340/mag360 exhaust manifolds

mopar56 said
yeah, that's it!, now how much difference in performance do you think that would make over the 318 one I have?, what I would have to do is use the 1980 318 truck one I have on the p/s to match diameter of exhaust, could this one be machined bigger? and how much do you want for it if it would work?, this must be a 69 340 d/s one that you have I presume?,thanks again for your help.

The truck manifold you have doesn't have a lot of material like the 360/Dakota manifolds but it probably could be taken out another 1/16" or maybe 1/8". It's hard for me to tell without looking at it personally. If it's like the one (truck 318) I have then I could check. Actually these 340 manifolds (small ones) were used in the 70s (1 7/8"). I could machine it but it doesn't have as much material as the 360/Dakota manifold so the biggest I would try and make it is 1 15/16" or 1/16 short of 2". I believe it is a driver's side but probably 70s. The 340 (like this one) is a hair over 1 7/8" which is 1/4 larger than a stock 318, so that's probably around 10-15 percent more flow. At 1 5/16" it would be more of course. You have to remember, these were used on the factory 340 engines and those engines were fairly powerful!! I would sell this one the way it is for $100 PLUS SHIPPING and "machined" for $140 PLUS SHIPPING. It's already been sand blasted, painted with high heat paint and "heat" cured.

Treblig