Edelbrock STR 12 340 intake.

Id like to find out if anyone on Mopats is running a STR 12 crossram on their 340 to find out how it works. Ive been told by many people that they never worked right due to a bad design flaw . Unburned gas sits in the intake and has a tendancy to blow up and damage the lid cracking it on start up . Is this true ?. its a cool looking manifold and seldom seen on 340s. Any info on this intake would be helpfull id like the good and the bad on this cool peice how it works if it can be modified to be reliable etc, thanks Moparts for the post its a great site.

LAR414 has one on his 67 Dart, he modified it a small amount and claims that it runs great. He'll post on this I'm sure.

I believe LAR_414 went back to a single plane and single 4bbl for now. Had a low speed bucking problem when he installed the 4 speed. Said he will put it back on and play some more once he fine tunes his shifting skills at the track with the single. Ran great, he said, with his auto. Looks killer too! He did have to do some popsicle stick tricks in the runners.

I ran one. Worked fine, but I had a pretty mild 284/484 purple cam. I had a custom 1/4 AL plate dual 4 top and buckled it on first start up (my fault, crossed 2 spark plug wires) did a 3/8 single 4 top and worked fine. Softer than my Strip Dominator down low but beat it up top. No popsicle sticks in mine.

I thought there was some kind of pressure relief valve you could install on those intakes to vent the excess pressure? In the event of a backfire the pressure vents instead of killing your intake.

Yes, you can install a pop off valve into them and prevent from breaking parts.

As Jeff said, I ran the single 4 over the summer to tune it up sweet as well as get used to my new Stick shift at the track. Got things pretty squared away. Got a better handle on my low speed bucking problem, and it's NOT the intake or carbs. More of a camshaft / ignition timing issue.

Anyways, I'm having fun making even more mods to my STR-12 and it will be on the car over the winter. It's going to run better and look even nicer. Re-doing linkage, routing of stuff, making spring loaded pop of valves.

Here's a pic of it from a couple years ago on my Dart

I have a 440 with an edelbrock str 14. my engine builder did have some problems he described as puddling which he resolved by changing jets.It is a real vintage manifold,The end result for us was 460hp and 517 fp torque.

Looks good polished,what did you use?

mothers.I also used an eastwood clear coat and baked it in my wife's oven.

here's another pic...on the dyno