Anyone want to run some numbers for me again????????? Please!!!!

Previous data:

- 460 c.i.
- 11 : 1 compression
- 4.250 bore / 4.00 stroke
- 800 cfm carb
- rpm air-gap
- 2" X 31" X 4" headers
- .510 lift 234 dur @ .050 hyd.
- 5500 RPM max to be safe...

Here's numbers we didn't have before......
2.19 intake 1.88 exhaust
If I read the chart right...my heads flow around 320 cfm.

As a guess a good port job should put me somewhere between stock numbers and AFR 305's???
- lets say 335 cfm...?

Here is another hyd. Isky cam I'd like to try as a comparison...

- .590 lift / 292 ADV dur. / 244 @ .050 / 108 deg. lobe center

Also, lets take it to 6500 RPM...

OK here's what I'd like to try:

- 460.7 c.i.
- 11:1 compression
- 4.250 X 4.00 b/s
- 800 cfm carb
- Edel. RPM AIR-GAP intake
- 2 X 31 X 4 headers
- .590 lift / 292 ADV dur. / 244 @ .050 / 108 deg. lobe center
- 6500 RPM maximum.


Thanks guys,

A.....

Ok..I re ran the numbers using a Voodoo cam with similar duration numbers. I also stepped up the head flow to what I thought the head may possibly be. The highest flowing factory heads were in the 300-310 range from the info I can find so these #s may be a bit inflated. I think most rectangle ports could be easily ported to the 320-330 range. The closest head I had on file to that was a Canfield alum head. I also think you could gain more with a solid lifter or a roller setup.

Again..as with any compter dyno program take these with a grain of salt..

with the small cam/dual plane
470hp@5500 527ftlbs@3000

with small cam/single plane
490hp@5500 529ftlbs@4000

with small cam/single plane/ported heads(used 305 Canfields for flow)
534hp@5500 544ftlbs@4500

with large cam/dual plane
504hp@6000 511ftlbs@4500

with large cam/single plane
535hp@6000 525ftlbs@4500/5000

with large cam/single plane/ported heads
574hp@6500 542ftlbs@5000

You da Man!!!!!!! Would a bigger carb help? or not really due to elevation. I'm at 7000'

I dont think you need to. I think getting the carb set up right is far more important than a minimal gain in CFM. Not to mention the added cost.
Most you are going to gain is about 50 CFM unless you go to a dominator type carb. 950 HP carbs only flow about 830 cfm and the 1000 HP carbs are 870 cfm. They are tested differently vs the older series of carbs. Same with the Barry Grant line of carbs is what Ive been told.
I believe the Prosystems 950 flows 900 cfm that is on our 468 but has a different baseplate than the HP.

I didn't know the BIG carbs were measured differently. The Q-jet book I have by Cliff Ruggles states that my 800 can move up to a 850 if I remove the inner venturi....I have a date with a q-jet guru in northern CO named Lars Grimsrud, He is a Corvette guy. I've run my engine with a Holley 750, and it ran good. But, the feeling of power I had with the Q-Jet when the secondaries opened up all the way with the right rods was UNBELIEVEABLE!!!!!! I'm just working on getting the whole idle to wide open spectrum to work fluidly...

I talked to Cliff about a full boogie Qjet for the pull truck at one time. He said not a problem and that he had the ability to get almost 900cfm out of it depending on what he did. Im willing to bet that a purpose built Qjet from him will be within 10 hp or less than a purpose built 4150 Holley from most anyone else. In his testing for Kaufman Racing he has done back to back testing on their engines and dyno against his own prepped Holleys and the Qjets are within 5hp +or-. Cliff's one downfall is turnaround time.