Better than stock muffler options?

[Dave in Texas]

Is there a muffler that flows better than a stock unit? I don't want a loud muffler, afterall it's a Cadillac, but a little more 'umph' in my new 4.1L would be nice. Rock has 4 Walker models, but I don't know which does what? Thanks for any advice

[Cadillac Jim]

It depends on what you mean by "better." The OEM mufflers are very quiet, particularly the DeVille mufflers, and all are stainless steel that will last the lifetime of the car, barring extreme conditions such as long-term soaking in salt mush as can be seen in cars parked outside in freezing weather in the Salt Belt. I would recommend that you replace your mufflers with stainless steel regardless of which muffler that you select.

I don't know anything about the 4.1 in the Deville; I hope what I have here is useful and applicable. My experience is with the Northstar, model year 1997, Touring package (300 hp). I was rear-ended in September 2006, the main damage being the exhaust system behind the rear Y was taken out. What I learned includes

• The dual tips come with the stock mufflers and are not available separately. My tips were destroyed on the left side.
• The stock mufflers aren't symmetrical; the right side comes with the rear Y, the right muffler, and the right tips, and the left side comes with just the muffler and the tips. Both together is everything from the rear Y back except the hangars.
• The stock tips are stainless steel and chrome and can be cleaned up and re-used. I ended up with the tips from a 1994 STS, cut off mufflers taken from a salvage yard.
• Aftermarket mufflers are available from a variety of vendors, the most notable being Borla.
• Some muffler shops use welds that will rust; you can spot these as those whose primary clientele is trucks and SUVs. Some muffler shops use stainless steel welds. A stainless steel system welded with steel rods will rust apart. Ask before you let them work on your car.
• Aftermarket mufflers come in Turbo, Super Turbo, and Performance lines. Most people like the Super Turbo mufflers.

Turbo and Super Turbo mufflers have a vented or perforated S-pipe inside the muffler but are otherwise straight through. Vents in the S-pipe and take away any harshness of the sound and can sound almost stock in highway cruise. The difference between Turbo and Super Turbo is the vents and packing and thus the exhaust note; I don't expect that there will be any difference in gas mileage or performance and both will give a slight improvement over stock mufflers. Performance mufflers are straight-through with vents; I could see two inches of daylight through mine when I opened the box. But, the Northstar exhaust system is inherently not too noisy, even with no mufflers at all. My wife likes my exhaust sound, but she has never heard it wide open at high RPM.

If you are really interested in more from your Cadillac, you might look into a 4.5 (180 hp) or 4.9 (200 hp) to replace your 4.1. This might be more than a simple transplant because of the digital integration of the modules, so let's see what others here have to say about that.

[Dave in Texas]

Thanks for the info Jim. My 'new' 4.1L engine is a GM-factory rebuild that was stored for some years. It's a 0-miles/hours engine, until I pressure-oil it and then start it. The exhaust system is a one muffler type w/2" pipe. I'm thinking the OEM muffler is prolly somewhat restrictive, but I'm guessing about that.

[Ed Hall]

Dave,

Here are some photos of my setup (1988 Eldorado). I used a Flowmaster Deltaflow model 60 muffler. It was the quietest muffler offered by Flowmaster. I simply sawed off the old muffler and used clamps and adapters to attach the new muffler. The new muffler is much better construction than the original. I noticed no difference in interior noise compared to stock however, it does emit a more athoritative growl under full throttle now. It probably did increase power a bit but it's not really that noticeable since these engines are not heavy breathers. If you want a little extra power out of that 4.1, you might try advancing the timing 2 or 3 degrees.

[Cadillac Jim]

Clamps are fine, and were used by OEM for many years. I would suggest that you get stainless steel mufflers AND stainless steel clamps. Flowmaster didn't offer stainless steel when I bought mine, but they do now. Flowmaster has a unique (patented?) low-restriction baffle that offers the same low restriction as turbo mufflers but with a uniquely pleasant exhaust note.

[Ed Hall]

My setup has served me well for the last 7 years. When I bought my Flowmaster, stainless was not offered at the time but since I live in the west coast where salt is not used, rust is not an issue. The original muffler on my 88 Eldorado appeared to be constructed out of thin galvanized sheet metal. It looked literally brand new when I sawed it off.

[Dave in Texas]

I won't be buying a SS muffler. The regular almzd-steel will do fine, since it will outlast me. I've been looking at the Flowmaster brand, but can not figure out what the differences in the 'series' are? They go from 10 series to 80, but I can't discern the differences......

[Ed Hall]

You want to visit the following site.

http://www.flowmastermufflers.com/mufflers.html

Next to each muffler listed is the type of car the muffler is recommended for, noise level bar chart, picture of the muffler and a description. In general, if you want a quiet muffler, go for the 3 chamber Delta Flow type.

Based on your description of wanting a quiet muffler, the 50 Series Delta Flow - Three Chamber Mufflers fits that description. That's what I've got on my 88 Eldorado.

[Dave in Texas]

geez, I'm losin' it. I replied, but forgot to actually hit the button....

Anyway, thanks Ed for that link. That is exactly what I was trying to find. Not a cheap unit are they?

[SPreston2001]

If your asking if Flowmasters are a cheap brand as in quality no. Flowmasters are some of the best mufflers out there. Very unique performance and sound. If you were referring to price, well their not the cheapest muffler, but definetely not the most expensive. Alot of times you can find them on Ebay for alot less than retail. Another good exhaust setup is made by Corsa. I eventually want to install a complete Corsa exhaust kit on my STS with high flow cats, but with Xmas right around the corner I cant afford to drop $1100 bucks on my toy lol!

[Dave in Texas]

"Not a cheap unit are they?"

Excuse me for the word. I was referring to cost. Shoulda used 'inexpensive'. I know the brand, just haven't bought one previously.