1970 Dart 340/416 Stroker build help

[Mean416]

Im gonna sing a different tune here. Guys not every engine needs to be a drag engine. Is it flow limited? Sure. But every engine Mopar ever made - that wasn't a hemi - was flow limited.

This combo probably runs really well for a street car. Probably tops out around 5000-5500 rpm.

If you start bumping up the duration past the 220s you're gonna need to go way up in stall and gearing. Just depends on what the op actually wants.

Those rocker arms will take more that you might think.

 

[middleagecrisis]

Make sure your secondary throttle blades are completely shut. I’m betting they are cracked slightly open. You’ll have to take the carburetor off to really know and access the adjustment screw. It happened to me on a carburetor that I had rebuilt by a business years ago.

 

[340sFastback]

Did you check timing curve? What is initial and total timing set at?

 

[furrystump]

The only thing I would offer is if the X heads are untouched, don’t learn on them. Numbers guys like to pay for them. Also silly people like me. If you pursue porting the heads, it would probably be cheaper and better to go aftermarket aluminum. If you REALLY want to run a cast iron head. (Uggggggggg ) There is a guy around Ohio? who has a CNC program for them which would give you a pretty good start. Can’t remember the name. That being said Dwayne (PRH) did my X heads, but porting cast iron sucks!