Another Thumperdart Success.....572 Hemi Sized (pics&Vids)

Well, I probably am leaving out some details, but a friend of mine built a similar engine as mine....And asked if would come down and watch it being dyno'd....Of course I said yes, and brought my Thumperized 1250 Dominator to try if we had time.

Build specs:
572 Hemi
Eddy heads
Solid Mechanical 283 dur @50 .680 lift
9.5:1
World Block
Intake....Depends! But probably a Six Pack.....Yeah, Sixpack Hemi!

-We tried a heavily modified six pack on a Modman intake first...This is Rob's engine, and for anyone who does not know him in the Mopar circles, he IS Mr. Six Pack.....He has been racing these six packs on Wedges for so long, I don't think he could help himself and built one for the Hemi. I was very glad he went with the Modman intake on this build as well.

-First of many pulls was with the sixpack...Lots of tuning went into it on a basic run in stand with an AFR gauge before the dyno, but without a load, its tough....

Best pull with it was 741hp & 666ft/lbs....lots of tuning to get it there. Still needs work as the transition was blubbery with the vacuum carbs coming in...I prefer to run three mechanicals over anything vacuum, but I am sure he will figure it out.






Vid.............:
https://www.youtube.com/watch?v=ueC_4nAdSZ4&feature=youtu.be


Next was the Promax 950 Dyno mule carb he had....Not sure what was done, but we made a bunch of pulls with it changing air bleads, timing, etc and netted a best of 749hp at 704ft/lbs...





Vid.......................:
https://www.youtube.com/watch?v=5QjkTW-o1QY&feature=youtu.be



Now we get to my 1250 G3 Holley that I had Thumperized.....Now it has not had fuel in it since the conversion....It was a 3-circuit and I could not make it work on my 605...Had it converted to 2-circuit, and never touched it!

Fired right up to a perfect idle, and then mad 779hp & 717ft/lbs of torque....No adjustments other than floats....





Vid......................:
https://www.youtube.com/watch?v=M5l_w8n8gbE&feature=youtu.be


Thanks Mike at Jan Cen Racing and Rob Brooks for inviting me....

Very nice!

Very cool piece. Way to go, Dom!

Not sure if anyone on here has heard of Jan-Cen Racing or Mike Janis, but those guys are Pro Mod gurus....I saw so many high end blowers and Hemis today all over the shop....Amazing.....

Here are a couple more pics....




************************
A torched Seal 4-Good Exhaust gasket from Rob's motor on the run in stand...Ironic really!*********************************

No stageV intake and dual carbs? Or the Eddy intake with duals?

Ahhh No....You forgot to lend them to us...Still waiting!

Thank you so much and glad it worked out for you guys..........

Now that sounds like a fun dyno day

Nice numbers on a low CR too !!

Did they do anything special for the exhaust relief on the pistons for the edelbrock heads' different exhaust valve angle? Or was the compression height low enough to make it a non-issue? Awesome motor, box stock head castings or ported?

NICE!

My block is there right now..lol

The eddy heads caused major issues for Rob and how they fit up with the pistons....I know he had to have the pistons re-done multiple times due to the newness of the heads, and ultimately, I think it contributed to the lower compression than what his target was.

Predictable results from the selected carb and manifold combinations. Six Pack was actually closer to Dominator than I thought it would be. Would have been interesting to try single top on Mod Man, just to see results. But would only be a research project as doubt anybody would use one for that

I actually thought the Dominator was too big for this motor, but I had it sitting on the shelf waiting for my 605 to be finished up. AFR on his motor was right around 12.7-13.0 and he used ethanol free fuel. So it seemed right in the ball park and we just left it that way.

What you can't see is how bad the six pack was where the outboards opened in the mid range. The AFR jumped all over when the opened. A couple of the pulls it was real noticeable. I do not have a copy of the dyno sheets, but you might be able to hear it in the vid. It stumbled every-time. The more we messed with it, the more it seemed to get a tad worse. First pull was the best. And the engine was the coolest. Bringing it earlier seemed better. It did make the Hp though....I would loved to have tried three center carbs.

No way the Dominator is too big for a motor that size

I`m w/you, maybe 2 1050`s on a sheet metal intake.......

I know Mike very well.. surprised you didnt jet up
on that 1250... all in all a good day on the dyno
congrats

Bump to keep from being bored...

I always felt that six packs were better suited to wedges due to port arrangement and 2 fours better suited to Hemis.

Just my 2 cents...Joe

I've never gone wrong(within reason)going to a bigger carb on just about everything I've built or tuned for others over the years and have always prefered single carbs as well on most stuff. Never use vacuum assisted carbs and can make a DP work on just about anything.........

Can you build me a 1450 3 circuit with vacuum secondaries? I'm looking to get max power out of my slant 6.

Coming right up..........

How bout an 8 pack

That's what YOU NEED not the "BIG" 2-Pack...........

Eh,it all goes in the blender

Ya but I like to sip my drink not drown in it..........