cam?

347 · #1 (**permalink**) 10-04-2002, 11:01 PM

i have a 347 with 10.1 comp, windsor snr alloys,int flow 298 @ .600 , 309@ .700, exh 200 @ .600 209 @.700 ,4.1 diff ,tremmec
im currently running a solid flat cam 294 adv 248 @.050 560lift 110 lobes,can anbody suggest a another solid flat cam that could give me more upper rpm??

Excaliber · #2 (**permalink**) 10-05-2002, 12:27 AM

Whew! Thats a deep question. With the facts you have at hand now I'd say you need to cut to the chase and get proffesional help (for your cam, lol).

I'd be contacting a cam grinder directly, Isky or who ever, and let the pros spec that bad boy.

Ernie

Jack21 · #3 (**permalink**) 10-05-2002, 12:21 PM

CompCams, Crane, Crower, Coast High Performance (CHP), or Ford Performance Solutions (F-P-S) could offer you better advice than we could.

Mohuska · #4 (**permalink**) 10-05-2002, 12:30 PM

The more RPM the more stress you place on the cam and valve components. My 2c is that you invest in a solid roller cam. As far as specs on the cam.....it depends on what you want out of your engine...you might contact Flatlander engines at www.flatlander.com and talk to them...They do specialized cams and engines....

A Snake · #5 (**permalink**) 10-05-2002, 07:21 PM

Agreed on the roller. A lot more latitude and a lot easier on valve gear. That's why the big boys use them.....they make hp.

Andy Dunn · #6 (**permalink**) 10-05-2002, 09:17 PM

That is a toughie. I tried 3 or 4 Crane's like
364681
364761
361421

and none of them did any better than what you currently have. I then went with the last one I could find which is 361481
http://www.cranecams.com/master/apps/ford15.htm

Be warned that it is recommended for 12.5:1 compression and up. I would not consider it without a serious chat or two with Crane's tech support. You would also need to double check your springs and piston to valve clearance.

I have no idea what carb you have so I guessed 750. No idea on the manifold so I guessed VicJr. Your current engine estimates out at
HP 486@6500
TQ 439@5000

With 361481, you will actually lose HP and TQ but push RPM up another 500. It estimates out to
HP 480@7000
TQ 405@5500

Here are the two graphs

hope this info is useful

Andy

347 · #7 (**permalink**) 10-06-2002, 04:02 AM

thanks for your imput, my engine has quad 44mm idf webers,try you program with webers

750hp · #8 (**permalink**) 10-06-2002, 05:45 AM

It's more work than changing the camshaft, but I bet your motor would make a fair bit more upper rpm power if your exhaust flowed closer to 75% of your intake @ .600"

347 · #9 (**permalink**) 10-06-2002, 07:11 AM

so wouldnt you just run a cam with more exhaust duration and lift?

Excaliber · #10 (**permalink**) 10-06-2002, 07:29 AM

,,,better advice than we could,,,,,

I forgot about (no doubt among others) Andy (THE Butcher), who of course would have graphs or pics illustrating his excellent automotive advice, lol. Well done Andy, and I stand corrected guys!

Ernie

Andy Dunn · #11 (**permalink**) 10-06-2002, 09:55 AM

In the books I've read, weber's often have horsepower limitations do to airflow restriction (they can have more total area under the curves though). A 48mm weber flows around 330cfm and so I estimated that 44mm webers flow 300cfm, and if there are 8 stacks, that is 2400 total cfm. I had the cam number off by one digit above...it is 361581. Here is the picture with individual runner 44m webers. I left the picture big so it is easier to read...just click the link to see it.

HP 465 @ 7000
TQ 430 @ 5000
http://www.cobralads.com/dyno2000/347_4.gif

Like members mentioned above, it would be best to call and talk to Comp, Crane, Isky, Lunati, or your favorite cam maker's tech support for this type of swap. It is on the radical side and I am not sure what the streetability level would be.

hope this helps

Andy

coyled · #12 (**permalink**) 10-06-2002, 10:10 AM

I would go solid roller. A roller will allow a steeper ramp which will keep your low end and give you more power up high. You get the benefit of the lift(everywhere) without the penalty of more duration(less low end). With only 10 to 1' compression, I would be careful with going to big if low end is a concern. Also, as stated, easier on the valve train. scott

Jack21 · #13 (**permalink**) 10-06-2002, 11:41 AM

One of the questions you need to ask the cam tech folks is the applicability of their particular solid roller lifter for street use. Most solid rollers are race only items.

Comp Cams introduced a redesigned solid roller lifter for street use for the small block Chevy. This was awhile back, and Comp may have these for small block Fords now. But you'd better ask.

cobrashoch · #14 (**permalink**) 10-06-2002, 10:58 PM

Have you tried retarding the cam a couple of degrees? Another thing you can do is change the exaust rockers to a longer ratio. Of course you will have to check spring bind and valve/piston clearance to. I don't know my sb fords that well like these guys do but that 110 degree lobe center seems to be wild for a 10 to one motor. Chime in guys, but at that comp. ratio I'd bet that less overlap would unload the motor and it would run better and even be more civilized. A .6 lift solid lifter cam is the most I would run any small block motor on the street. To go any higher on solids will get you very increased cam wear to my way of thinking because the ramps would need to be too steep. In any rate the roller advice is sound, if you can afford the bucks. A roller will give your engine instant snap that you don't have now I'd bet. I'm a old Crain guy myself but I think the real smart guys would at least look at what Comp cams is doing. Make a phone call to those guys tech lines. That 2$ call will most likely save your motor I'd bet.
cobrashock