Opinions on SBC intakes

[Scotthatch]

I think the afr 245 will do ok, I would think if he isn't turning it over 7000 RPM he needs get them to flow 345+ cfm at lift. he can maybe stretch it to 7500 with 355 cfm

If he gets them to flow any more it will make less power.

He needs to slow them down and increase the cross section (gasket area).
How many sets of these heads have you used? Out of curiosity.

October 11 2013 12:56:33 PM
OCT11012.SFD
Dyno Test# 12 with old Edelbrock #2970 Super Victor
Peak TQ= 578.1 at 6500
Peak HP= 815.8 at 8200<<---- this is with only 322 CFM @ 28" inches

If he gets them to flow any more it will make less power.

... ... i see someone is catching on

355 CFM should make less HP ..at best => no difference in HP

would need to weldup the AFR's Pushrod Pinch area + Offset Rockers + Lifters to make higher RPM HP than 8000-8300 RPM Range
and to effectively use more than 325 CFM

317 to 325 CFM ... is all you need to make 800+ HP at 8000 to 8300 Peak HP RPM Range
that will run low 8.30 to 8.40's second ET's at 162+ MPH in 2450 lbs Berretta

What you are leaving out is that it's going to take a roller cam that is like 290 to 300 degrees at .050 to make that number and what you are doing is keeping the airspeed up to deal with the late closing of the intake valve

[maxracesoftware]

What you are leaving out is that it's going to take a roller cam that is like 290 to 300 degrees at .050 to make that number and what you are doing is keeping the airspeed up to deal with the late closing of the intake valve

285/311 @ 0.050" will work 116 to 118 LSA's

it has a ton of AirSpeed at 325+ CFM or 355 CFM ...
355 CFM in that Head will kill hi RPM HP

... you want slower Airspeed instead ... along with a great Port Shape
the FPS thru the Pushrod Pinch and over the Short Turn Apex will be way too high on the AFR 245's at anything over 315-320 CFM
to make Peak HP at 8000+ RPMs

without the proper Port FPS + CSA + Shape .... it won't make anymore HP if you increase CFM past 317-325 CFM in those Heads

take the AFR245's on that 440cid and Dyno test it
see if it can really make its Peak HP at 8200-8300 RPM like a Dart Pro 1 or Brodix Track 1 ??
then go to the Dragstrip and see how fast it runs ?

[user-17438]

What you are leaving out is that it's going to take a roller cam that is like 290 to 300 degrees at .050 to make that number and what you are doing is keeping the airspeed up to deal with the late closing of the intake valve

285/311 @ 0.050" will work 116 to 118 LSA's

it has a ton of AirSpeed at 325+ CFM or 355 CFM ...
355 CFM in that Head will kill hi RPM HP

... you want slower Airspeed instead ... along with a great Port Shape
the FPS thru the Pushrod Pinch and over the Short Turn Apex will be way too high on the AFR 245's at anything over 315-320 CFM
to make Peak HP at 8000+ RPMs

without the proper Port FPS + CSA + Shape .... it won't make anymore HP if you increase CFM past 317-325 CFM in those Heads

take the AFR245's on that 440cid and Dyno test it
see if it can really make its Peak HP at 8200-8300 RPM like a Dart Pro 1 or Brodix Track 1 ??
then go to the Dragstrip and see how fast it runs ?

Exactly make em bigger and slow them down! I'm glad Larry agrees with me. Just wish so many other would.

[Walter R. Malik]

In the past, with a large smallblock Chevy engine using a Dominator carburetor, I have had very good luck with using the BMP 061050 s.b. Chevy intake having the Dominator carb flange.
These days ... I don't know whether you get that manifold from Bill Mitchel Products or World Products; maybe both.

[Kevin Willis]

First I would like to thank everyone for the input. The discussion has leaned toward the heads. I was leaning toward these heads because they were one of the bigger conventional heads. So with that being said. Is there a readily available 23* head that would be better. The heads have not been purchased yet.

[user-17438]

First I would like to thank everyone for the input. The discussion has leaned toward the heads. I was leaning toward these heads because they were one of the bigger conventional heads. So with that being said. Is there a readily available 23* head that would be better. The heads have not been purchased yet.

Is there a reason you are stuck to 23 degrees? It's easier to get the rights size in 18 or 15 degree variants.

Edelbrock had a 23 degree casting that would go 300cc. Not sure if it's available any more.

There are many routes you can take. What us your goal hp wise?

[Scotthatch]

First I would like to thank everyone for the input. The discussion has leaned toward the heads. I was leaning toward these heads because they were one of the bigger conventional heads. So with that being said. Is there a readily available 23* head that would be better. The heads have not been purchased yet.

Is there a reason you are stuck to 23 degrees? It's easier to get the rights size in 18 or 15 degree variants.

Edelbrock had a 23 degree casting that would go 300cc. Not sure if it's available any more.

There are many routes you can take. What us your goal hp wise?

I agree .....23 degree head will only get you so far

[maxracesoftware]

First I would like to thank everyone for the input. The discussion has leaned toward the heads. I was leaning toward these heads because they were one of the bigger conventional heads. So with that being said. Is there a readily available 23* head that would be better. The heads have not been purchased yet.

The heads have not been purchased yet.

the way i read your 1st Post , i thought you already had an old pair of the 1st design AFR 245cc Heads ??
"the 1st design AFR 245cc Heads" , because of no mention of the AFR245 NPP new version

even the older 1st 245cc AFR were a great improvement over their previous Heads
and the AFR245NPP is a giant leap in correct direction !

an Edelbrock #2970 maxed-out Plenum area like MTENGINE's on AFR245NPP Heads
and a Holley HP1250 CFM Carb would make a lot of HP

if you want to stay with 23deg type Heads then :
to go a major step forward in 23deg Head , would be the All Pro 23deg Heads
like these from BES :
http://www.besracing.com/cylinder-head- ... -pro-rr245

a pair i Ported with Dyno results .. but a miscommunication , the Sheet Metal Runner transition ended up choking off some flow
still had decent HP ... i'm pretty sure we could have made close to same HP with a good Single plane Manifold .
http://www.maxracesoftwares.com/forum/v ... ?f=5&t=225

i almost forgot about this 440cid Combo for John Wilson
John Wilson's SBC 440cid 871 HP Brodix 18 degree Heads
Peak TQ = 657.0 @ 6100 RPM
Peak HP = 871.0 @ 7700 RPM

Cam Specs are in the PipeMax picture

http://www.maxracesoftwares.com/forum/v ... ?f=5&t=105

[Walter R. Malik]

Be aware that the All-Pro, BES head mentioned is a "Raised Runner" 23 degree head, not standard intake port location.

Also, Brodix offers a CNC ported "Track 1" standard 23 degree intake port location with 245 cc intake ports having 2.150" intake & 1.600" exhaust.
The Kuntz designed, CNC ported "Motown 23" head has 250cc intake ports and can use stud type hardware.
The latest AFR heads do use lighter 8mm stem valves, though.

[swampbuggy]

MT Engines----I am a very close friend of Kevin, so i can tell you there are already brand new high quality Diamond pistons and are for a 23 degree build. Mark H. Kevin may share more ??? BTW i am on this forum MORE than him Just try'in to help him out a bit.

[Walter R. Malik]

MT Engines----I am a very close friend of Kevin, so i can tell you there are already brand new high quality Diamond pistons and are for a 23 degree build. Mark H. Kevin may share more ??? BTW i am on this forum MORE than him Just try'in to help him out a bit.

If what you say is true then those pistons probably are not made with valve reliefs for 60/40 valve spacing which the AFR and Brodix heads have.

[swampbuggy]

Walter, you just may be on to something there. I will have to ask Kevin about what you have said, THANKS, Mark H.

[Kevin Willis]

Again I would like to thank everyone for there input, I never thought this post would get this much response. This is what I have to work with so far.
Dart little M, Callies Magnum 4", Manley pro series 6", Diamond 4.185 bore 2.6cc EDV, for 23* valve , I thank .060/.040 based on some measurement
I made, going to call Diamond tomorrow. We also have a set of Dart Pro1 230, with hand porting ( I don't thank is any good/amateur) the Dart intake,
that is milled considerably to match heads. Tring to convince customer he needs a new valve train and top end. Tring to make strawberries out of horse crap!

[swampbuggy]

Question For Larry M. please. Larry i have for my SBC build a set of Brodix 18 Deg. C heads. Kevin and I have been doing some flow testing on them. They have been CNC'd to the brodix program BP 18 SP C program. Could (or) would you possibly tell us the details on those 18 deg. heads that were in the 871HP 440 CI test you shared. We are building a 4.185 x 3.375 winger and i am considering going to Darts 9 deg. head for several reasons, but i am torn on what to do, already have intake with a lot of work in it. Wanting to get to 2 hp/ci .

[maxracesoftware]

Question For Larry M. please. Larry i have for my SBC build a set of Brodix 18 Deg. C heads. Kevin and I have been doing some flow testing on them. They have been CNC'd to the brodix program BP 18 SP C program. Could (or) would you possibly tell us the details on those 18 deg. heads that were in the 871HP 440 CI test you shared. We are building a 4.185 x 3.375 winger and i am considering going to Darts 9 deg. head for several reasons, but i am torn on what to do, already have intake with a lot of work in it. Wanting to get to 2 hp/ci .

the 871HP 440cid had older pair of Brodix 18deg Heads
Brodix has probably made improvements since then to these castings , plus they offer better 18deg versions now
... one more thing--> that engine could have used more Camshaft + a larger Carb CFM along with the Cam, would have made more HP
the Oil Pan was not a full length kickout Pan , that would have made more HP ... so on a killer 371cid it could make enough HP for you ??
its hard to say ??

the Dart 9 degree Heads/Manifold on a little 371cid would be the best way to go

i just recently Dyno tested a 333cid 901.2 HP @ 9700 RPM with Dart 10deg Heads slightly Angle-milled to 9.8 deg
but those too were old 10deg Heads .... switching over to current 9deg Dart combo would make a bunch more HP
... with 9deg on a 371cid it would not have any Dome + better Combustion + much higher Flow CFM