340 General Rebuild Info- Cam Recommendations

Mattax said
Here's the catch. Chrysler's published cam specs are unique to Chrysler.
A '71 340 will still have the 340 valves regardles of head casting, and should have the higher compression pistons.
There's engine decoding info in the 'articles' section of the forum.

Unless you have a particular goal and plan, I'd get it running and shake out the issues. Then make whatever mods float your boat.

Depending on what can be done under Calif. smog rules, it will run a little better with a distributor advance curve similar to those that came from Mopar Performance. Basically it allows using a pre-CAP initial timing without jacking up the timing above idle.

Headers will make a noticible difference, but are a royal PIA. Compared to a maverick engine bay, the Demon will seem roomy. However the T-bars make snaking the exhaust relatively challenging. Off the shelf there's really just two choices of manufacture, Dougs or TTI.

I couldn't agree more.

We spend lots of time talking about cams, heads, cabs, etc., and then just throw a distributor into the engine and run it. The distributor advance curve is critical to a good running engine. The exact same engine can run like a pig or a scared ape, depending on carb and distributor tuning.

I totally agree with getting the engine running and then really tune it. Don't just turn a couple idle screws on the carb and be done with it. The 340 is an awesome engine and tuned properly, you may be happy with it as is. From there, you can start to think about cam, head or carb changes. But getting a good baseline first is great place to start.

(By the way, I have 73 Road Runner with a 340 - now a 416 stroker. I've had it for 42 years and the engine has been through multiple changes.)