How To Cure a "Rappy" Exaust?

AdamR said
A cross over pipe will help. X or H.

I'm trying to avoid that right now due to the money situation. You're right though, a crossover should give low end torque a boost which would be a good thing for this build and will most likely knock the rap out.

memike said
Glad to see and hear you are moving forward ramcharger.
If anyone can fab something, I have seen your handy work and I bet you will come up with something great brother :cheers:

I agree a pair of cannons will do the trick.8)

Thanks for the vote of confidence Mike! We'll see if this works or not. Hopefully it won't bring the rap up from "tommy gun" to "automatic cannon" status! Might be an interesting experiment.

grimreaper said
My pickup had that annoying rap to it too. 2-1/2 pipe turned out behind the rear wheels. Tried several different mufflers, glasspacks and several other things but only got the thing to sound decent when I installed a crossover pipe. I was reluctant for clearance issues too. You can fit one up nice and tight if you plan the routing. Mine ran exactly in front of the transfer case skid plate. Never scraped the crossover once through a lot of serious 4-wheelin' in the mountains. (which did require the Warn winch on several occasions) Sounded great with the crossover and magnaflows. Nice deep purr that turned to a deeper growl on acceleration...none of that overly rich Chebby rappin'........

Thanks Reaper,

Once I do a complete exhaust on this, I'll take a peak at how much room I have to add a crossover. Not only am I concerned about clearance, but ease of maintenance too. I don't want to have to cut the exhaust if I need to drop the trans/T-case. Maybe a removable crossover is in my future plans?

66340SEDAN said
Flowmasters baby! I have 2 1/2 pipes with flowmasters, wouldn't have it any other way!! Here are a couple sound bytes with the Flowmaster muffs and 340 power. 8)

Thanks 66340! I saw your previous posts this past week and your ride sounds great! I think that it's the length of the entire system in conjuction with the restrictive muffler shop bends that's making it "Rappy" rather than the mufflers.

Bigmacdak said
I agree with 66340SEDAN. I would put a set of 50 series delta flow flowmasters on it & drive. The 50 series is a quieter muff. than the 40 series, but its not too quiet. & like Adam said, a good H or X pipe will compliment it as well. Flowmaster all the way!

I'm starting to agree that a crossover would do the trick, lol! Just can't do it right now is all. A complete re-vamp will be in the works to compliment the new engine and I will most likely go with the FM 50 series when the time comes.

65Val said
Funny how it's mostly trucks that do this. I had a F*rd pickup with a warm 466 in it that did the very same thing. I hated the sound. The only thing that cured it was a cross-over pipe in the headpipes. In my case it was a Dr. Gas X-pipe. I was running Dynomax Super-Turbo's at the time. It made the same noise in town, but, curiously, at hi-way speeds, you could hardly hear the engine,,, till you hammered it to pass someone. It actually seemed like it increased the torque down low.

It's got to be the length in combo with crappy restrictive bends and a higher compression engine that's creating this sound. I was under the truck last night (and most of the day, lol!) and noticed that the bends cut the diameter almost in half. This is the same exhaust I was using previously with a stock compression engine and a XE262 cam and noticed no rappyness.

When the time comes, I think a 3" exhaust in combo with the FM 50 series mufflers and some type of removable crossover will be key in getting the sound and performance I want.

Thanks again everyone for all of your ideas.