1990 Chevy K1500 5.7 Exhaust Questions

[famouslee99gt]

I just bought a '90 Silverado K1500 with the 5.7 in it. I have to replace the motor but after that I want to do some exhaust on it. I was thinking of going true duals and straight out the back with some stainless angle cut tips. I had a friend that did that setup with glasspacks, and didn't like it at all because it sounded like crap when loaded. I was thinking of running two thrush welded mufflers, and was curious what others thought. I like the crackle sound and being loud, as I will not be driving the truck very much. I don't wanna run true duals with mufflers and it be real quiet. I want to do something cheap and be happy with it.

[VR021302]

Use the muffler that you have on ur 99, nothing wrong with knockoffs.

[66nova]

If you are planning on running "true duals" make sure you run some sort of crossover pipe (H or X). If you don't, you would be better off just running a single pipe or a single in dual out.

 

You will lose too much scavenging if you don't.

[famouslee99gt]

I've also thought about using the system on it now and removing the cat, and putting a knock-off single in-dual out muffler and run duals on it. I have also pondered running the dual exhaust that those older trucks did in which they both go out the same side.

[dlewis1111]

I had a 91 and ran headers into a performance Y-Pipe. I retained the 3" single exhaust up to the Flowmaster and it had dual 2.25" outputs that I ran out the back. For the cat - I ordered the intermediate pipe from Advance Auto parts and installed it where the cat normally would attach. It comes longer for use on all the different bed lengths and you trim to length. It was long enough to attach the muffler to. Sounded good and performed well too.

[famouslee99gt]

I'm going to run factory manifolds. I guess I need to get the motor in it first before I worry about the exhaust. I also thought about single exhaust w/o cat, back to a knock-off flowmaster and either duals out the back, duals out the side like stock, or just remove cat and leave it single back