Newbie here.

I am rebuilding my '67 coupe with dual exhaust and was wondering if I should go with the regular FlowM 40 or the FlowM Delta 40. What is everybody running out there?

What kind of things should I look for? Is Stainless Steel a good option?

What can I expect to pay??

Thanks in advance.

 

Its hard to answer your question without knowing what you perfer, but here goes.

I have the Flowmaster 40 on mine and love it. The delta 40 will be a tad quieter outside and less interior noise. The 50 delta will be significantly less of both. Alot of guys like the 50 delta for good sound with out being loud. It basically depends how you want your car to sound. I don't think the regular 40 is available in stainless. The 50 series is now I think. Stainless is better, but it cost more, but will last a long time.

You can get a pair of Flowmasters from performancecurve or performancepeddler on ebay for a good price which is cheaper than just about anywhere else I have found.

If you need a whole new exhaust system that could be a few hundred bucks maybe even 400 from the manifolds back.

I would go with 2.25 pipe and mufflers for a stock or near stock motor. If its modified significantly then 2.5 inch for all.

 

Go with the original 40 it is the best, comes in 2.25 inches and above, the delta 40 starts at 2.00 inches and above. Super 44 and super 40 are also good mufflers, louder than the delta 40. They claim super 44 is the most aggressive sounding, but I think the original 40 is better by far. Expect to pay $200 for the pair of mufflers.

 

Based on my experience with my 1994 GT, if you want to hear your car loudly then you will want something more than the delta 50s. They sound really mean, have a decent idle sound level, and get quite a bit louder in the higher RPMs. There is no "droning" that I notice.

However, with my 94 I get things like the catalytic converters which lower the sound level of the exhaust, so the 50s may be much louder in a classic Mustang.

I'd go with the original 40 or the delta 40, I would assume the delta 40 would be more of a low grumble compared the the original 40.

Don't forget to check out Flowmaster's brochure if you haven't, it shows sound level comparison and gives you an idea of what to expect.

 

I got a pair of original 40 series from performance curve for less than 100 bucks shipped. Both ebay sellers I mentioned are about the same.

 

the louder the better