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MILD THUNDER 06-22-2016 09:51 PM


Originally Posted by getrdunn (Post 4452404)
I only mentioned finished runner size for those who may be curious. I wandered off a little from my original post. And yes I do understand flow and velocity. Been at it a while and worked along side valako and flowed many heads including some of my own. Thanks to my thread my builds have now slightly changed. Tks black baja for putting my original plan back in motion.

I was just mentioning it, as many read these kind of threads, and think runner volume is the deal maker, or deal breaker, on a build, and it simply isnt that cut and dry. I was not aware of your cylinder head backround, just going off what I read from posts. I was assuming by your posts you were insinuating that since the heads have been opened up from 310 to 320cc, it should have some effect on the build result/design.

Interesting transition though. We have moved on from a dual plane intaked 565, to tunnel ram setup! I like it . :)

getrdunn 06-22-2016 10:25 PM


Originally Posted by MILD THUNDER (Post 4452430)
I was just mentioning it, as many read these kind of threads, and think runner volume is the deal maker, or deal breaker, on a build, and it simply isnt that cut and dry. I was not aware of your cylinder head backround, just going off what I read from posts. I was assuming by your posts you were insinuating that since the heads have been opened up from 310 to 320cc, it should have some effect on the build result/design.

Interesting transition though. We have moved on from a dual plane intaked 565, to tunnel ram setup! I like it . :)

I get it. I kinda generalized my post with who was posting and pretty much figured you knew apprx where my flow numbers would be. The heads aren't really my first choice but already have them. regardless the end result is the ports end up with a shape of their own. Not round, not rectangular, not square, I was testing the raised floors back in valakos epoxy days. 1988/89. Much improved since then. I really did wanna keep it simple with single plane and Dom but won't be the first time I changed a build. Originally I was going to go with oval port afr 300's. To this day they spark my interest on a larger CI build. If I end up with an honest 700-725 plus at 5,700 I will be content. :ernaehrung004:

SB 06-22-2016 10:43 PM

Raised Port Oval 24*

BP BB-3 XTRA O 332
(CNC Ported/
50° Valve Job)
2.300 Intake
153
231
300
354
396
424
425
428
1.880 Exhaust
130
177
239
278
284
290
295
297

endeavour32 06-22-2016 10:55 PM

Your heads will indeed be 320’s after Jim does his port work to them. As you also know this will include welding the floors and modifying the runner shape and when all is said and done the intake will be 320 as you have stated.

Your heads will flow the same as mine and if Jim didn't give you the flow numbers here are the numbers from my Valako Pro 1’s.

.20 149/130
.30 225/171
.40 295/206
.50 348/256
.60 380/286
.70 394/300

Your heads will easily support the power you are going to make and are with within a few CFM’s of the AFR’s thought the entire range. I agree it would have been interesting to see what the AFR’s would have been capable of, but I doubt they would have made any additional power.

So did I read it right- are you going to go with tunnel rams on your new engines?

Black Baja 06-23-2016 05:01 AM


Originally Posted by SB (Post 4452446)
Raised Port Oval 24*

BP BB-3 XTRA O 332
(CNC Ported/
50° Valve Job)
2.300 Intake
153
231
300
354
396
424
425
428
1.880 Exhaust
130
177
239
278
284
290
295
297

That head works very well with a tunnel ram on a 540 with a pair of Dominators. 850hp @ 6300. This is with a .800 lift solid roller. Single plane intake same cam 800hp. And lastly with a much smaller hydraulic roller and 4150 carb 750hp @6300 rpm 540 cu in.

I'll throw this out there also when you spend $4000 + on a fully cnc'd heads from AFR or Brodix you end up with a set of heads with a crap valve job on them. Brodix's valve job a little worse than AFR's.

SB 06-23-2016 06:10 AM

In case anyone is ever interested, HVH has a raised oval port Brodix head that is around 300-305cc's.

I have the flow #'s somewhere, but in meantime , here is a pic. You can see how far the runners are raised.

http://image.superchevy.com/f/100889...ntake_port.jpg

Compared to normal oval port location

http://www.brodix.com/wp-content/gal...b-o-intake.jpg

MILD THUNDER 06-23-2016 06:25 AM


Originally Posted by endeavour32 (Post 4452449)
Your heads will indeed be 320’s after Jim does his port work to them. As you also know this will include welding the floors and modifying the runner shape and when all is said and done the intake will be 320 as you have stated.

Your heads will flow the same as mine and if Jim didn't give you the flow numbers here are the numbers from my Valako Pro 1’s.

.20 149/130
.30 225/171
.40 295/206
.50 348/256
.60 380/286
.70 394/300

Your heads will easily support the power you are going to make and are with within a few CFM’s of the AFR’s thought the entire range. I agree it would have been interesting to see what the AFR’s would have been capable of, but I doubt they would have made any additional power.

So did I read it right- are you going to go with tunnel rams on your new engines?

I would guess those numbers are flowed without a pipe on the exhaust too? It be interesting to see the numbers on the afr, flowed without a pipe on the same bench.

endeavour32 06-23-2016 07:23 AM

Yes Joe, that would be correct- no pipe. I would agree, I would also be interested to see how the 300 AFR's flow on Jim's bench. Getrdunn- has Jim ever flowed the AFR?

getrdunn 06-23-2016 10:25 AM


Originally Posted by endeavour32 (Post 4452505)
Yes Joe, that would be correct- no pipe. I would agree, I would also be interested to see how the 300 AFR's flow on Jim's bench. Getrdunn- has Jim ever flowed the AFR?

No believe it or not he hasn't. Talked with him this morning. He's gonna get back with me today and get some other heads coming. We had a lengthy conversation but interesting to say the least.

endeavour32 06-23-2016 05:51 PM

So are you going to be using something other than the Pro 1's?


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