Some of you know I sent one of my Chapman 285cc Max Wedge Stage VI's up to Dwayne, he sent me back the numbers. I'll wait to see if he chimes in with some Commentary.

Thats cool... make us wait

i wish i knew he had those when i was talking to him earlier today. fess up wize, what are the numbers. don't make me write up a new bill for that crank, LOL.

C'mon now, where's the numbers?

I still have the numbers from my antique stage VI heads that Dwayne did. It will be interesting to see how they vary.

OH great, now i'll be sitting here ALL night waiting for the #'s.... thanks

OK...here goes straight from Dwayne's E-mail to me this evening:

Lift" I/E

.100 72.5/58.2
.200 153.7/118.6
.300 224.3/178.2
.400 285.2/218.2
.500 329.6/232.8
.600 361.9/245.1 (edit-read wrong column)
.650 368.1/249.9
.700 364/253.1
.750 364/254.7
.800 364/256.3

Through .600 lift they are dead on (within ~1% either way) with Chapmans website numbers published here:

http://chapmanracingheads.com/p_Specification.asp?ID=80

It's nice to see "Real" Moparts numbers off of "Our" bench, makes me feel better about them that they've been flowed by Fast Hisself

I asked Dwayne why they apparently "stalled" at .700 especially when they were still slightly climbing from .600 to .650; On the Chapman bench they apparently peaked at 381 @.750. I'm not going to be running a cam much bigger than ~.680 but I'm still curious about that.

I have the other one and I must say, they look really nice, Kinda reminds me of a scaled up last gen SBC NASCAR head.

They seem to be....adequate

Anyway...there ya go!!

Nice!! Those ought to run good!

Sweet mother of all that is unholy!!! Now that some flow.

Those #'s make my ported Ebrocks look like a 2hp briggs-stratton head.

P.S. thanks 4 not making me stay up all night waiting.

Looks awesome to me, my whole 360 engine could breathe from one port

Bobby, those heads are way too big for that cam. i think you need to send those down to me and i'll send something back that'll be more useful...no point in wasting a good set of heads...

Dan,

Gosh, that's awful kind of you, buddy <sniff!>

Just give them to me . I will be your friend

The funny thing is...I'm Hoping Dwayne can Elaborate, But the ports don't really look THAT BIG, The Indy-1 is Noticably bigger in total area and I've seen several SR's taken to bigger than this 285cc's. The exhaust looks like nothing special at all EXCEPT that both ports have WAYYY better short sides than anything I've seen on a Big Block Short of the B1. Again it looks to me very much like the pre SB2 NASCAR SBC port shape...only proportionally bigger. You really don't notice it at first glance but when you really start looking at the roof to long side turn it doesn't bottleneck the port like a standard VI.

Dwayne said he wanted to take some measurements.


By the way, a big thanks to Chuck Millen @ Best Machine, I know he tried and tried to get MP to get us some valves, really hoped to get numbers off of Both Benches before he sent them to Dwayne.

Wise, those intake numbers are almost a mirror image of my 440-1s!! Very good flow numbers for sure. R&J that did mine are among the best in the business , so from my point of veiw, you have a dynomite set of heads there. My runners are 365cc, so you have more velocity for a bit wider powerband?
The only differance in flow numbers came above about .500 on the indys, they keep on climbing to 301 cfm at .800. But that may very well be useless, with most everything happening in the midrange lifts anyway. I will be looking for a dyno post in the near future!!

What size bench does Chapman Flow on, and what is Dwayne using these days? I do recall Dwayne telling me ages ago, but I can't remember everything, lol. I do recall Dwayne's bench being conservative regardless.
AL...

wow wize,nice numbers...you oughta make some serious steam.....those heads flow almost as well as my buddies w8's that best machine is finishing up the motor for.........you should have 800 horse potential with those baby's!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

I wonder if Dwayne will try putting a 2" flow pipe on the exhausts just for grins, Steve Dulcich got like 301!


Looks like a single pattern cam might be in order!!