Exhaust manifolds 110hp vs 140 hp

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Location: porter texas

Exhaust manifolds 110hp vs 140 hp

Unread post by my65 » Wed Sep 06, 2017 2:55 pm

The PO of my 63 coupe has had it's engine changed out to a 1965 110 hp. After some time he had a valve sucked in and replaced the heads with 140 hp ones. ( now have 4 carbs) I removed the mufflers and was putting a Clark's
( c1046r) u pipe on to hot adjust the lifters when I found the exhaust manifold flange gasket on the mufflers where smaller than the ID of the
u pipe?! Can 110 hp manifolds properly be installed on 140 hp heads???? And if so, do you lose power with the smaller exhaust muffler and pipes??
Ed ( my65 )
65 Monza Convertible
110 HP 4 Speed
63 Monza Coupe
140 HP 4 Speed
Porter, Texas

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Re: Exhaust manifolds 110hp vs 140 hp

Unread post by bbodie52 » Wed Sep 06, 2017 3:20 pm

The 140 hp engine was the only Corvair engine with larger exhaust manifold packings at the heads and the crossover/muffler attachment. See the dimensions listed at the center of the page below...

:link: http://www.corvair.com/user-cgi/catalog ... AIN&page=7

The 140 hp heads were designed with larger valves for greater airflow capacity to take advantage of the 4x1 carburetors. The large capacity dual exhaust and exhaust manifolds completed the design.
Brad Bodie
Lake Chatuge, North Carolina
Image 1966 Corvair Corsa Convertible

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