41 with the Dynomax/Borla combo(40lbs. in weight?). The bullets act as a resonator and really help reduce the noise.

[yournose]

I use THRUSH glass packs, 32" long. Could not be happier.

[yournose]

I use THRUSH glass packs, 32" long. Could not be happier. Straight through.......in-out, history.

[PONTIAC DUDE]

A buddy of mine runs the Dyno max mufflers also and they are a lot quieter and he loves em. Fit's in a tighter place too.
David, you know Cecil with my ole engine, and his car ran 10.0's with them weighing over 3500 lbs. Actually street legal and quiet too.