347 cam recommendation

hi-tech cobra · #1 (**permalink**) 10-29-2006, 08:26 PM

Any suggestions on a cam for my cobra? It will be mostly street use. My goal is good torque in the lower rpm range, where I can use it.

Here's what I have:
Eagle forged 347 kit
GT-40X Heads (ported)
EB Air Gap intake
Speed Demon 650 cfm carb
Tremec TKO600 (.82 OD)

Also...is there a big differance between Ford, Comp Cams, or Crane's hydraulic roller lifters?

69 Mach I · #2 (**permalink**) 10-31-2006, 02:25 AM

Quote:

Originally Posted by hi-tech cobra

Any suggestions on a cam for my cobra? It will be mostly street use. My goal is good torque in the lower rpm range, where I can use it.

Here's what I have:
Eagle forged 347 kit
GT-40X Heads (ported)
EB Air Gap intake
Speed Demon 650 cfm carb
Tremec TKO600 (.82 OD)

Also...is there a big differance between Ford, Comp Cams, or Crane's hydraulic roller lifters?

I would choose a cam based on your your heads post-porting flow numbers. Do you know them?

KevinM · #3 (**permalink**) 10-31-2006, 06:03 AM

The Ford X and Z cams are pretty good, the others are compromised by low lift needed to work with stock heads so I would stay away from them.

I like Comp myself, but Crane is also good.

I don't know the flow and flow ratios on your heads. Many SB Ford heads have poor exhaust flow and do better with a split profile cam. Some heads (like the AFR) have good exhaust flow and would use a cam with the same lobes intake and exhaust.

Ballpark numbers: 216 to 220 degrees duration @.050 (Intake numbers if it's a split profile) and .540 to .550 lift. That would be for a 6,000 RPM engine.

Kevin

Dan Stryffeler · #4 (**permalink**) 10-31-2006, 06:42 AM

My engine builder spec'd out the Crower #15513... it comes on a little late - at 2400rpm, so pulling away from a stoplight you have to blip it a little bit to get moving off idle.

- Dan

hi-tech cobra · #5 (**permalink**) 10-31-2006, 07:14 AM

Dan,
How is the 15513 cam around town? What trans do you have? Would I need to beef up my valve train - currently it the Ford Motorsports springs, valves, etc.

Dan Stryffeler · #6 (**permalink**) 10-31-2006, 07:37 AM

Other than having to goose the car to get it really moving off idle, I like the cam around town. Most of my driving is through a couple stop lights and then down into our metroparks where the speed limit is 30mph - I run it at 35mph in 4th gear and it just tools along. Sounds boring, but the route is just a really nice run. After about 45 minutes I'm out on the rural roads where you can run 55 to 80mph up some nice hills, dips and curves - lot'sa fun.

I have a 4 sp top loader from David Kee and (as I recall) a 3:55 rear end.

Here is the parts listing, unfortunately I don't see the valve springs in the list...

Part Number Manufacturer Description

15513 Crower Hydraulic camshaft Ford 302 H.O. 228HR234
M-68HV Melling Oil pump
M-6500-R302 Ford Hydraulic tappet
15-611 (2026) Canton Small block Ford pickup for 8” deep pan
15-610 Canton Small block Ford 8” deep pan w/stiffener rails
85833 MSD Ford distributor steel gear
M-6605-A302 Ford Oil pump shaft
J100F8-4030-5 J-E S.R.P. Piston ring
100-7107 ARP Rocker stud kit
- MISC - Clevite Bearings
1332-16 Comp Cams Full roller rocker arms
TFS-51500700 Trick Flow Main support w/ARP main cap bolts
140689 J-E S.R.P Pistons
92727501551S Pins
927042CS Locks
RA4030 Rails
Ferrea Valves
430234005400 Eagle ESP 4340 Crankshaft, forged

hi-tech cobra · #7 (**permalink**) 10-31-2006, 09:42 AM

Dan,
Sounds like a nice setup. Any regrets you went with a 347? How is the power - plenty? Having done a 427so and a 289, I was inclined to take the less flash - more cash in my pocket route. The 347 seemed like the way to go for the money.

Have you dyno'd it? Carb choice?

Are you happy with the Toploader?

Dan Stryffeler · #8 (**permalink**) 10-31-2006, 10:41 AM

I'm very happy with the 347 - has a little higher oil consumption because of the stroke; (techies, feel free to correct me on this), one of the oil rings sits over the wrist pin.

It dynoed at 383 Horsepower @ 5750 rpm, 414 ft-lbs torque @ 4000 rpm. This was at the flywheel, not on a chassis dyno.

The limitations are largely due to my choice of carburation - I have a Ford Tri-power setup on it. With a more modern intake and carb choice, my builder thought it would make an easy 425hp, if not more (he likes the Weiand Stealth intake and Holleys).

The other thing he likes to do is fill up the lower water passages with some type of epoxy/iron mix which combined with a stud girdle on the main bearings strengthens the block.

Very happy with the tranny choice; it would be nice to have an OD gear, but then I think the driving experience wouldn't be the same.

tbirdz12 · #9 (**permalink**) 10-31-2006, 02:23 PM

Condiser the Comp XE274 HR . Would go nice with that setup.

69 Mach I · #10 (**permalink**) 10-31-2006, 11:53 PM

I bet some 4.11s in the back would fix your problem.