Head chamber cc choice, whats the best?

[69 GTX]

So I'm getting ready to pick a alum head to start my RB 440 engine build. I'm wanting to go with a 0 deck piston. Also would like to run 90-91 octane pump gas. I know that a lot depends on the cam but lets say that I will be using a 230-240 @ .050 duration cam with a 112-114 LSA. Whatt cc chamber do you think would be best with a .040-.045 head gasket.? Looking to get the best quench possible to help run as much compression as possible within the above specs? Any thoughts therorys welcome.

 

[super-bee_ski]

Hmmm
Give Hemi Rebel, Mike Gaines, Meep-Meep, IQ52 and a few others a shout....

I do know the "bigger CC Engines such as the 440 CI can handle a higher compression head

The 3 common sizes are: 75cc / 84cc / 88cc

 

[lewtot184]

the edelbrock/stealth closed chamber would work. i think i'd wait until the trick-flow heads came out to make a decision.

 

[69 GTX]

Yes I wish they would hurry up!

 

[TetanusShot]

According to my handy dandy calculator: a stock stroke, +.030 440, at zero deck with no dome or dish, .039 fel pro head gasket, and an 84cc chamber makes 10.7:1. 88cc makes 10.3:1 and 75cc makes 11.72:1. about 446 cubic inches

 

[69 GTX]

Sounds like I may have to opt for a D shaped dish piston........ I'm trying to get as good a chamber/quench as possible so I can push the timing and compression a little more.

- - - Updated - - -

Tet can I ask you to share that formula with us?

 

[super-bee_ski]

69 GTX,

Check out IQ 52s latest post on Edelbrock heads!

http://www.forbbodiesonly.com/moparforum/showthread.php?96274-Edelbrock-RPM-heads

IQ 52 has done a great job with terrific numbers on a set of Edelbrock RPMs
Worth "looking into"


His post (Without the pics)
see copied URL for the entire post:

IQ52 posted:
So, while everyone is waiting for those inexpensive TrickFlow heads.

Here are some 84cc RPM 440 heads we are finishing up. They still need to be cc'd, finish milled and assembled.

Lift.................OOTB IN/EX 2" EX tube.................Ported

.100..........................73/59................................73/61
.200........................148/125.............................158/130
.300........................209/166.............................220/181
.400........................254/196.............................277/220
.500........................276/219.............................314/246
.600........................282/234.............................333/267
.700........................287/242.............................343/283
.750.............................................. ...................349/NA

 

[TetanusShot]

Tet can I ask you to share that formula with us?

Its an excel sheet i programmed that i can plug the critical dimensions into and it puts out the relevant information (cr, displacement, deck clearance...).
CR=(volume at bdc to deck surface+gasket volume+chamber volume-dome volume)/(all that same stuff-swept volume)
For converting cc's to ci I used 0.0610237441 ci per cc
Hope i typed all that correctly...

 

[IQ52]

So I'm getting ready to pick a alum head to start my RB 440 engine build. I'm wanting to go with a 0 deck piston. Also would like to run 90-91 octane pump gas. I know that a lot depends on the cam but lets say that I will be using a 230-240 @ .050 duration cam with a 112-114 LSA. Whatt cc chamber do you think would be best with a .040-.045 head gasket.? Looking to get the best quench possible to help run as much compression as possible within the above specs? Any thoughts therorys welcome.

With an 84cc head, zero deck and a piston with 4.5cc valve notches, .039 8519PT1 head gasket I've got you at 10.26:1. With the cam you listed I think you are close but a bit edgy at 91 octane and I think a slightly bigger cam is in order. 230 @ .050 nope, but the 240 @ .050 could swing it.

 

[69 GTX]

Thanks IQ

 

[383man]

I went with the basic Indy EZ head on my 440/493 which is sorta a heart shape chamber. They are 75cc stock. I used a D-dished piston and the flat is .006 down as with the .039 gasket I use it has .045 quench and it came out to 10.6 comp when all added up. I run on 92 pump all the time with no ping and 37 total timing. But I run more cam as I use a solid flat tappet cam thats 264 & 270 at .050. It has .585 and .592 lift and a 110 LSA. I have it in the eng on a 106 ICL. I use the Indy dual plane intake with an 850 Holley DP. I drive and race on 92 pump and I have been for the 4 years its been in my car with no problems. In fact I have never had race gas in the car nor have I ever uncapped it. But this setup with good quench and the Indy EZ head works real nice for me. Ron

 

[69 GTX]

Thanks Ron. I'm sure the cam is taking a bit more compression out for you. I may have to go to the 88 cc chamber or a dish piston. I'd really like to stay closer to 230 @ 50 duration. I'd like there to be very little lope in the idle.

 

[texas69bee]

Play with this to get the #'s you want.
http://www.summitracing.com/expertadviceandnews/calcsandtools/Compression-Calculator/

 

[Garys1969RR]

Sounds like I may have to opt for a D shaped dish piston........ I'm trying to get as good a chamber/quench as possible so I can push the timing and compression a little more.

- - - Updated - - -

Tet can I ask you to share that formula with us?

You can also log into the United Engine and Machine website, they have a C Ratio calculator on there. They manufacture the KB piston.