1973; 318 vs 340 manifolds

[swing69]

I'm putting in a 340 into a 73 Dart. Originally, it had a 318 with stock manifolds.

How different are the 340 vs 318 manifolds?

Are the 340 ones worth getting? expensive?

I don't really want to go with headers because of leaking issues...but if I did, what is the best fitting?

 

[wish4hemi]

It depends on what kind of power you want to make. On a stock 340, I would say the 318 manifolds will not hurt horsepower that much. And yes, factory 340 manifolds are very expensive. $400-$700 range. Can't beat the performance of headers, especially if you have done any kind of performance work on the 340. tti's are probably the best and very pricey. Lots of different header manufacturers though. There are a few threads around here on what headers fit best and why.

 

[beepahh]

are you gasket matching the maniflolds and heads? HP 340 manifolds outflow the 318's by about 30% had them cheched on my build recently......not many headers outflow the 340's due to their unique design....think about it.......and what you want out of the motor

 

[wish4hemi]

Here's a good exhaust manifold comparison Mopar Muscle did a while back. They tested everything from 318 manifolds to tti's. http://www.moparmusclemagazine.com/...0307_mopar_crate_engine_exhaust/photo_17.html

 

[GupsTateS]

Makes me slightly reconsider taking my headers off for the 340 manifolds. Thanks for the article. I didn't realize I would be giving up so much.

 

[Babyblue66]

Thats a pretty mild engine though. I think results might be different if it had more cam.