Ported Kaase Boss Hemi heads - flow test

Aaron from Oz, these are your numbers. I would like to sincerely thank Dave Freelander for flow testing these heads at the shop, this weekend while I was out of town. For those of you who don't know, flow testing the Boss Hemi heads is a big job, because of the fixturing you have to go through.

Intakes; average of all 8, using the Kaase 2.300" valve and his valve job.

.100-73.5, .200=162.8, .300=276, .400=355.6, .500=409.3, .600=432.1, .700=429.8, .750=429.6, .800=428.4 cfm. Notice that we had all the flow we were going to get by .600" valve lift. I believe at this point we are limited by the curtain window of the valve, and that with a bigger valve such as 2.400" we would continue to climb, in regards to our cfm. Before we put a 2.400" valve in the Kaase heads, I need to do some investigating in regards to valve seats and etc.

Exhausts; average of all 8, using the Kaase 1.900" valve and his valve job. Exhausts are flowed without a pipe.

.100=52.5, .200=126.8, .300=182.4, .400=245.6, .500=282.3, .600=307.5, .700=313.1, .750=314.1, .800=314.8 cfm. Notice that we essentially had all the flow we were going to get by .600" valve lift again. In regards to the exhaust ports, I believe at this point we are limited by the port shape/design. Primarily by having the "factory" low port exit.

Jon is to be commended in regards to these heads. His own self imposed restriction was to keep the port entry and exit in the stock factory location. I have seen the Roberts Design IHRA Pro Stock Hemi heads that Jon uses and they have an excellent combustion chamber shape. It's almost like a hemi shape around each individual valve. These new Kaase Boss Hemi heads, have many of the same features as the big IHRA head in regards to combustion chamber shape, therefore I believe the Kaase combustion chamber shape is better than some other Ford Hemi heads that I've seen.

Hope this is interesting,

Charlie Evans

It is Charlie. Keep it here!
Regards.
Al

Thank's Charlie for posting that info.

Kieth

Impressive numbers, Charlie, thanks for posting them. It will be interesting to see what they will do with the larger intake valve.

Please be gentle because Im about to ask a very stupid question...

Would one expect a > or = .600 lift cam to perform better with these heads as tested than say a similar duration .600+ lift cam with all other factors being similar or equal?

CFM peak at .600 would seem to make the motor lose power above that lift point.

Just because the flow flattens out doesn't mean thats where you stop with the cam Lift.

Thanks for the Post Charlie! We always enjoy reading your Tech articles !!

WOW!! Charlie...

another outstanding job as usual.. and also Thankyou.. Dave for spending hours of your time flow testing my heads...charlie i'm surprised that these boss9 heads beat my max ported (by you) 2.300" valve p51's in the lower lift ranges under .500"

as all you guys here know.. there totally different animals.. but its interesting.
Charlie if you don't mind could you post out of the box ..Kaase boss9 flow numbers to compare to these?

Anyways hi to everyone!!

i'll post my pump gas street/strip build as it comes along and dyno test in the future..

cheers to you all Aaron..

Aaron welcome to the site ..... can you please post details of the car in your avatar its sweet bro

Aaron from Oz,

I did NOT baseline flow your particular set of heads out of the box. However, a little over a year ago, we did flow test some out of the box Kaase Boss Hemi heads. Those flow numbers were as follows.

Intakes;
.100=75.3, .200=161.5, .300=240.8, .400=322.8, .500=373.8, .600=392.3, .700=393.3, .800=390 cfm.

Exhausts;
.100=53, .200=127.8, .300=206, .400=253.8, .500=276, .600=293.5, .700=302.8, .800=307 cfm.

Hope this helps,

Charlie Evans

IcallhimGeorge wrote:Please be gentle because Im about to ask a very stupid question...

Would one expect a > or = .600 lift cam to perform better with these heads as tested than say a similar duration .600+ lift cam with all other factors being similar or equal?

CFM peak at .600 would seem to make the motor lose power above that lift point.

Kris and George,

The lift can keep going higher but the only benefit is more duration, you can gain more "area under the curve".

Bill

when i bought it 16 years ago it was..a lime green poverty pack.. 3 on the tree 250ci 6 cyl 1973 ford falcon coupe.

me and my brothers built a replica inmo ..of one of OZ's best muscle cars.. XA GT 351 Cleveland falcon coupe.. we painted it violet purple very close to the factory option colour.. it was running a pump gas 501ci BBF with eldebrock heads etc..506rwhp.. on a dyno jet chassis dyno.

since then we've built a pump gas 562ci with charlie's ported p51"s,.. a Randy Malik custom mild-ish street/strip solid roller.. it made 788hp at 6300 on a engine dyno.. but we haven't fitted it yet EVERYTHING needs beefing up to get the best out of it..then jon brings back the boss9's so its engine time again..

cheers to ya Aaron..

Aaron from Oz,

Where do you want me to "land" in terms of combustion chamber volume? I'm getting 89.5 cc's now.

Thanks,
Charlie

charlie..
EDIT...found the piston spec paperwork when i got home from work.. 88cc give or take a little will give me what i'm aiming for 10.5 to 1 comp...so ignore the rant..i wrote on my lunch break

cheers Aaron..
i'm coming up with 88cc for 10.5 to 1 comp on daimond pistons site calculator..

combo 4.500 x 4.560 bore
.oo5 down the bore
4.670 gasket bore
.041 gasket thinkness
-24.5cc dish piston
.350 top ring up
88cc chamber
does that sound about right to you?

boss9coupe wrote:charlie..
EDIT...found the piston spec paperwork when i got home from work.. 88cc give or take a little will give me what i'm aiming for 10.5 to 1 comp...so ignore the rant..i wrote on my lunch break

cheers Aaron..
i'm coming up with 88cc for 10.5 to 1 comp on daimond pistons site calculator..

combo 4.500 x 4.560 bore
.oo5 down the bore
4.670 gasket bore
.041 gasket thinkness
-24.5cc dish piston
.350 top ring up
88cc chamber
does that sound about right to you?

Aaron,

Yes, it does. I think I need to give them a thin shave, like .007". Is that okay with you? Let me know ASAP.

Thanks,

Charlie

Charlie ..

just wondering have you had a chance to cc the intake runner volume on the boss9's?

if not could you cc the intake runner on my heads please when you get a chance? just curious ..not that it matters much as jon said.. they make pretty good "poop" down low even on a 429 cuber..

Thanks Aaron..

Yes Aaron,

I measured a couple of them today. They are 314 cc in volume.

Hope this helps,
Charlie