Poly Stroker Dyno Numbers

[TopBanana]

Just recently finished building a 392 Poly Stroker.

Final numbers from the dyno are...

405 HP @ 4900 rpm
472 LB/FT @ 4100 rpm

 

[Belle66]

Beautiful! That torque monster will get some good 60 foot times. Is that going in the Coronet?

 

[Dako]

I love it!!

 

[TopBanana]

Beautiful! That torque monster will get some good 60 foot times. Is that going in the Coronet?

Yes. With a Frank Lupo Dynamic 3500 flash convertor and 3.55's behind it, it should get out of it's own way!!!

 

[lewtot184]

sounds like a cool build. we need engine details!!!!!

 

[TopBanana]

Recipe is pretty simple...

318, .040" over + 4' stroke = 392 CI.

9.5:1 custom pistons, .470 Racer Brown cam, 4" stroke Eagle crank, Eagle I beam rods, new Chrysler Power intake, 1.95/1.625 valves, 750 CFM Quick Fuel carb

Here's a photo of it on the Dyno...

 

[Greg Ducato]

Congrats, those are great HP and TQ numbers for a street car, I'm glad to see these engines getting some attention

 

[Blackheart]

Great to see, almost the same build as mine but I'm at 9.75 to 1, .060 over (396 CI), Eagle 4" stroker crank, Eagle rods, Racer Brown ST-14 cam, Ross pistons, haven't fired it yet, but love seeing your numbers, have been hoping for somewhere between 375-400 HP for mine.

 

[TopBanana]

Dyno it!!!

Great to see, almost the same build as mine but I'm at 9.75 to 1, .060 over (396 CI), Eagle 4" stroker crank, Eagle rods, Racer Brown ST-14 cam, Ross pistons, haven't fired it yet, but love seeing your numbers, have been hoping for somewhere between 375-400 HP for mine.

Nice combo! He calls mine cam an ST-232, .470", 232 deg @ .050", 108 LC

With the experience I had, I would HIGHLY recommend that you dyno the motor for break-in and tuning PRIOR to putting it in the car. The part of the story I DIDN'T tell was...I had a rocker back off and it bent the #6 intake valve. We pulled the head and discovered that the pistons had the fly cuts cut in the wrong location. Before anyone asks...no, I stupidly didn't check piston to valve clearance, but if the pistons were done correctly, I wouldn't have had to. Long story short the other 7 intake valves were bent slightly too. The engine had to be completely torn down to re-fly cut the pistons, cut a new valve, and straighten the other 7. The dyno shop did it all tear down, repairs, and re-assembly right there in 1 week. Jim Bowen Racing Engines (the dyno shop) was an absolute savior in this situation! I would recommend him to anyone and would him in a heartbeat!!!

 

[66coronet500]

Have you done any measurements for hood clearance yet?

 

[TopBanana]

I think these pictures say it all. (I have to give Ricky Hall form the 62-65 Mopar List credit for this photo)

 

[63Fury*]

what did you do to the heads?

 

[threewood]

I think these pictures say it all. (I have to give Ricky Hall form the 62-65 Mopar List credit for this photo)

View attachment 247057View attachment 247058View attachment 247059

That is great to know. I love the poly and built mine with stock stroke crank. I am running the factory 4bbl intake for now as I didn't see any specs listed for the chrysler power intake. Does that intake have bosses for factory throttle bracket and a vacuum port to run the heater in the cabin?