Good day all,
Got a 1977 F150 4x4 with a 351M. I put a set of Sanderson headers on it that have a 3 inch exit that reduces down to 2.5ich into the exhaust. Need some advice on what mufflers you all would recommend? I have seen suggestions for Borla proxs but thay seem just a little to quiet. Flowmaster orignal 40 series also come up often.

Any suggestions?
Thanks in advance

 

I like my Turbo Mufflers. Mellow and soothing.

1986, saw the truck on a closed car lot one Wednesday night, called next day,, they were asking 5,500, I said foolishly "Five and I'll come get it Friday". "OK" he said. Friday night coming home on new interstate, 42 miles, two Cherrybombs hanging under frame rails, pipes out in front of rear tires. Awful coming up North Mountain, wife behind in her Subaru, said it was "LOUD" It sat in my driveway until Dale could pull that mess off and do a proper system out the rear with lifetime warrantied turbo mufflers up between rails.
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I don’t know your tolerance level but chambered mufflers (flowmaster) drone on most set-ups. My go-to mufflers are turbo type design. For old trucks/cars etc I normally install dynomax turbo’s.

 

I currently have a 2.5" side exit exhaust with Thrush turbo muffler on my truck with a 400 in it. Its not the best sounding, but not horrible. I cant imagine the numerous exhaust leaks I have are helping the sound. However I do like that its quiet enough to keep my neighbors happy, but when I stand on the gas you know I'm there.

 

I just put on some flowmaster fx and really like the mellow sound

 

I have headers and 48" glass packs on the 428 CJ in my high boy. I did it mainly because of how hard it is to fit mufflers on a high boy but in the end I love the sound. I've actually had guys come up and ask what exhaust system I got to make it sound so good.

 

I run Flowmaster 50 series all the way out the back with headers and a cross over. I don't usually like Flowmaster sound but these are just right. No drone, pleasant sound at idle and cruise, gets quite a bit louder when you nail it.

 

I have turbo-type mufflers on my '73. Good sound, not obnoxiously loud.

 

At one time I had glass packs but they had so much drone they rattled the screws out of the interior trim. Ovnoxious on the highway. There are different brands of course.

 

x2 on these. They are a good balance on good tone and loudness. These are not the typical chambered design that Flowmaster normally uses, so no droning that I have noticed. They are pretty much the same design as a MagnaFlow (another good choice), but these were less expensive.

 

My opinion, worth nothing but what you pay for it I'm a fan of the old school glass packs, just put one on my 2000 Excursion w/5.4, the PO had put a flowmaster 10 on it single in DO, underneath the 3rd row, TERRIBLE sound, terrible drone, took it to muffler shop in Fresburg, 18" 2.5" glasspack SI/SO exit behind rear tire, LOVE it! Mellow yet has a little bark when up in the R's when I had it in the shop to re-gear to 4.88's Zach and the guys were all checking her out, saying they hadn't seen a glasspack in eons, 2 of the young guys had never seen or heard one, but it got lots of compliments from them, and wasn't pricey!

I have yet to like any of the flowmasters, every one I've heard or ridden in all have a drone at some level. On 2 of my 77's, both 351Measly's, I have resonators, short, about 15" or so, from newer Ford trucks and that is it, they both sound really good, IMO, and have had many others ask about them. They were free and basically brand new from a buddy's scrap pile. My 66 F100 inline 300/6 has a 12" gp, nice rumble for a 6...

But alas, exhaust sound is very subjective, and some like a nasty raspy flowmaster sound, me, not a fan... and I have found, muffler placement also makes a difference... I like the cackle of having the muffler closer to the manifold and the long pipe after, wish I could find an old used exhaust pipe bender to play with on my old trucks and "tune" them so to say

 

A lot of drone can be killed with 8 or 10 pounds weight clamped to the head pipe ahead of those FMs & etc. Why Ford attached weights to like Crown Vics, etc.



Made up of two of those C-V weights which are like concrete filled pipe and a piece of angle, just clamped on .... worked wonders on my '07.



I had already by then put a28" long 3" ID stainless steel Cherrybomb ahead of the little chambered muffler as a resonator hope, it quieted it some but it didn't kill the drone at 65.

 

Try the Pypes Turbo Pro. It's their quietest muffler, but I still think it's quite loud at idle. It shakes the glasses in the cabinet in the house when I fire the truck up in the garage. Great idle sound with the old school carb'ed, big cube engine gurgle, but it isn't obnoxious at cruising speeds and that's with pre-axle turndowns. I'm running a 445FE with a somewhat aggressive cam so I can't testify to how it will sound on a 351 with a stock cam, but you can go up to the Race Pro which is the next loudest muffler they sell if the Turbo Pro isn't to your liking.

 

Also, if you end up having rasp or drone a resonator can cure a lot of that. SLP sells one that was used a lot on the old F-body Camaros and Firebirds. I can personally attest to their effectiveness.

 

I only have a little old 300 six with the EFI manifolds, mini headers, into a full 94 F150 system, less cat, on my 81 F100 but replaced the stock replacement muffler with a Thrush welded replacement muffler.
Gives a nice rumble at idle and when you bring the RPM up not loaded. Have not had anyone do a "drive by" in my truck when I have not been in it.

I have had another six with long tube headers into a Y pipe a small turbo muffler and tail pipe behind tire, Jeep type truck, and it sounded nice at idle but get on it under load you could hear it coming.
A v8 in a blazer, long tube headers pipe to 18" turbo mufflers and tail pipes behind tires and like the above you could hear it coming when under load.
Then again I was a lot younger so it was cool dont know if I would like either not in my 60's?
Dave ----