long tubes with flowmaster single chambers

**treefiddy** · 03-27-2012, 08:34 AM

hey guys, new here and just wanting some opinions on an exhaust set-up. i've got a '93 k1500 that i want to run true duals on. i'm thinking about either running true duals out the back with a set of 10 series single chamber flowmasters, or the same set-up but with a set of hooker long tube headers(2462HKR), or flowtech mid-lengths(11508FLT). i've run headers on lsx motors before and never had a problem but i've read with these older motors they can be a head ache with getting them to seal properly and clearance problems with 4x4's, etc. how much do yal think they'll actually change the sound? thanks.

**1988 GMC 355** · 03-27-2012, 03:19 PM

HEaders are awesome on the TBI trucks, a great upgrade, my Hedmans and Hookers both fit great and the Flowtechs do too, just use Fel Pro exhaust manifold gaskets and not the indiviual ones.

**treefiddy** · 04-09-2012, 07:28 AM

ok great. i think i'm gonna get a set to put on and get the whole exhaust re-done. i'm planning on doing complete exhaust and porting the throttle body. i'm mainly looking for better fuel mileage and more bottom end and part throttle power. sometimes going 65/70 on the highway it wont hold overdrive on hills with my 305/70's. i'm just curious as to how much bottom end power i'll actually see from the headers before i drop the money. i know they'll increase high rpm power, but i'm just looking for bottom end. and if midlengths will give me just as much bottom end or more than the long tubes.

**1988 GMC 355** · 04-09-2012, 10:03 AM

WIth the right setup after the LT's you will have awesome low end power, you need an H pipe before the mufflers to help with scavenging and exhaust velocity. The midlength will work too, but if you are doing it all new then go LT's.

**treefiddy** · 04-09-2012, 10:54 AM

you think 2 1/4'' pipe would be best? i already have the mufflers and they're 3'' but i'm just going to reduce them down. so i'd be running long tubes, to an H-pipe, then the 2 flowmaster single chambers all with 2 1/4'' pipe. no cats.

**1988 GMC 355** · 04-09-2012, 12:20 PM

SOunds great to me, since you already have the mufflers just make them work

**treefiddy** · 04-09-2012, 12:35 PM

good deal. i think it'll be pretty loud but i've liked these mufflers on a lot of other set-ups i've heard so it should sound alright.

**1988 GMC 355** · 04-09-2012, 01:20 PM

How are you going to have them exit?

**treefiddy** · 04-09-2012, 09:17 PM

i'm debating on either running 45 degree tips out the back or just running the pipe over the axle and then painting the pipe black to hide them. i kind of like the clean look of no tips, but i haven't decided for sure yet.

**ChevyLs1z** · 04-23-2012, 07:39 PM

I don't know about them on a truck...but I have a ls1 camaro with hooker longtubes, true duals and super 10 flowmasters...they sound great

**treefiddy** · 04-25-2012, 01:07 PM

actually the mufflers are from an old true dual set-up i had on my ls1 camaro with long tubes too. they did sound great on that car.

**07tbss** · 05-05-2012, 01:32 PM

Originally Posted by treefiddy

actually the mufflers are from an old true dual set-up i had on my ls1 camaro with long tubes too. they did sound great on that car.

I can tell you one thing for sure...its going to be stupid loud...lol. I have some stainless mid lengths off ebay, 2.5 true duals to 2.5" single chambers dumped out toward the pass side rear wheel. I didnt really think at the time to put in an H pipe. I does sound a little raspy at WOT but still good. I have a crappy cell phone video of it running on the last page of my build thread. Its the 1990 build thread in my sig.