Muffler/Exhaust Questions

[byates2]

Years and years into my 67 C10 project and I am finally within sight of seeing my wonderful truck run again since about 10 years.

My newest project and focus is now the exhaust system. The motor has been beefed up and I want a performance minded exhaust system to help that sucker breathe. I have Hooker headers on there and I was thinking like 2.5 inch pipe with some good performance mufflers, maybe like Cherry Bomb glasspacks or magnaflow or whatever.

The engine has been bored to I think 388, stroker, racing cam, so its got some muscles.

What have some of you guys done to yours? What do you guys suggest?

[DBK81]

I've always loved the low rumble of 3" strait pipes!

[tommy3horse]

Hi,

2 1/2' diameter pipes, true duals, Flowmasters and a bologna-cut exit in front of the rear tires. Sounds awesome. The truck came with Flowmaster "Sportsman" racing mufflers, they were like running open headers....way too loud.

Tom

[byates2]

I def like the idea of a low rumble. I want some sound but not the get pulled over type sound.

[Supergas]

I just bought the Magnaflow complete kit # 16643 for my 67 SWB..

It includes inlet pipes, tru X assy., Mid Pipes, 2 mufflers, 2 tail pipes, all SS and all in one box.. 2.5" all the way out..

Great deal on the internet Sunday, 20% off best price plus free shipping..

Supergas

[Mike C]

Same thing I've been preaching for 15 years. DynoMax Hemi Turbos. All the flow you could need for 400 whp and no drone or obnoxious noises.

[skylerlt]

Originally Posted by Supergas

I just bought the Magnaflow complete kit # 16643 for my 67 SWB..

It includes inlet pipes, tru X assy., Mid Pipes, 2 mufflers, 2 tail pipes, all SS and all in one box.. 2.5" all the way out..

Great deal on the internet Sunday, 20% off best price plus free shipping..

Supergas

Can you post up installed pics when you get it all on? I've been looking at that kit, but am curious about how much work it would be to route it all up inside the frame rails, and through the cross members. I'm assuming all of the stuff past the trailing arm crossmember wouldn't change much. I guess I'm just curious as to what the kit looks like installed.

[Supergas]

It will be a while before I install the exhaust..
But I'll post pics when it is done..

SG

[DarkFlounder]

I'm also planning on a new exhaust for my 72 K2500. Plan on keeping the ram horns. 2 1/2" dual pipes with an H crossover and Flowmaster 40s. Haven't decided on a dump location (front of rear tires, behind rear tires out sides, straight out back). Hoping to do stainless steel complete.

[piecesparts]

Let me tell you a story about a truck.

I put together my 84 SWB GMC a long time ago and like you I put on a set of long tube headers and wanted to go dual exhaust. I had installed a 383 stroker engine and wanted to do the exhaust right. I called several sources, being Flowmaster and Magnaflow. The feedback that I got was interesting. They both gave reasons for NOT going to a 3" exhaust, which fit into what size engine and what type of driving that I was going to be doing. (383 stroker engine, 700 R4 tranny, 3.73 gears, and highway driving) The 3" piping would be great, IF I was going to be running a large bore engine (big block) and was going to have a lot RPMs involved. Otherwise the use of 3" piping was detrimental to efficient operation of your engine. You want several things to happen when you have an exhaust system connected to an engine. First, you want the exhaust to work with your engine and not against it. That means the exhaust gases need to be removed, so as not to restrict the removal of gases from the cylinders. So, if your exhasut piping is too large, then the gases get "Lazy" and will not create a vacuum effect to pull the cylinders clean, so that a fresh charge of fuel laden air will enter the cylinder. If they are the right size, then the gases will shrink as they cool and this will cause a vacuum on the cylinders and sweep them clear. If the piping is too small, then the gasses still cool, but cannot be removed efficiently.

You will want a 2 1/2" exhaust system for your truck, if you run duals and the choice of muffler is up to you, but I finally settled on Magnaflow mufflers after having several Flowmaster muffler failures in the following years after the build. I have found that the Magnaflows give a low rumble while drivng slow and a loud respnse under heavy throttle. If you run a single exhaust, then a 3" pipe will work for that setup.

My 84 truck is still on the road, with another engine in it and it is no slouch in a run and I can pull down some decent gas mileage with the setup that I have.