340 cam, converter

Car is pretty much a Frankenstein. Originally 71 318 duster. Was my brother’s since late 70’s and swapped in a 340 from a 68 barracuda. Rear from a 73, A body(3:55 posi). I believe it has a 904 3spd transmission. A friend of his back in the day out a high lift cam 850 carb which made no sense. As I grew up learning about cars in general I’ve done some work to it in time. As he’s getting older, I want to build a solid street able motor. The 68 340 ran just fine before engine was removed. Plan on taking heads(x heads) and inspecting. It does not have the hardened seats and have read that people still run unleaded gas and not worry. Then again if I’m going to replace seats with hardened and springs/retainers and possible guides if needed might as well just get an aftermarket? Any recommendations on brands? If able to stay with stock seats, obviously I’d change springs and check guides. Can anyone recommend a cam with either stock X head or cam/head combo. Has an edelbrock rpm intake manifold and I believe last 650 Holley carb which replaced the 850 which it used to have. Is there a cheap alternative to the 904 that would fit stock location and transfer of parts or just build the 904? Any recommendation for converter? I know 727 are hard to come by. Would a 46re from a 2wd ram fit in stock location of 71 duster? Any help on recommendation for replacement parts such as head gaskets, head bolts. Cam springs. As for lifters are hydraulic flat tappets better than solid lifters? I’ve been reading lately as of brand new cam/ lifter failures from cheap material regardless where it’s bought.


First, welcome to FABO... wave.gif Welcome to FABO.gif

for cam, you need to decide on what you are going to do with the car and then that will determine what size cam to choose... The cam will determine what size/rate springs will be needed...

Solid lifters will have to be adjusted periodically, hydraulics don't...

We worked with Oregon cams to make a reproduction 68 340 4 speed cam which is one step above the stock 340 automatic cam which would be a good choice for a street/strip engine:

Reproduction 340-4 Speed Cam


I ran an engine without hardened exhaust seats and the valves beat the **** out of seats and sunk the valves within 10,000 miles without lead or lead substitute in the gas... --->>> I recommend having hardened seats installed on the exhaust valves.... Replace the guides if they are worn...

Small block 727's aren't hard to come by, keep an eye out for one or place a wanted ad on here and wait for replies.... 360's have a different balance than the 318/340 make sure to get the proper balanced torque converter for your application...