Does anyone have any experience with the ProMaxx big block heads? I bought a set for what I thought was a great deal. They were used on a dyno mule while the guy was testing cam and intake combos... For $700 it was hard to turn down. I'm just looking for some feed back on these before I bolt them to my 440. Is it worth investing any money on porting?

Thanks

The easiest gains on port work are the first port & bowl clean up, so yes, i would at very least tidy up the bowl & valve stem & the turns before screwing them on. Nth degree porting looking for every cfm??? nah, dont waste your time.

They look like a low cost aluminum head.

Here they are...

https://promaxxperformance.com/product/maxx-210-bb-mopar/

Depending upon your performance goals and application, there can be some worthwhile gains from porting those heads. It really matters on what you're building and your budget as to whether it makes sense to do it.

I'm upgrading the current 440 thats in my 72 Duster... Cam choice is still undecided but I am looking at the Comp XE284 but I plan on giving the guys at Hughes Racing a quick call today. I should be at 10:1 with the 84 cc heads, I may take .030 off them to bump up the compression a little more. I will likely spend the time or money to clean up the ports for a good gasket match and maybe some bowl work. I'm trying to get y duster in the mid 11's with as much of the current parts I have now including the new heads and unchosen cam. The chassis is pretty fresh with SS springs and pinion snubber in the rear and with 318 T-bars and Comp Eng. shocks all around.

I am in the process of going over my new Promaxx Big Block heads before bolting them on. Just quick "shade tree" techniques for checking guide clearance, valve seat concentricity and upgrading to beehive style springs and retainers. I'm giving the valves a quick "lap in" because I was able to see a little bit of daylight between a couple exhaust valves and their seats under close inspection. All in all they will be a huge upgrade over my 906's.

Remove the pinion snubber any time your using SS leaf springs, they are not compatable

If you can see light in between the valve and seat, do yourself a favor, and go have the valve seats cut properly. if you can see light, there is too much run out, and you cant " fix it" properly by lapping them.How do you plan on doing a shade tree ( I understand you are probably trying to save money) runout? Get a good valve job, its worth every penny.A good valve job cant be done without the valve guides sized right as well, it all goes together. My 2 cents.

I agree , I'm taking a risk not having these heads checked over by a shop. Hopefully It won't bite me in the ass. We shall see.

I buy WD40 buy the gallon so I like to put a set of heads on my head stands with the valves up and assembled. I then fill each chamber up with WD40 to check for leaks. Just a quick way to double check things and less clean-up than water.

After lapping the valves they pass the WD-40 test.. not a drop leaked. all the valves bounce off their seats indicating a concentric valve job as well. All the guides "feel" within spec.. i.e. ever so slightly loose when dry in the guide.. then after a few drops of 10w-30 is applied to the guides the "wiggle" is gone. I am upgrading to 10 degree locks and retainers as well. Along with the properly sized beehive springs.