Kind of related to my Premium Fuel question, I would like to put a Turbo Muffler on my '93 4.9 V-8.
I would like to let the engine breathe more and try to boost the milege a little better, but also would like to have a little more sound. There are times that I can't hear the engine run, especailly at an idle. I know that there are many Cadillac owners out there that just love a quiet car, but I could sure use some sound.
My question is, I want to make sure that there are no drawbacks on putting a Turbo Muffler on a 4.9.
Don't know about drawbacks, but the 4.x series engines sound great with a performance muffler. I wouldn't expect more than about a 3-5hp gain though unless you change the catalytic converter and exhaust pipe diameter. At least it will sound awesome.
There is a thread in the 4.1/4.5/4.9 engine forum that discusses performance upgrades/enhancements. Some very valuable stuff in those posts, including info about the exhaust. Search it out, it states the engine performance and fuel economy both benefit (at least a bit) by upgrading from the stock muffler.
Automobile(s): '91 Sedan DeVille Silhouette Special
High Point, NC
Re: Turbo Muffler on a 4.9
Turbo mufflers sound pretty good on a 4.9, and there aren't any drawbacks. For me, I went with a fiberglass filled "import style" muffler.
That's the style I have, not the same muffler. It sounds absolutely amazing - I have everyone from Mustang, Camaro, and Corvette owners complimenting me, all the way up to guys with CLK55 AMG's and Porsche Carrera 4S's saying my car sounds good. I recommend the OTTO Racing brand, however there are thousands of brands of this type of muffler to choose from so shop around.
As far as performance gains, you'll see more than 3-5hp from a muffler upgrade on a 4.9 car. It's a V8, not a 4 banger - 4 bangers can see 3-5hp from a muffler upgrade. I'd guesstimate around 12hp if I had to - It's a very noticeable difference. Upgrading to bigger pipes is probably not needed for most people - The stock is 2.75" mandrel bent, more than enough for an otherwise stock 4.9, however if you plan to do any major mods you'll find that the 2.75" pipe is a LITTLE too small for the motor.
heres mine, its a 4.9 with a flowmaster 80 muffler with dual camaro tips
That's awesome! I'm running a similar muffler (80 series knockoff) and the same tips on my '92 ETC. I can't get over how good the 4.9 sounds with a chambered muffler. I swear it sounds better than the lt1 in my old z28. I can't wait to see how it sounds with a high flow cat.
See here's what I'd like to know. I want dual outlets on my exhaust (91 Seville 4.9) and I have no cat. Will the shop put the muffler where the cat used to be to run the proper pipes?
It depends on the shop. Some don't care, and if the converter is already off, they'll do anything you want. Some will only work on the area behind where the cat is supposed to be if it isn't there and some are so gun shy about fines that they won't touch one without a cat unless it's to put a new one on.
I've had the best luck with just asking before hand. If they say no, then try a different shop. You'll find one eventually that will do it.