Dual Exhaust

Scott03 · Post by **Scott03** » Mon Dec 08, 2003 11:30 am

Well, a bargain came my way over the weekend. A guy I work with offered to sell me his tonneau cover that he had on his Zr5 (he bought a topper) for 100$. Its pretty nice and lockable. Any way after I have that installed I will put that spare tire mount in the bed.

Now that I have all that room underneath I wanted to put dual exhaust on the truck. I know some of you have duals already, just need some info on them.

What type of set up do you have, how much did it cost (supply cost - my bro is a gm tech, and we have access to the equipment).

Just any info would be great.

Thanks

Jim · Post by **Jim** » Mon Dec 08, 2003 2:06 pm

Scott03 wrote:Well, a bargain came my way over the weekend. A guy I work with offered to sell me his tonneau cover that he had on his Zr5 (he bought a topper) for 100$. Its pretty nice and lockable. Any way after I have that installed I will put that spare tire mount in the bed.

Now that I have all that room underneath I wanted to put dual exhaust on the truck. I know some of you have duals already, just need some info on them.

What type of set up do you have, how much did it cost (supply cost - my bro is a gm tech, and we have access to the equipment).

Just any info would be great.

Thanks

I don't want to burst your bubble but.
After all the research I have done duals with exits on both sides of the rear axel are near impossible to do neatly. We have a gas tank in the way & not enough room over the axel. The only clean way I can see doing duals would be if they both exit where the stock one does as older full sized trucks did.

AZS10Crew · Post by **AZS10Crew** » Mon Dec 08, 2003 2:15 pm

Whcih spare tire mount are you getting? Hopefully the flat one.

Don't know if any custom fabrication would be a possibility for you, but I've always thought using an F-body single in/dual out exhaust might work with the spare removed. You could use the stock pipe placement (replacing the stock muffler with a straight pipe)through just after the axle, turn it towards the driver side, into the new F-body style muffler, then out each side of the muffler then turn them to exit the rear. Kind of like this...

_|___[

where the dash in the upper right is the inlet, and the dashes in the lower left and right are the outlets that would be turned toward the back.

Just a thought...

Scott03 · Post by **Scott03** » Mon Dec 08, 2003 3:45 pm

Hopefully the flat one.

, ya the flat one

Thanks for the info, I guess anything could be done, its just a matter to money and fabrication.

Since I don't have a lot of either, I think I may have to rethink the dual idea. Maybe just do single exit, basically replacing the stock with flowmaster and new piping and nice tip (maybe twin tip)....hmmmm

AZS10Crew · Post by **AZS10Crew** » Mon Dec 08, 2003 4:18 pm

Or just do a straight pipe and a turn-down so you don't have departure angle issues with nice shiny chrome tips...and no muffler is cheaper too.

Justin · Post by **Justin** » Mon Dec 08, 2003 4:30 pm

if you plan on keeping the truck a while, have a professional do it with stainless steel pipes. There is plenty of room if you remove the spare tire and run the pipes over the axle. Opt for 2.5" or bigger to get a meatier tone and you can do it without a muffler. If you care less about it rotting away after a couple of years, any muffler shop could rig soemthing up in an hour or two for about $300. I got a quote for stainless steel in which it will take the guy 2 days!

3.5" piping from where the two manifolds come down, a high flow catalytic converter, 3.5" - (2) 3" Y pipe, then 3" piping all the way to the back with some big 4" tips

= $750

NTXCrew · Post by **NTXCrew** » Tue Dec 09, 2003 9:14 am

Just a thought, but I think that 3.5 in is going to be way to big. Big enough to hurt performance. Coming out of the manifolds is only like 2.25 inches. I've read that if you enlarge the diameter of the piping too soon, it allows for the gases to simply expand into the larger volume of piping instead of encouraging them to scavenge, or flow out the exhaust tips. SLP makes a performance y-pipe and it is 2.25 in. It simply has a much "smoother" design. The key to remember is that we don't a big V-8 engine (at least not yet!

).

Dragonmaster · Post by **Dragonmaster** » Tue Dec 09, 2003 10:54 am

Justin wrote:if you plan on keeping the truck a while, have a professional do it with stainless steel pipes. There is plenty of room if you remove the spare tire and run the pipes over the axle. Opt for 2.5" or bigger to get a meatier tone and you can do it without a muffler. If you care less about it rotting away after a couple of years, any muffler shop could rig soemthing up in an hour or two for about $300. I got a quote for stainless steel in which it will take the guy 2 days!

3.5" piping from where the two manifolds come down, a high flow catalytic converter, 3.5" - (2) 3" Y pipe, then 3" piping all the way to the back with some big 4" tips

= $750

Whoa, that may work on a duramax, but our engines simply do not have the displacement to scavenge in a volum that large, a 2.25" or 2.5" y pipe should be sufficient with a 3" pipe after tha cat.

Justin · Post by **Justin** » Tue Dec 09, 2003 2:46 pm

I've heard of some 2wd 4.3L with dual 2.5" setup. The guy who does the exhaust work does custom car and truck exhausts and he prefers to work with 2.5" or bigger. He also said that its best if there are minimal bends in the pipe. If i keep the truck, im going to have it done because I do not like the setup i have now. I think it is robbing hp than gaining

Jay-Bird · Post by **Jay-Bird** » Tue Dec 09, 2003 4:53 pm

Theres some one in West Monroe, Louisiana that has dual exhaust on a ZR5 and they look good, if i can catch the person this weekend I am going to ask them where they got it done at.. and give them this website...

adrenalnjunky · Post by **adrenalnjunky** » Wed Dec 10, 2003 8:25 am

I've seen that guy around town. I've been kicking around duals (with quiet mufflers) and a throttlebody spacer to try and get my MPG up a little -- anyone think that should work?

Dragonmaster · Post by **Dragonmaster** » Wed Dec 10, 2003 8:35 am

adrenalnjunky wrote:I've seen that guy around town. I've been kicking around duals (with quiet mufflers) and a throttlebody spacer to try and get my MPG up a little -- anyone think that should work?

I've got a throttle body spacer on my 4.3 and I haven't seen an increase yet, but that may be because I haven't reset the computer yet?

AZS10Crew · Post by **AZS10Crew** » Wed Dec 10, 2003 1:39 pm

Dragonmaster wrote:
adrenalnjunky wrote:I've seen that guy around town. I've been kicking around duals (with quiet mufflers) and a throttlebody spacer to try and get my MPG up a little -- anyone think that should work?
I've got a throttle body spacer on my 4.3 and I haven't seen an increase yet, but that may be because I haven't reset the computer yet?

The computer resets itself after about 50 miles or so.

AZS10Crew · Post by **AZS10Crew** » Wed Dec 10, 2003 1:40 pm

Dragonmaster wrote:
adrenalnjunky wrote:I've seen that guy around town. I've been kicking around duals (with quiet mufflers) and a throttlebody spacer to try and get my MPG up a little -- anyone think that should work?
I've got a throttle body spacer on my 4.3 and I haven't seen an increase yet, but that may be because I haven't reset the computer yet?

The computer will adjust itself after about 50 miles or so.

TruStinger · Post by **TruStinger** » Fri Dec 12, 2003 12:07 am

3.5 exhaust?? are you on crack? anything bigger than 2.5 on an s10 is murder for performance unless you have some major performance mods. the most i could reccomend would be 2.25 in/dual 2 out or 2.5 in/single 2.25 out with daul tip. the only time you woudl need anything bigger would be a supercharger, a turbo or if you drop a v8 in it. unless you have a turbo v8 you should never need 3.5inch exhaust

Dragonmaster · Post by **Dragonmaster** » Fri Dec 12, 2003 8:07 am

TruStinger wrote:3.5 exhaust?? are you on crack? anything bigger than 2.5 on an s10 is murder for performance unless you have some major performance mods. the most i could reccomend would be 2.25 in/dual 2 out or 2.5 in/single 2.25 out with daul tip. the only time you woudl need anything bigger would be a supercharger, a turbo or if you drop a v8 in it. unless you have a turbo v8 you should never need 3.5inch exhaust

I didn't want to be the first one to say it, but TruS

tinger is right

Post by **HenryJ** » Fri Dec 12, 2003 8:11 am

TruStinger wrote:...anything bigger than 2.5 on an s10 is murder for performance unless you have some major performance mods....

I wouldn't call any of my mods "major", that implies internal engine changes.

IMO, 3" catback IS the "sweet spot" for these 4.3L's.

I made the change to 3" before doing many mods , and gained that little bit of tire spin that was lost with the increase in tire size.

I have a buddy that did a similar system on his Highrider and gave it two thumbs up.

NTXCrew · Post by **NTXCrew** » Fri Dec 12, 2003 8:41 am

You're running 3 in SINGLE, though...right?

Post by **HenryJ** » Fri Dec 12, 2003 8:53 am

NTXCrew wrote:You're running 3 in SINGLE, though...right?

Yes, single. Did I misunderstand the statement?

I guess the topic is "dual exhaust"

You're right 2.5" is more than plenty for duals

S-10CREWCAB.NET

Dual Exhaust

Dual Exhaust

Re: Dual Exhaust