89 N10 swap into and 86 Trans Am
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89 N10 swap into and 86 Trans Am
I did try searching but probably asked the wrong question. Has anyone swapped an N10 exhaust into a car that didn't have it originally. I have an 89 parts car with the N10 dual cat and want to put it in my restorabe 86. What problems if any? how tricky if it was? I have owned a 70 GTO and, 77 Formula and an 81 Trans Am so I'm new to the 3rd Gen world. Any help is appreciated.
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From: NYC
Car: 1982 Recaro TA, 1989 TTA#948
Re: 89 N10 swap into and 86 Trans Am
I would say the biggest problem is the condition of those old cats. If you are really hell bent on swapping in the dual cats, you can get a replacement from Rock Auto. Those used cats are probably well below peak efficiency turning into a tremendous amount of added back pressure. If you are in an area that does not test for emissions, a good set of headers and matching crossover pipe will get you the free flowing exhaust you are looking for.
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Re: 89 N10 swap into and 86 Trans Am
I'm in Michigan but they don't check emissions yet. Headers are in the future with the emission tubes. I'm thinking the N10 just because I have it available. The 350 from the 89 will makes its way into the 86 after a rebuild. I want to stay emissions legal just in case. thanks for the help
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From: Des Moines, Iowa
Car: 89 Formula
Engine: Nada - v4.0
Transmission: Nada - v3.0
Axle/Gears: Nada - v3.0
Re: 89 N10 swap into and 86 Trans Am
Take the N10 y-pipe to an exhaust shop and have then cut out the cats and replace them with straight pipe. If I remember correctly, you may have to deal with one hanger but the other stuff should not be a problem.
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From: Orange, CA
Car: '90 Trans Am-12.45@110.71
Engine: 355 w/AFR 195's Elem. 400/430 HP/TQ
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Re: 89 N10 swap into and 86 Trans Am
The exhaust manifolds are different too between '86 '89
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From: Des Moines, Iowa
Car: 89 Formula
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Transmission: Nada - v3.0
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Re: 89 N10 swap into and 86 Trans Am
If you have both,just use the 89 manifolds so their are no potential issues.
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From: Chicagoland
Car: 1989 IROC-Z. Original owner
Engine: LB9. Dual Cats. Big Cam
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From: Chicagoland
Car: 1989 IROC-Z. Original owner
Engine: LB9. Dual Cats. Big Cam
Transmission: World Class T-5
Axle/Gears: BW 3.45
Re: 89 N10 swap into and 86 Trans Am
The definitive post on 3rd gen exhaust...
There were only 2 different manifolds for the V8's throughout the years, but they were different depending on what motor and gearing package they came on. Here is the breakdown.
2" outlet manifolds with single 2 1/4" y-pipe
82-87 305 LG4 (VIN H)
88-92 305 L03 (VIN E)
82-83 305 Crossfire
90-92 305 LB9 w/o G92 axle (VIN F)
2 1/4" outlet manifolds with single 3" y-pipe
83-86 305 L69 (VIN G)
85-89 305 LB9 (VIN F)
88 350 L98 (VIN 8)
89 350 L98 w/o G92 axle (VIN 8)
2 1/4" outlet manifolds with dual 2 1/4" cats
89 350 L98 w/G92 axle (VIN 8)
90-92 350 L98 (VIN 8)
89 305 LB9 w/G92 Axle (VIN F)
90-92 305 LB9 w/G92 (Vin F)
The manifolds from the single 3" cat and the dual 2.25" cats are interchangeable. On the passenger side manifold, some will have the heat riser butterfly valve, some will have a spacer, and some will just have a donut gasket. You most likely have the wrong manifold for your application. If you have the larger manifolds, then it may be worth it to get the larger y-pipe for some more performance.
2" outlet manifolds with single 2 1/4" y-pipe
82-87 305 LG4 (VIN H)
88-92 305 L03 (VIN E)
82-83 305 Crossfire
90-92 305 LB9 w/o G92 axle (VIN F)
2 1/4" outlet manifolds with single 3" y-pipe
83-86 305 L69 (VIN G)
85-89 305 LB9 (VIN F)
88 350 L98 (VIN 8)
89 350 L98 w/o G92 axle (VIN 8)
2 1/4" outlet manifolds with dual 2 1/4" cats
89 350 L98 w/G92 axle (VIN 8)
90-92 350 L98 (VIN 8)
89 305 LB9 w/G92 Axle (VIN F)
90-92 305 LB9 w/G92 (Vin F)
The manifolds from the single 3" cat and the dual 2.25" cats are interchangeable. On the passenger side manifold, some will have the heat riser butterfly valve, some will have a spacer, and some will just have a donut gasket. You most likely have the wrong manifold for your application. If you have the larger manifolds, then it may be worth it to get the larger y-pipe for some more performance.
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Re: 89 N10 swap into and 86 Trans Am
Thank you all for the help and advice. Headers will eventually be on the car but that is a distant project. I was looking to up performance with what I have available right now. The 86 has the TPI 305 as of now. Eventually the L98 will be replacing that. when I do a rebuild I'll be looking to make 350hp.