Edelbrock RPM heads

[IQ52]

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

 

[lewtot184]

have you experienced any exhaust port failures due to cnc'd porting? do you use your own program?

 

[68 HEMI GTS]

have you experienced any exhaust port failures due to cnc'd porting? do you use your own program?

those are hand ported

 

[Roughbird72]

Wow!

 

[lewtot184]

those are hand ported

???

 

[IQ52]

Yep, hand ported. I've not heard of a CNC program that can pull those numbers. All our stuff is hand ported. We've put the standard Stealth head to 354 cfm @ .700" lift.

The tough thing is the RPM heads are getting some casting shift now and making things dicey.

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have you experienced any exhaust port failures due to cnc'd porting? do you use your own program?

No failures on our stuff. If we know for certain the header openings and gaskets being used we can push the exhaust flows on the heads over 300cfm with the 1.81" valves. These heads have 1.78" exhaust valves and we could might do the same thing, just haven't tried.

 

[lewtot184]

one of the major head porter's cnc'd program left the right side exhaust port (as your facing the exhaust ports) thin and they would break thru after some use. this made me leary of cnc'd heads. i did hear some "hearsay" that there would a casting change but don't know any details or if it even happened. this info is from a friend who lost his engine due to break thru.

 

[IQ52]

They need a casting change as the standard Stealth head is a more uniform casting than the RPM right now.

 

[lewtot184]

those are hand ported

your right. i've got cnc paranoia in my brain.


those are very good numbers.

 

[WileERobby]

I thanked you. No, not for your nice work on the heads. Because you were thanked 666 times.

 

[Cranky]

Nice numbers! I had a pair checked some years back and they flowed just a bit better out of the box than a pair of max ported 906's I had at the time. Thing is, the RPM heads have a better combustion chamber, port config and plug placement than the factory heads do.....

 

[Hemirunner]

Looks great!! Nice numbers as usual!!

 

[gearheadbill]

What does a tricked set of these RPM cost?

 

[69 GTX]

IQ what head do you feel has the best combustion chamber (RB 440)

 

[IQ52]

What does a tricked set of these RPM cost?

Supply me a set of complete RPM or Stealth heads and a ported set will be returned to you inspected, spring pressures checked, assembled, ready to bolt on, with new intake valves, intake seats, seals and valve spring shims, original exhaust valves, springs, retainers, locks and spring cups. The valve heights and installed heights would be equalized. They will be cc'd and combustion chamber surface milled. This would cost 1,735.00 plus shipping and replacement of any defective parts. I also recommend replacing the retainers and locks on the Stealth heads (if they are the originals) for an additional $80.00.

 

[IQ52]

IQ what head do you feel has the best combustion chamber (RB 440)

I have no valid test data I have personally collected to make a decision on the best shape.

 

[dieseldazzle]

I have no valid test data I have personally collected to make a decision on the best shape.

Sounds like a challenge lol

 

[Canyon707]

Has anyone heard of Killians Porting services? I spoke with Jerry Killians last week and he is posting up a set of RPM heads this week check out his site.

 

[383man]

Yep, hand ported. I've not heard of a CNC program that can pull those numbers. All our stuff is hand ported. We've put the standard Stealth head to 354 cfm @ .700" lift.

The tough thing is the RPM heads are getting some casting shift now and making things dicey.

- - - Updated - - -



No failures on our stuff. If we know for certain the header openings and gaskets being used we can push the exhaust flows on the heads over 300cfm with the 1.81" valves. These heads have 1.78" exhaust valves and we could might do the same thing, just haven't tried.

Are you saying them RPM heads had 1.78 exh valves ? I thought the all RPM heads came with 2.14 and 1.81 valves in the RPM heads. ? Ron

 

[Garys1969RR]

Very impressive flow numbers there. Can you say what the expected peak horse power would be on a well built 451 with these heads? Using a solid lifter cam around .600 lift, 295 to 300 total duration, C/Ratio of 11 to 1, .040" quench, Victor intake, 850 to 950 CFM carb. Any way to predict peak horsepower with a combination like this? Or do you have a similar build that you have dynoed? Ok thanks.