Don Terrill’s Speed-Talk

Will this combo make 650HP on pump gas?

Iron eagle block. 4.125strokeX4.155bore
11.5CR
Roller cam: 305/311Adv., 293/279@.050", .680/650"(+1.6RR), 110LSA
AFR 245NPP Heads.
Ported Super Vic II and Dominator
1/3/4-1/7/8 step headers.

Comments?

Sorry @.050 Intake was incorrect. 273@.050".

If that wouldn't at least make 650 on pump gas, I would be pretty disappointed.

cgarb wrote: ↑Mon Mar 12, 2018 3:52 pm If that wouldn't at least make 650 on pump gas, I would be pretty disappointed.

I'm with him!! I would say somewhere like 725+ is more like it!

Calculated Dyn. Comp. Came in at 8.15. So with good a cooling system 93 octane pump gas should be OK??

Go to www.performancetrends.com and down load their Engine Analyse Pro simulation software (it’s free for ten days) and
enter your engine data and you will get a very close estimate. I’ve done engines similar to yours and the simulation and the results on my dyno were very close. This has been discussed here before but, I guess you missed that class.
Greg Finnican
Charlotte, NC

If it's going to be more of a street car running 92 octane gas, I'd go with no more than 10:1 compression with a cam with 250 duration @ .050". I'd think you could still make your 650 hp goal with that setup.

I was going to say that is too long duration.

I would hope it makes around 700hp with that much duration.
You could work the chambers some to lower the comp a bit if needed.
Also the step headers may loose a bit, 1 7/8" should make more.
Some will recommend 2" headers.

Talked to the head guys. They recommend a smaller duration cam. 267/273 @ .050".

Thanks for the inputs.

i know what big Joe would say if he was here , go with the one u have, its a 440 , not a 350

"And rev it up!"

sstpres wrote: ↑Wed Mar 14, 2018 3:13 pm Talked to the head guys. They recommend a smaller duration cam. 267/273 @ .050".

Thanks for the inputs.

You still haven't clarified the application: Track-only? Street/strip? "Big" stall or stick-car? Etc., etc., etc., ...

How high are you willing to spin it? Do you have a max RPM limit based on components used or life expectancy?

FWIW, my 11.5 CR 452 ci BBM has a 266/266 @ .050" x .650+" solid roller... street/strip pig, although the engine still needs to get stuffed back in the car after last fall's dyno flog.

It's a street/strip deal. Motor only. Pump gas. Don't want to spin it over 7500. Going in front of a Coan TH350. We'll have them spec a converter.

Using a Bullet roller.

301/266 .450" Lobe
313/268 .452" Lobe
LSA- 108
1.65/1.55 shaft rockers.