mandrel bent 2.5 exh.
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mandrel bent 2.5 exh.
anyone out there make a prebent 2.5 in exhaust for a 69? I mean mandrel bent so theres no kinks all over the place. grrrrrr....also, whats the stock small block exhuast diameter?
[Modified by jonvolk, 5:16 PM 12/22/2001]
[Modified by jonvolk, 5:16 PM 12/22/2001]
Race Director
Joined: Dec 1999
Posts: 19,610
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From: Forked River NJ
Re: mandrel bent 2.5 exh. (jonvolk)
I could not find one so I had one made. The stock exhaust is 2 inch. The LT1 and big blocks used 2 1/2 inch. I did not like the kinks in the stock system and the flow restrictions. I picked up 4 mph in the 1/4 mile by just going to a better exhaust with Flowmaster mufflers.
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Joined: Dec 1999
Posts: 3,602
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From: PA
Re: mandrel bent 2.5 exh.
The stock exhaust diameter for all 1969 Corvettes was 2"... Big block systems started at 2½" and necked down to 2" approximately 4" from the exhaust manifold exit. Small block exhaust was 2" all the way back.
You have several options if you want to switch to a 2½" exhaust system. If you have the stock 2" outlet exhaust manifolds, you can switch to a 1970-72 LT-1 style system. This isn't completely 2½" as it starts at 2" and increases to 2½" about 4" or so from the manifold (exactly opposite a 1969 big block), but it should be readily available and works with the stock 1969 manifolds. A second option is to use the mid year 2½" outlet manifolds and a true 2½" exhaust system. Another option is to switch to headers and go with a somewhat custom 2½" exhaust system. You'll have to decide which direction you want to take.
In any case, what you're asking for isn't all that uncommon. I'd give Mike Allen a call at Allen's Stainless Exhaust at (219) 722-7272; I'd be willing to bet that they've done this before... Good outfit to work with too.
Good luck with your project!
Regards,
You have several options if you want to switch to a 2½" exhaust system. If you have the stock 2" outlet exhaust manifolds, you can switch to a 1970-72 LT-1 style system. This isn't completely 2½" as it starts at 2" and increases to 2½" about 4" or so from the manifold (exactly opposite a 1969 big block), but it should be readily available and works with the stock 1969 manifolds. A second option is to use the mid year 2½" outlet manifolds and a true 2½" exhaust system. Another option is to switch to headers and go with a somewhat custom 2½" exhaust system. You'll have to decide which direction you want to take.
In any case, what you're asking for isn't all that uncommon. I'd give Mike Allen a call at Allen's Stainless Exhaust at (219) 722-7272; I'd be willing to bet that they've done this before... Good outfit to work with too.
Good luck with your project!
Regards,
Team Owner
Joined: Sep 2001
Posts: 30,958
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From: Middletown Connecticut
Cruise-In IV Veteran
Re: mandrel bent 2.5 exh. (jonvolk)
My exhaust ran me 250, and then about 150 to be installed with a mandrel bend for the headers.. it was a header back kit, but my headers are uneven so one side had to be bent up.. not bad over all.. hell jon you heard it.. and if i had known my car would be that good off the line, i woulda ran you from a light
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Joined: Dec 1999
Posts: 4,148
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From: Roxbury NJ
Re: mandrel bent 2.5 exh. (Gordonm)
The standard '68 2.5" exhaust I got from Corvette Central last year does not have any kinks in it at all, mandrel bends, and it was only around $299. (but then I cut it up for straight through Edelbrock stainless mufflers ;))
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Re: mandrel bent 2.5 exh. (Flareside)
hmmm, me being young and broke...anyone here ever just do exhuast dumps out the sides of the car. Im thinkin about using the collector insert discs from cc to quiet it down (ive seen and heard these at the strip before, sound REALLY nice)..and just have a 45* bend and dump out the sides under the rocker panels. :cheers: