I was planning on putting true dual exaust on my 1988 firebird 305 TBI but im trying to find the best way to do this. Any help on the subject and or pictures would be helpful.
Thanks in advance Chris

 

There are several other threads in this forum about this topic. Please read them.

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1991 Camaro Z28
5.7L 5-Speed (originally 305)
13.25 @ 107.18 MPH
Southern California
Member: SoCal 3rd Gen F-Bodies
Webmaster: SoCal F-Bodies
-=ICON Motorsports=-

 

dude it would be the worst thing u could ever do as a first mod. U loose all ur low end torque, its expensive and it would never work right. My father tried this on his 82 trans am. He spent alot (and i mean alot) of money going from shop to shop having pipe best just to get it to work. It never did. i mean it was in here but it was just so rigged up looking. If u really want an exahaust go with a high flow cat back. But to be competly honest i would go with gears as ur first mod. For about the same price as the true dual set up would end up costing , u could have had a nice set of 3.73 gears and a mild shift kit installed. This increase is way more noticeable.

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1989 pontiac firebird
bright red exterior(just repainted)
grey interior
5 spd
305 TBI (stock)
WS.6 formula wheels
3.73 posi rear end
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system: 2 10" MTX thunder 2000 in a Professionally done custom bandpass box.
Blaupunkt CD player
Blaupunkt 4x6 and 6x9
600 watt rockford fosgate 4.6 amp

thinking about a flowmaster

 

I just had dual exhaust put on my car and it works perfectly...

No scraping...or anything. I didn't notice any loss in power either. I'm not sure what the other guy is talking about.

My setup is the stock exhaust manifolds, then two 2.5" pipes going into two 2-chamber flowmasters where the cat used to be. and then running side by side...going over the axle and exiting at the stock locations...

It did cost a lot though...total cost after everything was around 550...but the mufflers were 100 bucks each...so if you get cheaper mufflers, it'll save money..

 

gsmann,

Being from Cali, how do you pass emissions checks (visual) with duals and no cats? I'm surprised the muffler shop even did that kind of work...most muffler shops won't even do that for fear of getting fined for tampering with the cats.

Not a flame, just curious...

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1989 IROC-Z, ZZ3 shortblock with some bolt-ons.
13.20 @ 108.69, 2.2 60'

 

ummmm ok y would u pay that kind of money for a rigged up exhaust when u could either get a performance oem replacement for alot less (probably good for more power than the dual set up) or jst put ur money into a worth while mod. A high flo exahaust isnt gonna do that much on a stock 305.

 

Well actually..after putting in a new 350 with 110 ls cam, new injectors, adj fuel regulator, accel super coil, tricked tranny, intake, and level IV custom prom....i felt dual exhaust did its job...it a lot faster than with my 80 series flowmaster...

well worth the money...

 

gs man - What kind of et drop did you see?

 

hey, gs mann. how do you pass smog here in San Jose,CA without cats.

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RED82TA5.7L

1982 Pontiac Trans Am
Cross-Fire Injected 5.7l V8
Eldebrock Headers, 3" Hooker Cat-Back, 2 nice tips with duel outlet on each side.
Mods: 1.6 Proform Roller Rockers, electric fan.

Future mods: X-Ram( Aftermarket Cross-Fire Injection Manifold that proves to have as much power as TPI www.x-ram.com )
Cross-Fire Injection after market chip that says that it will proform like 90's injections.. http://www.turbocity.com/CorvetteCro...ECMUpgrade.htm

 

Im sure hes not worried about smog stuff if he got it done. If he is he proably knows a buddy that works at a shop or will bolt on his stock exhaust (if possible)

Im sure dual exhaust will help out. Its not like hes going to dual 3" exhaust or anything like that, its only 2.5". Mustang with a little 302 come with that so whats the big deal?

 

I haven't ran an ET yet...but it definitely kicks on the freeway and thar feels a lot quicker off the line....

it's not like i lost any backpressure...it's only 2.5" and it goes all the way back....i just don't have turn downs after the muffler or anything...

I don't worry about smog here in san jose....i have a guy that'll pass me for 50 bucks..

 

LUCKY GUY. i hate smog

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RED82TA5.7L

1982 Pontiac Trans Am
Cross-Fire Injected 5.7l V8
Eldebrock Headers, 3" Hooker Cat-Back, duel outlet with quad tips.
Mods: 1.6 Proform Roller Rockers, electric fan.

Future mods: X-Ram( Aftermarket Cross-Fire Injection Manifold that proves to have as much power as TPI www.x-ram.com )
Cross-Fire Injection after market chip that says that it will proform like 90's injections.. http://www.turbocity.com/CorvetteCro...ECMUpgrade.htm