Don Terrill’s Speed-Talk

I think I HAVE A SET OF ROLLER fulcrums for use with canted valve stamped rockers only a few months use 150.00 might still have the rockers too. Crane made them.

This build went from mild to wild in about 2 days.
Current situation:

Scat rotating kit for 502 cubes with flat top pistons. (11-1 CR with these heads)
AFR #3805 aluminum heads and the matching intake.

I had planned on the biggest comp thumper cam. (242 / 257 @ .050 107 LSA / .531 / .515 lift) now it seems small.

Brian

Now comp 34-652-5 seems more likely.

Anyone have any experience with these AFR 280cc 460 heads? With the different valve angles and notching the pistons?

this is the cam i bought:

http://www.cranecams.com/product/cart.p ... il&p=24519

246 / 256 @ .050
.563 / .583
108 LSA solid flat tappet.

Afr heads with 280 cc intake ports, 85 cc chamber, 11-1 CR
matching AFR single plane intake and a Holley 950 Street HP.
502 cubic inch with Scat internal balance rotating kit.
Any power estimates?
I would have went bigger on the cam or to a roller but the valve angles on the head and the thought of notching the pistons made me want to stay away from alot of lift.

That will probably be a brutal torquer but I'm concerned about your 11:1 compression and smallish cam. Think you'll be ok?

I second what rev theory said with that small cam & relatively small head for a 502. And on the valve notch thing it isn't adding lift that gets you into p-to-v clearance problems, it's adding duration. p-to-v clearance issues occur during valve overlap when the piston is near TDC, not when the valves are at max lift.

Well its a heck of a better head than the old iron heads i was originally planning. Also i've found P-V clearance is often tightest on the exhaust valve when the piston is chasing it up on the exhaust stroke. Seeing as this is a flat top piston i'm hoping to not have to notch them. However i will definitly be checking the clearance.
Brian

I ran you combination thru DynoSimPro for whatever it's worth.

629 HP @ 6000
644 TQ @ 4500

Dynamic compression = 9 to 1
If one knows how to tune, it will be OK on pump gas.

The engine would like more cam and more carburetor.

Hey thanks for doing that. I appreciate it. I had told my customer 600 plus hp so i wasn't far off on my guesstimate. Its going in an 87 mustang with a C6, 2500 stall and 3.27 gears with a 26 x 10 slick. Probably a race weight around 3200 pounds. It will likely get alot more street torture than actual race track passes. It will never be on an engine dyno but he may take it to a chassis dyno some day. The ET and MPH will tell the story. I knew the cam was small but i also know the owner won't really want to touch the motor much after its in. Was shooting for tire melting tork and a high fun factor.
Brian

I think you may have lost the fun factor 150 ft/lbs ago. Now it's just a friggin' handful

short cam with 3.25 gears and 2500 converter should work well as a combination
post back when it's on the street
but do tune
do not start with a max spark advance

Part of the "TUNE" on this pump gas, 9to1 DCR FORD 502" is a tight "QUENCH". .036"-.044"

How about you convince him to buy some boss 9 heads....

i just got a message from Jegs. The cam is out of stock and has a month wait time. I could use some input here. I want one sooner, don't want a custom grind and long wait time. Just a solid flat tappet. Allready have the new lifters. Obviously i should go bigger but i'm not a pro.

http://www.compcams.com/Company/CC/cam- ... =1021&sb=2

i like the 108 LSA, prefer under .600 lift and on the shelf for quick shipping.

brian