Just got done with a set of RPM heads

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MRL Performance

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Here is the flow data for the EDDY RPM BBM 84cc heads. Mild bowl work, laid the short turn back, opened up the intake port a bit taller and put a 2.19" intake valve in it. Not a full port job by any means, but the flow is nice. This head in the right High Compression combo will make well over 700HP.

Intake
.100 78
.200 159
.300 237
.400 288
.500 310
.550 317
.600 320
.700 327
 
I have a set of these heads on my engine already. we have previously discussed building me a stroker short block. Could you PM me the cost that was involved with working the heads? I would like to work my heads when i build the new short block.
 
AH HA! See Mike, I told you you didn't need me. You have verified what I have been saying, these and the Stealths will really flow big. You just gotta believe.
 
IQ52 said:
AH HA! See Mike, I told you you didn't need me. You have verified what I have been saying, these and the Stealths will really flow big. You just gotta believe.
Click to expand...

The biggest pain was getting the seats. Special order and took 2 weeks. I was quite happy with the results for the amount of work I had into the porting.
 
No. They were bare heads to begin with. I have base line flow numbers for OOTB RPM already. They dont flow any where near this OOTB!
 
Those are really good mid lift flows. Very nice design Mike!
 
MRL Performance said:
Here is the flow data for the EDDY RPM BBM 84cc heads. Mild bowl work, laid the short turn back, opened up the intake port a bit taller and put a 2.19" intake valve in it. Not a full port job by any means, but the flow is nice. This head in the right High Compression combo will make well over 700HP.

Intake
.100 78
.200 159
.300 237
.400 288
.500 310
.550 317
.600 320
.700 327
Click to expand...

I would think they should make that with pump gas comp. on the right engine! Kind of a shame Edelbrock doesn't put larger valves in them to begin with.
Are you using them for a build?
 
I'm with Brian. I wonder how many of you REALLY realize what a great set of heads this is?

THEY'RE SMOKING! Even if you think small.

Put these on a 10:1 440 with a good intake, a roller cam, .520" lift, headers, pump gas and it will go 600+ horsepower by 6000 rpm.
 
MRL Performance said:
Here is the flow data for the EDDY RPM BBM 84cc heads. Mild bowl work, laid the short turn back, opened up the intake port a bit taller and put a 2.19" intake valve in it. Not a full port job by any means, but the flow is nice. This head in the right High Compression combo will make well over 700HP.

Intake
.100 78
.200 159
.300 237
.400 288
.500 310
.550 317
.600 320
.700 327
Click to expand...

How about these heads with 512 ci.
Heads cut to 75 cc
-17 dish pistons
Comp ratio should be 10.93-1
And a .580 hyd cam.
Hp guess and how far out are you on head work.
I have the short block and a set of stock RPM heads.
Thx
 
Ok so I was pretty happy with those numbers. I looked at the heads and had a vision of how to make it a little better. So after some more work in the ports and chambers, here are the final numbers.

Intake/Exhaust/% Balance

.100 77/62/80.5%
.200 156/122/78%
.300 234/163/69.6%
.400 286/207/72.3%
.500 315/241/76.5%
.550 324/251/77.4%
.600 329/260/79%
.650 340/267/78.5%
.700 342/273/79.8%

I lost a touch of flow in the .200-.400, but gained good flow after that. This is the most flow I have ever got out of a set of RPM heads, but then again its the first time I ever put the 2.19 intake valve in them.
 
Yeah baby, put those on a 512! Now the non-believers can call both of us crazy.
 
HAHA I was quite surprised at the flow and the velocity. I gota say Im pretty proud of these heads. A alot of work, but the dyno will tell the story if it was worth the time.
 
It'll be worth it Mike. As you know our RPM heads that flowed like that made 723 HP on Comp Cams dyno. I know how much you like Comp's dyno. Anybody who already owns a set of RPM or Stealth heads doesn't need to buy Indy heads to make over 700 HP.
 
One of you guys should let me send a set of brand new 440-1 CNC 325's to get the chambers smoothed out and valves unshrouded for a 4.500 bore, and a decent valve job and see how they flow. As they come from Indy they are junk IMO because of the CNC finish in the chamber (especially around the spark plug) and maybe not ready for 0.700 lift.
 
airwoofer said:
One of you guys should let me send a set of 440-1 CNC 325's to get the chambers smoothed out and valves unshrouded for a 4.500 bore, longer valves and springs installed and a decent valve job and see how they flow. As they come from Indy they are junk IMO and not ready for 0.700 lift.
Click to expand...

The only set that I've tested wasn't to bad. I wasn't happy with the way they were set up and we made some improvements in spring locators, retainers and locks. They came to me used and we did a valve job. If you are changing to a longer valve, go to a larger head also. These came with a 2.19 intake and the 2.25 should help.

Lift...............as received...............w/valve job

.100.................66/60......................76/64
.200...............141/114...................156/124
.300...............212/163...................221/173
.400...............267/207...................272/214
.500...............309/241...................308/249
.600...............347/267...................346/275
.700...............360/285...................361/295
.800...............369/294...................375/312

Really, that's not to bad. Just by looking at them there were some improvements that could be made with some more porting, but we weren't authorized and the engine didn't need it for the purpose intended.
 
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