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View Full Version : Head recomendation for a 540


Tod74
09-15-2007, 03:44 AM
Ok,I have a 540 inch motor based on a Merlin III block. I currently have stock 074 aluminum heads on it with a victor jR. 454 R and 1050 Dominator. cam is a crane roller .737int .726 exh. 274 284 @ .050 114 lobe seperation angle. with the 4,7 swap. I am going from memory here..it could be 112 lsa don't have the card handy..I want to get some new heads this winter,but want to make sure I get something that will work with my rpm range and cubic inch.The motor has a rotating assembly from Ohio Crankshaft,and after reading this forum,I do not know how well it will stand up to abuse.I wanted to keep the rpm at or below 7000.The pistons only have a 36 cc dome which is supposed to be around 13.1 with 119 cc heads.I was thinking of maybe some 2x brodix or some AFR..actually leaning toward the AFR 325 as cast or the 335 cnc..wanted to get some input from you guys...The issue I have with AFR cnc heads is they open up the chambers to 121 cc,which won't help my already sorta low compresion.
My question is; Is this port size good for my application? Also,they offer the heads in 114 cc,which I assume means they will mill them.If I go that route,how will that effect the flow? Also,sorta hesitant to buy a set milled because I don't want to invest in new heads and have them cut,then later if I do something different with the motor be stuck with expensive heads that have already been cut. Any help would be greatly appreciated. Car is a 3000 lb Nova with a Powerglide,8 inch converter and transbrake. 32x 14 slicks,5.13 gear. 1/8 mile car only. The way it is now ran 6.35 108 mph with a 1.32 60 ft.shifted at 6800...felt like it nosed over on top so I shifted it at 6400 and got a 6.28 out of it but I think that was a bit too early. I haven't actually checked as to where the converter stalled to,but the same converter stalled to 5200 behind a 454 I had a couple years ago with the same heads and almost same cam. This is a new set up and I have only ran it twice...stuck the old heads on just cause I had them and wanted to try it out before winter. SORY for writing a book here guys.Just wanted to be thourough. :oops:

lmchevy
09-15-2007, 06:49 AM
As far as your rotating assembly goes it will be fine.Ohio cranks are forged in China, the same place as an Eagle crank.As far as the heads if you want an as cast head Dart pro1 345.

Tod74
09-15-2007, 09:22 AM
As far as your rotating assembly goes it will be fine.Ohio cranks are forged in China, the same place as an Eagle crank.As far as the heads if you want an as cast head Dart pro1 345.

I didn't know that...I thought they made their cranks themselves...shows what I know. Thanks for the response.

bjuice
09-15-2007, 11:00 AM
there are many great HEAD guys on here that will be along soon...
Par racing engine are turning out over 1,000 hp on their 565ci with the new Brodix Oval port head...Scott duggins has really good things to say about this head.....Ed or Curtis Boggs can guide you the right way here for sure.

Brian

superstreeter
09-19-2007, 05:19 PM
Hey tod74,,I`m sort of doing the same thing with a 588,,I`m really looking at the AFR 357 CNC, and want to keep mine under the 7000 range also, I have been using a set of shaved 305s from afr and they work good, but like yourself, I would like to try something bigger,you are running more comp. and cam than me, so either the 357 or the 335 should work,,the 335 would give you a little more torque. they both flow about the same to 700 lift.

rpmengine
09-20-2007, 01:46 PM
The AFR heads are a CNC'd chamber. The 114 cc is not a milled 121cc. We use AFR quite often. Mike@ RPM

Tod74
09-20-2007, 04:33 PM
The AFR heads are a CNC'd chamber. The 114 cc is not a milled 121cc. We use AFR quite often. Mike@ RPM

Do you have any suggestions on which head fits my application the best?

superstreeter
09-20-2007, 07:11 PM
so mike if I understand you correctly,,,I can get the 357 afr cnc head, in a 114 cc version,as well as the 121 cc version? and that the 114 is not shaved ?

Tod74
09-21-2007, 04:36 AM
so mike if I understand you correctly,,,I can get the 357 afr cnc head, in a 114 cc version,as well as the 121 cc version? and that the 114 is not shaved ?

I understand what he was saying..since it is a cnc chamber they would just cut it at 114 cc rather than mill a set down...which makes more sense than to think they would mill them,But in their catalog they do not list an "as cast" 114 just 119 .Then it says "Flat milling available -114 cc maximum; note milling head deck will effect flow numbers."

I am sure he knows what he is talking about since he has used their heads before..the above quote from the catalog was what gave me the idea they were milled.

kwillymac
09-21-2007, 10:45 AM
I think you should call some head experts and get their opinion with the cam you are using. I have a friend with a 10:1 555 Musi motor. It came with the 360/370 cc Edelbrock/Musi ported 24 degree heads. He took them off and bought 335 AFR Heads because someone guaranteed him a better ET. He went to the track and lost a tenth on his short time and ran a tenth slower with the same MPH. It depends on cam and compression.

cboggs
09-21-2007, 05:23 PM
I build a CnC Edlebrock victor that is perfict for your combo, ..
will run better then the other heads but mostly because we are a custom
shop and I personally do every valve job on every head that we do.

Curtis

edvancedengines
09-22-2007, 09:26 AM
cboggs
MASTER BUILDER


Joined: 01 Oct 2004
Posts: 192
Location: Woodbridge, VA
Posted: Sat Sep 22, 2007 1:23 am Post subject:

--------------------------------------------------------------------------------

I build a CnC Edlebrock victor that is perfict for your combo, ..
will run better then the other heads but mostly because we are a custom
shop and I personally do every valve job on every head that we do.

Curtis
_________________
----------------------------------------
Race Flow Development
Simultaneous 5-axis CNC Porting
http://www.raceflowdevelopment.com


My suggestion also.

After carefully examining the advantages, disadvantages, and getting deep into the technicnical aspects of them, I too will highly recommend that Race Flow Development (RFD) 24 degeree Edlebrock from only Curtis Boggs above all the rest in that competitive price range.

I should be close to ready for dyno testing these in appx 2 months, if things go according to plans.

So we are putting our (My Customer's) money where our mouth is, and also our reputatuion where our mouth is by using these heads. That is how sold on them I am.

Ed

Tod74
09-22-2007, 10:33 AM
Thanks for taking the time to responde guys.

superstreeter
09-23-2007, 03:25 PM
well finally got a hold of a dealer for afr ,and in order to get 114 cc heads they cnc them to 121cc, then they shave them down about .042 ,flat mill they call it.to achieve the 114 cc. So there is only 1 casting that they use for all bbc heads.Too bad, I was looking forward to a smaller chamber.

cboggs
09-24-2007, 08:44 PM
well finally got a hold of a dealer for afr ,and in order to get 114 cc heads they cnc them to 121cc, then they shave them down about .042 ,flat mill they call it.to achieve the 114 cc. So there is only 1 casting that they use for all bbc heads.Too bad, I was looking forward to a smaller chamber.

That's the way they all are done, .. Dart CnC, RFD CnC, Brodix etc, ..
No one has a special chamber for 114cc we just mill the deck.

that being said, .. it's really no big deal to mill the deck of a good
aftermarket head .040" or so, .. heck we angle mill the Victor
and Dart castings over .100" at times.


Curtis