[Fang16]

What's a good "muffler" for a streetable gasser? Running flowmaster 10's on 1 5/8" headers now but going to 2" headers. I've heard some bad commits on flowmasters. I'm guessing restrictive?

As to headers, I'm thinking tri-5 fenderwell gasser headers on a sbc 41 Willys?

[cobalt327]

I hope you're going to a BBC to match those 2" headers!

FM muffs have gotten a bad reputation. Whether it's deserved or not, I cannot personally say, having never run them back-to-back w/other muffs w/no other changes. If you believe the manufacturers of other mufflers, the FM's suck. There might be unbiased tests that have been done, I'd only use that, not ANY manufacturer's published numbers. Numbers can be made to look however you want them to look. Old saying: There are lies, damned lies, and there are statistics. Same thing holds true here IMO.

[F-BIRD'88]

On every car I have track tested that had flowmaster mufflers, it ran a whole lot faster and quicker when the
flowmaster mufflers were removed. A straight thru style muffler always works better.
EG: Magnaflow or DynoMax. Quieter too.
You have the mufflers. Go to the track and prove it to yourself.

I have a custom hand built one off modified tri flow (turbo mufflers) of my own design on my car.
The car runs slightly faster and quicker with the mufflers installed compared to open exhaust.
The difference is very very small. A lot quieter than flowmaster/no restriction.
Or if there is any restriction the engine don't know it.

Do a control tested A-B-A or B-A- B on-off-on test of at least 6 passes with good traction.

[joe_padavano]

Despite the obnoxious noise and drone, (no)Flowmasters consistently rank among the most restrictive mufflers in unbiased magazine tests.

Here's one:

Exhaust

[vinniekq2]

If its a "gasser" use thrush professionals.
2 inch headers on a small block requires adapters

[Fang16]

Originally Posted by vinniekq2

If its a "gasser" use thrush professionals.
2 inch headers on a small block requires adapters

Adapters? for what? Ones I've found haven't said anything about adpters.

[Fang16]

Originally Posted by vinniekq2

If its a "gasser" use thrush professionals.
2 inch headers on a small block requires adapters

Thrush doesn't list a thrush "professional" muffler. Do u mean thrush in general?

[vinniekq2]

2 inch primary pipe headers are too big to fit the stock exhaust bolt pattern on small block heads

Thrush professionals are a race muffler for race cars. Is this car a "gasser"

[Fang16]

Originally Posted by vinniekq2

2 inch primary pipe headers are too big to fit the stock exhaust bolt pattern on small block heads

Thrush professionals are a race muffler for race cars. Is this car a "gasser"

Guess I can contact Thrush and ask them about them as they're arn't shown on the site.

Learn something new everyday. Hate it when the parts sites don't mention that you'll need this or that to go along with the part.

Yeah, it's a streetdriven gasser (sbc 41 Willys) and I drive 85 miles or 130 miles to the track when I race.

Thanks for your reply.

[vinniekq2]

85-130 miles each way with a 4.88 rear gear and probably not legal muffler?

[F-BIRD'88]

Driving with a high rear gear ratio, which is music to the ears of some... is a lot less fatigue ing when the exhaust system is designed right.

You don't want a Red Neck exhaust system on a car you have to actually drive.

A good exhaust system that sounds good yet is not tiring need not be loud
or restrict power. Most of the stuff on the market is very poor including Flow master.

Make the exhaust exit out the back at the rear bumper. "gasser" or not.

The exhaust system can make or break the car.
A bad design will last forever cause the car will sit in the garage.

[kleen56]

This is another one of those controversial subjects of what's better. There is no definite answer. It's what you like and works for you. One person may run one brand and another swears by another. I'm not into racing my streetrod on a track or quarter mile strip, but I've run several mufflers experimenting. I would never buy Magnaflow again because they were expensive and didn't sound good. I've been running Flowmasters and the sound is nice, quiet at cruise speed and opens up when on the pedal. As for performance, really can't see a big difference with any of the brands I've tried particularly running a Small block. I guess some people feel the louder the exhaust, therefore the faster the car? Maybe there is a difference with the big blocks, a different story. Most of the gassers I've seen run glass packs! Just to put a mix into it... LOL..