exhausting question?

[cougarkiller]

Want to put a performance exhaust on my '85 350 swb 2wd gmc. I dont want annoying loud but I do want power and throaty sound. I'm thinking headers (obviously), x pipe, mufflers, etc. I'm a welder by trade so I think i'll just order some stainless tubing through the shop and take it to a muffler shop to have them bend the pipe then i'll tig weld it. My question is what headers long tube, short tube, or block huggers? Next question, 2.5" or 3" pipe? Next question, singe in dual out or dual single in single out mufflers? I dont want to cheap out but one muffler is half the price is than two are.  Next what would be a good muffler for this setup like I said I dont want to be obnoxiously loud. Thanks

[FlatBlack77]

I think long tube headers are the way to go. You can get em for about a hundred bucks from Summit.
http://store.summitracing.com/egnsearch.asp?N=700+4294923429+4294908216+4294925023+115+4294908213

3" will give more of a deeper tone than 2.5". It's up to you.

If you go with single in, dual outlet, you are going to have to go from two headers, into one pipe, into the muffler, then back out in two pipes.

As for mufflers there are many choices. Flowmasters, glasspacks, and so on.

[okuma]

but then again with 3" tubes you will loose low end power {torque}.  2 1/2" are most highly recommended.

[cougarkiller]

what about the x pipe how much hp can i expect i red at summit that this one x pipe would give 25 hp and i know that these numbers can be highly exagerated but....? can i expect 10-15?

[okuma]

i am not sure if you get any hp, I know H and X pipes will balance exhaust flows from bay1 and bay2. right side and left side of engine.

[VileZambonie]

yeah don't expect 25 HP! 2.5" is plenty big enough unless you are going big block. H pipe does the same as X pipe just less in the way of everything if you ask me. Don't skimp and use a pair of good flowmasters. Offset inlet center outlets work good for making the tails look wide.

[mikeith]

personally i dont care for flowmasters caus they have an annoying drone around 2.5-3k rpms due to them being chambered... magnaflows give a very nice sound and arent too loud... and no drone 

[cougarkiller]

Will i loose lots of ground clearence with the long tube headers? Also does anyone know a site where i can look up my engine casting numbers, im trying to figure out what year the motor is because i know its not an original. I think its maybe an early 90's.

[okuma]

I installd a pair of ceramic heher for a 1967 chevelle . they work awsome 3/4 lenght. great for air bags! you will have all clearance available.

[123 pugsy]

[quote author=cougarkiller  Also does anyone know a site where i can look up my engine casting numbers, im trying to figure out what year the motor is because i know its not an original. I think its maybe an early 90's.[/quote]

Here's a linl: http://mortec.com/

If you can't find what you need ,you can email him your serial number and you'll get a response. Good guy.

[Captkaos]

another place to look up engine numbers (which I use) is http://www.nastyz28.com

I wouldn't go larger than 2.5 on a SBC, and a H or X will quieten the exhaust down while helping.