Not sure on the on screen numbers. I took a screen shot of a video my Dad took, and sent me. Not sure if the video is of the same pull as the dyno sheet? That might be the video when using the 750? Either way, with all the dyno sessions I’ve been to now, what comes up on the screen, and what is on the printout always seems off? I’m no expert, so I can’t explain that.

The numbers on the screen can't keep up in real time.

Great results! Nice work

Yeah Chip you're right 100% seen that many times it's like the HP and TQ flash at almost random intervals during a pull.

Was any head or intake porting done for that motor? Still amazing power and especially impressive torque.

Now that I remember about 17 (correction: it was 1997 27 !!!) years ago I built a 426" 4.03"B x 4.175"S for my Cobra with some deep ported Trick Flow Windsor heads (when they first came out and before all the big port CNC heads they have now) and it made 511HP and 522TQ with a 232/237 @.050 540 lift Hydraulic flat tappet.

I guess thats not really that far off HP+TQ/ci from this combo in terms of compression, head flow and cam timing. It's still running (I just had it out this weekend) and it has that same wall to wall torque powerband. Shift at 3000 or shift at 5500 it's the same 'shove in the back'. Makes it really fun to drive, You're Dad is going to have so much fun!

It’s a test to see if you’re really paying attention.

LOL Fast!

I've always looked at power not only in terms of comparative Port Flow/Velocity (getting the air/fuel in and out) but also in terms of how efficiently that air and fuel combusts! (once it's in the hole).

That's part of why I thought with the Edelbrock valve angle, straight-in plug placement and just an overall 'so-so' wedge combustion chamber, Being able to pull out 1.2 hp/cube (with that relatively small cam) was a really Nice surprise! That's power in a 450-ish sized BBM you would think would take something like a 238/244 @.050 520.540 lift Hydraulic roller to get to.

No porting has been done to either the intake, or heads. These are the same heads that have been on the car for the last 20 years. Same valve springs as well. The heads did get a good valve job this go around, and some cut off, to maximize the compression ratio.

I had no idea it would go as high as it did. I thought MAYBE 490hp? I never once worried about the numbers though. My main concern for running it on the dyno, was to get everything dialed in, and make sure it wasn't leaking oil all over the place. I am vary happy with the torque curve though. I'll have to post a picture of the HP/Trq curve graph.

Guess the cam didn't suck after all...

It’s horrible!

I'm still amazed at how efficient this motor is at making torque.

BTW you said you actually used the those VERY NICELY SHAPED Chassis headers on the DYNO ........THAT's really the Difference between what everybody guessed by vs what you actually ran!! And where that "extra" 484 magic HP and torque come from!

And why everybody guessed "kinda right" but low. So If we add 25-30 tq/hp to nearly everyone's guesses most of us were actually pretty close.

My guess is you may need to jet down just a tad once you're driving the car.

I live in NASCAR country...and for years the P9 Dodges made way more power on the dynos than they actually could in the car because to fit the chassis they couldn't get those first few extra straight inches right off of the flange.

Calvin Elston (who is very well known for his headers) said the chassis fitment compromises cost the Dodge teams close to 50hp

anyway...

The 3.90" strokes really seem to have a 'sweet spot' in the 9.98" low decks....and a huge part of building and holding onto torque (especially past the TQ peak) is keeping the internal friction losses to a minimum....maybe that stroke and rod ratio and piston pin height are just a 'sweet spot' for BB mopars.

I was always fascinated how several 455" Buicks just made massive torque too....again 3.90" stroke. A lot of the LS stuff seems to favor using 3.9 vs 4.,0 strokes too.

JericoGTX....where did you degree the cam ICL? And was there anything special about the Pistons? (dome/dish/ring pack?) I'm guessing you used something like a 6.700-ish BBC rod and the same 1.32" CH, .990 pin.


Any pics of the short block and were you zero deck? I like mine about .005" out of the hole.

I'm thinking of a 3.90 stroker low deck with a zero deck dish, TF 240's and a turbo for my next project. I'm torn between using a 383 for the smaller bore (more HG sealing surface between the cylinders) or the stronger webbing of a 230 block.

Thanks!!