Porting My Edelbrock Cylinder Heads

[360tripleblack7]

Hello Guys,

Three months ago I decided change my J-Heads for a Edelbrock Performer RPM.

After read a lot of articles, books and talking with some engine builders I decided porting the cylinder heads myself.

I already make it in my J-Heads but just a Stage II and another guy finished the job...

After two months of a hard work finaly I finished the heads and went to a speed shop to measure the gain that hope have in a flow bench.

Well, below the numbers that I got and some pictures...

Please, if someone have a tip to me improve my job, I appreciate...

Volume:
Intake: 193cc
Exhaust: 84cc
Combustion Chamber: 65.2cc

Flow Data:
Lift Intake Exhaust
.100" 75,8 62,0
.200" 162,2 109,2
.300" 228,9 160,8
.400" 263,3 189,2
.500" 277,6 208,8
.600" 283,7 222,3
.700" 289,6 224,8

 

[Carman340]

Those flow numbers look very impressive for those heads. Both
intake and exhaust.
I have heard of people getting over 300cfm from the intake side but they broke through
and had to plug it. The car those heads went in runs mid 11.'s

 

[rumblefish360]

Did you test the head before you did any porting?
The reason I ask is the flow bench your using maybe slightly different than another bench.
It would have been better to measure the gain from stock to ported on the same bench.

A restriction from what I have read, is the pushrod pinch area. The less that's ghere the better.

 

[360tripleblack7]

Yes Rob!

If you look in the pictures, you can see that I keep runner and chamber #3 stock for me have a reference.

The numbers that I found is very similar that Edelbrock show us...

About the restriction area, I think that the pinch is the bigger... My future plans is buy the offset rocker arms from Hughes and remove the pinch area like the Big Mouth... But it's just plans... LOL...

 

[rumblefish360]

Then you already know that you'll need to drill and plug the heads pushrod holes. I do beileve Hughes sells a kit to do this.

 

[rumblefish360]

Like so;

 

[Aspen79]

I have the same heads I have had just a little bit of work done. They are out getting a competition valve job now. Please let me know what kind of power you make. What motor combo are you running?

 

[360tripleblack7]

I was running with this combo:

'77 318 block + 360 Crank
Scat I-Beam Rods
KB Hyper flat tops 10.3:1
Mopar Purple Cam .557/.557 mec. cam
Mopar J Heads Ported 2.02 / 1.60
Proform Roller Rockers 1.5
Professional Products Air gap intake OOTB
Mighty Demon 750
TTI 1 5/8 Step 1 3/4 Headers
904 Auto trans with TCI Rebuild Kit

Street car with 3350lbs All Motor...

Best time is 1.79 60ft - 7.74@88 1/8 - [email protected] 1/4

I believe that this combo have between 420 - 440HP. I never tested on dyno... Just based on time slip

With new heads I hope that I can got + 50HP... Maybe...

 

[stroked340]

I have a set of those on my 360 with a "street" port job from Best machine been 11.79 with a stock stroke 360...

 

[Norway-dart]

Remember flow alone is only part of the hp, to gain hp, you need more cfm @ correct port size, because you need to take advance of the velocity/speed of air to get the engine packed with more air and hp

 

[360tripleblack7]

Finished Exhaust Runners!

 

[Aspen79]

I was running with this combo:

'77 318 block + 360 Crank
Scat I-Beam Rods
KB Hyper flat tops 10.3:1
Mopar Purple Cam .557/.557 mec. cam
Mopar J Heads Ported 2.02 / 1.60
Proform Roller Rockers 1.5
Professional Products Air gap intake OOTB
Mighty Demon 750
TTI 1 5/8 Step 1 3/4 Headers
904 Auto trans with TCI Rebuild Kit

Street car with 3350lbs All Motor...

Best time is 1.79 60ft - 7.74@88 1/8 - [email protected] 1/4

I believe that this combo have between 420 - 440HP. I never tested on dyno... Just based on time slip

With new heads I hope that I can got + 50HP... Maybe...

I have a similar setup I am puttin together.
360 stock stroke
.030 over
11.5:1 CR
Eddy air gap intake (port matched)
3600 stall 727 trans
Car is about 3500 lbs
I'm hoping with a 200 shot (fogger)of juice I can get high 10's

 

[Aspen79]

I have a set of those on my 360 with a "street" port job from Best machine been 11.79 with a stock stroke 360...

Thats pretty good.. I hope I can get that on motor and 10's on 200 hp shot