Nice numbers!

It will be interesting to see what happens to your boost numbers with these heads. I'm discussing tunnel rams with two other members that have the M4 dual carb setup. Better manifold than the Offy dual quad that comes with the kit, and it makes room for a tomcat intercooler setup. Are you sure you can't put a scoop on your boat?

Jimv,

From the last post, I am wondering if you could give me some basic flow nubers from a stock 502 mpi head (990 rec port) and a dart 355 cnc head. I'm just looking for neighborhood values to use in dyno 2k..

Brad Perry


Here are some numbers from a 188 casting bone stock 28" The ports are similar to the 990 casting


Lift......CFM............CFM Exhaust

.2........148............101
.3........213............135
.4........250............162
.5........287............176
.6........317............182
.65......323............184
.7........328............186


This is the right hand port. The left will be down about four percent. Sorry I dont have airflow numbers for a cnc'd Dart head.

Mark

I will dig out the numbers and post them.


Bobby Daniels,

How's the AFR numbers comming?

JIMV,

Are those "188" numbers with an exhaust pipe? Looking at numbers from Chevy High Performance, your numbers are higher than their casting. I don't remember what inches they flowed at. Do you have any numbers on a ported set of these heads? My set is bowl ported, gasket matched with 2.25 intake and 1.88 exhaust. I don't have flow numbers for these. Just curious.

JIM V. I should bring you one of my heads and let you post those #s.

Washed away

The exhaust numbers are without a pipe. Check the valve sizes, I used a eaton/manley valve 1.880 on the exhaust, 219 intake. I will try to find some flow numbers on a full port LS-6 and post them.


Tinkerboater if you have a head off maybe we can flow one of yours. Thanks JimV

JimV

HPC's used stock valve sizing for testing. Will be intrested in those numbers to run thru the desktop dyno.

Isn't it true Jim V that the reason to stay away from the GM versions of the BBC heads is that it is very difficult to get flow from the exhaust, becasue of the nonraised port. For stock heads those intakes are fairly impressive.

Turbojack,
Are these the AFR 335cc CNC'c heads? What size intake valves? and your post is a bit confusing, you have two sets of numbers. I make the assumption that the first set of In/EX are the measured numbers and the next two colums are the advertised numbers from AFR? Is this correct?

Thanks

Dick