dual 3" into single 3.5"
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From: morrow, ga
Car: 82 S10, 83 280ZX, 84 Z28
Engine: 355 smallblocks..na, 2.8 turbo
Transmission: 85:th350, 84:700R4
Axle/Gears: 85:ford9 4.85, 84:stock 3.24
dual 3" into single 3.5"
this is an update to my earlier thread to give some of you guys some ideas on an exhaust system. i decided to go dual 3" into a single 3.5". this system stops at the rear axle for now. i used all "off the shelf parts". the parts used are hedman 1 5/8" long tubes pn 68460, hedman header extensions qty(4) pn 18701, flowmaster y pn y300350, and qty(2) 3"x3" id connectors from autozone. you'll need hangers, and clamps if you're not welding it. i will try to upload some pics of the system on the car soon. thanks for looking guys...
Last edited by skirkland1980; Feb 20, 2010 at 02:03 AM.
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From: Cypress, California
Car: 1989 GTA
Engine: 369 TPI
Transmission: 4L60E
Axle/Gears: 3.70 Nine Bolt
Re: dual 3" into single 3.5"
That is what I'm currently running only with 3" catalytic converters thrown in the mix. Routing all on the passenger side.
Thread Starter
Supreme Member
iTrader: (2)
Joined: Jul 2009
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From: morrow, ga
Car: 82 S10, 83 280ZX, 84 Z28
Engine: 355 smallblocks..na, 2.8 turbo
Transmission: 85:th350, 84:700R4
Axle/Gears: 85:ford9 4.85, 84:stock 3.24
Re: dual 3" into single 3.5"
are you running long tube headers? do you have pics?
Thread Starter
Supreme Member
iTrader: (2)
Joined: Jul 2009
Posts: 1,354
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From: morrow, ga
Car: 82 S10, 83 280ZX, 84 Z28
Engine: 355 smallblocks..na, 2.8 turbo
Transmission: 85:th350, 84:700R4
Axle/Gears: 85:ford9 4.85, 84:stock 3.24
Re: dual 3" into single 3.5"
thats cool. i got really screwed when i took my other camaro to a muffler shop when they built my exhaust system. when they made the y pipe they just burned a small half dollar size hole where they t'd in the right side pipe.(caused a lot of restriction) well, it did ok until i built a new, more powerful engine. i went from running 9.3 1/8 mile to 10.5 1/8 mile. when i removed to system completely it ran a 8.17.
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iTrader: (3)
Joined: Sep 2003
Posts: 6,859
Likes: 14
From: Cypress, California
Car: 1989 GTA
Engine: 369 TPI
Transmission: 4L60E
Axle/Gears: 3.70 Nine Bolt
Re: dual 3" into single 3.5"
"they just burned a small half dollar size hole"
That will cost a lot of horsepower. A good wye is worth some ponies.
That will cost a lot of horsepower. A good wye is worth some ponies.
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Joined: May 2005
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From: Winnipeg, Manitoba. Canada
Car: 1989 T-Top GTA
Engine: 5.7L TPI> 6.2L
Transmission: 700R-4
Axle/Gears: 3.27
Re: dual 3" into single 3.5"
I'm planning kinda the same thing, but I'm gonna go 3" homemade Y-pipe into a 3" Single Flowmaster Cat-back system I'm already running. The crush bend system that the exhaust shop built sucks a**........... (search for yourself)
I've bought a tranny cross member that I'll clearance somewhat for the y-pipe to run underneath....
Please post pics as you go I'm very interested!!!!
I've bought a tranny cross member that I'll clearance somewhat for the y-pipe to run underneath....
Please post pics as you go I'm very interested!!!!
Last edited by GTA Sammy; Feb 22, 2010 at 11:43 PM.
Thread Starter
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From: morrow, ga
Car: 82 S10, 83 280ZX, 84 Z28
Engine: 355 smallblocks..na, 2.8 turbo
Transmission: 85:th350, 84:700R4
Axle/Gears: 85:ford9 4.85, 84:stock 3.24
Re: dual 3" into single 3.5"
i just installed the moroso spiral muffler pn 94052 ($52) and i thought i would voice my opinion about it. i absolutely love it! it is very compact, and sounds amazing. its fairly quiet which makes it great for a daily driver and because my system stops at the rear axle. it also gave me just enough back pressure (compared to open pipes) to help my torque. it feels stronger from a stop.
Thread Starter
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iTrader: (2)
Joined: Jul 2009
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From: morrow, ga
Car: 82 S10, 83 280ZX, 84 Z28
Engine: 355 smallblocks..na, 2.8 turbo
Transmission: 85:th350, 84:700R4
Axle/Gears: 85:ford9 4.85, 84:stock 3.24
Re: dual 3" into single 3.5"
cool. all those pipes and y are available in smaller sizes also. and any short small diameter muffler will work, like the flowmaster outlaw or a glasspack.
Thread Starter
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iTrader: (2)
Joined: Jul 2009
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From: morrow, ga
Car: 82 S10, 83 280ZX, 84 Z28
Engine: 355 smallblocks..na, 2.8 turbo
Transmission: 85:th350, 84:700R4
Axle/Gears: 85:ford9 4.85, 84:stock 3.24
Re: dual 3" into single 3.5"
i finally posted a video clip for how the car sounds. let me know what you think. http://www.youtube.com/watch?v=wZNeOkRqse0
Thread Starter
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iTrader: (2)
Joined: Jul 2009
Posts: 1,354
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From: morrow, ga
Car: 82 S10, 83 280ZX, 84 Z28
Engine: 355 smallblocks..na, 2.8 turbo
Transmission: 85:th350, 84:700R4
Axle/Gears: 85:ford9 4.85, 84:stock 3.24
Re: dual 3" into single 3.5"
the only clearance problem i had was around the torque arm, so i just dented the pipe a little. but now i made my own torque arm and have about 3" of clearance there. if you use 2" or 2.5" pipe there may not be a clearance issue.
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Joined: Aug 2007
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From: Leicester,Ma.
Car: 1988 TA
Engine: TPI 350
Transmission: auto
Axle/Gears: 3.27's
Re: dual 3" into single 3.5"
If you get a chance take a picture please with it on the car im very interested in doing this for mine it looks great
Thread Starter
Supreme Member
iTrader: (2)
Joined: Jul 2009
Posts: 1,354
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From: morrow, ga
Car: 82 S10, 83 280ZX, 84 Z28
Engine: 355 smallblocks..na, 2.8 turbo
Transmission: 85:th350, 84:700R4
Axle/Gears: 85:ford9 4.85, 84:stock 3.24
Re: dual 3" into single 3.5"
thanks. sorry its taking so long between posts, I'm starting a new job and been busy.
Thread Starter
Supreme Member
iTrader: (2)
Joined: Jul 2009
Posts: 1,354
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From: morrow, ga
Car: 82 S10, 83 280ZX, 84 Z28
Engine: 355 smallblocks..na, 2.8 turbo
Transmission: 85:th350, 84:700R4
Axle/Gears: 85:ford9 4.85, 84:stock 3.24
Re: dual 3" into single 3.5"
i sold the system to another member. here are some pics of it on his car.
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From: Florissant, (STL) MO
Car: 1985 Camaro Z28
Engine: LT1
Transmission: 4L60e/SS3600
Axle/Gears: S60/4.30/Spool
Re: dual 3" into single 3.5"
Looks good. I will be building something like this soon. My plan involves relocating the "frame rails" and rebuilding the trans crossmember so I can run 3" next to the trans and over the crossmember. Should free up some ground clearance I am loosing to my 2.5" x-pipe set up.
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From: Leicester,Ma.
Car: 1988 TA
Engine: TPI 350
Transmission: auto
Axle/Gears: 3.27's
Re: dual 3" into single 3.5"
hmm it looks good..only problem im thinking im gonna have is it scraping because my car is lowered about 2 inches im assuming you had the car at stock ride height?
Thread Starter
Supreme Member
iTrader: (2)
Joined: Jul 2009
Posts: 1,354
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From: morrow, ga
Car: 82 S10, 83 280ZX, 84 Z28
Engine: 355 smallblocks..na, 2.8 turbo
Transmission: 85:th350, 84:700R4
Axle/Gears: 85:ford9 4.85, 84:stock 3.24
Re: dual 3" into single 3.5"
yes, using longtubes are a problem on lowered cars unless you want to seriously mod the underside of the car. since the pipe is 3" i lost 3" of ground clearance.
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Joined: Aug 2007
Posts: 483
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From: Leicester,Ma.
Car: 1988 TA
Engine: TPI 350
Transmission: auto
Axle/Gears: 3.27's
Re: dual 3" into single 3.5"
this could be interesting..i suppose i could always raise the car back up if i need to i ordered the stuff from jegs today to make a 2.5 version of your y pipe hopefully the half inch will help my clearance a little.
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Joined: Mar 2010
Posts: 69
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From: NORFOLK VA
Car: 84 Z28 / 99 S-10 ZR2 4X4
Engine: STOCK CARB'D 305 WITH 350 HEADS
Transmission: 700R4
Axle/Gears: STOCK
Re: dual 3" into single 3.5"
Hey guys!!! I'm the one Shane sold those 3in pipes to and I haven't had a problem so far. Clearance has been fine, but I am running larger tires so that could make a difference. I would like to know if using thermal wraps on the headers would make a difference in temp under the hood though.
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