Exaust manifold: 2" or 2 1/2"
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From: Wyandotte MI
Exaust manifold: 2" or 2 1/2"
My 69 has a 65 327 in it. How do I tell if its the 2" or 2 1/2" manifold? What do I measure--the pipes bolted to it or part of the manifold itself? And what should the #'s be? Just want to make sure if I measure the pipes that it is an accurate way. Thanx :D
Melting Slicks
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From: OKC Oklahoma
Re: Exaust manifold: 2" or 2 1/2" (Sixty9)
Measure the inside diameter. According to my interchange manual, if your car originally came with a 350(that's the only small block they list) the driver's side part number is: 3846559
this part number was used on 1967-1968 Corvette 327 with AIR,1969-1971 Corvette 350 except LT-1, and some trucks
The passenger side part number is: 3893604 however the casting number is different:3932465
this part number was used on 1968-1971 Corvette 350, 1968 Corvette 327 and some Impalas
this part number was used on 1967-1968 Corvette 327 with AIR,1969-1971 Corvette 350 except LT-1, and some trucks
The passenger side part number is: 3893604 however the casting number is different:3932465
this part number was used on 1968-1971 Corvette 350, 1968 Corvette 327 and some Impalas
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From: Wyandotte MI
Re: Exaust manifold: 2" or 2 1/2" (79VetteMike)
Thanx for the part #'s Mike! :thumbs: I'll check those tommorrow. I figured I could measure the inside diameter, but I don't want to take it apart(probably wouldn't come apart anyways)was hoping for an easier method measuring from the outside on either the manifold or the exhaust pipe. I want to find out(for side pipes) whether I need 2" or 2 1/2" small block.
Melting Slicks
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From: OKC Oklahoma
Re: Exaust manifold: 2" or 2 1/2" (Sixty9)
It's my pleasure to help. I'm just glad to see this book going to good use, because my car is far from stock, but I like it that way. The interchange manual doesn't tell which ones are 2" and which are 2 1/2".
Safety Car
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From: Fountain Hills AZ
Re: Exaust manifold: 2" or 2 1/2" (Sixty9)
If your they used the `65 manifolds when they swapped engines they might be 2.5's. `65 was the last year for 2.5's (250 hp and 300 hp autos had 2"). `66 on were all 2". Part numbers for non-FI 2.5's are 3846563 left, 3797902 right (3797942 w/AC). FI manifolds are 3797942 left, 3797902 right. All other manifolds were 2".
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From: Wyandotte MI
Re: Exaust manifold: 2" or 2 1/2" (Vetterodder)
Thanx Vetterodder, I went out to the garage to get some #'s---drivers side looks like 3872765 and pass. side 3832465 which is close to what Mike posted. I may have read it wrong. Thanx for the help(IM) again Mike :D
Race Director
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From: San Jose CA
Re: Exaust manifold: 2" or 2 1/2" (Sixty9)
Just measure the circumference of the exhaust pipe directly below the exhaust manifold outlet, divide by 3.14159 and badabing badaboom. If you have a caliper, you need only measure the diameter there.
-Steve
*edit* I should say, there's no way to get a 2" pipe in a 2.5" manifold, or vice versa. The former would have a huge leak, the opposite would not fit.
[Modified by Pacin'California, 8:32 PM 9/2/2003]
-Steve
*edit* I should say, there's no way to get a 2" pipe in a 2.5" manifold, or vice versa. The former would have a huge leak, the opposite would not fit.
[Modified by Pacin'California, 8:32 PM 9/2/2003]
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From: Vancouver BC
Re: Exaust manifold: 2" or 2 1/2" (Pacin'California)
*edit* I should say, there's no way to get a 2" pipe in a 2.5" manifold, or vice versa. The former would have a huge leak, the opposite would not fit.
Safety Car
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From: The reason time exists is so everything doesn't happen at once
Re: Exaust manifold: 2" or 2 1/2" (VetticusSupersonicus)
1965 as the last year for the 2 1/2" exhaust manifold on a small block. After that they were all 2". On cars with 2 1/2" exhausts (LT-1's for example) the exhaust pipe was necked down just before it entered the manifold.
