Re: BB roller cam recommendations
[Re: rick4106]
#2570725
10/28/18 09:04 PM
10/28/18 09:04 PM
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Joined: Jan 2003
Posts: 14,506 So. Burlington, Vt.
fast68plymouth
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 14,506
So. Burlington, Vt.
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No real benefit to limiting yourself to what’s available in a catalog.
68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123 Dealer for Comp Cams/Indy Heads
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Re: BB roller cam recommendations
[Re: AndyF]
#2579338
11/16/18 10:08 PM
11/16/18 10:08 PM
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Joined: May 2004
Posts: 1,522 Ste-Sophie, Quebec, Canada
Wedgeman
pro stock
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pro stock
Joined: May 2004
Posts: 1,522
Ste-Sophie, Quebec, Canada
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That would most likely work better than what the OP has now but my guess is that it is still 10 degrees too big. I tried a 270@050 cam in my 470 with TF heads and it was too big. That engine worked best with cams in the 260 range. The OP engine is a little smaller but has a bit more compression. My guess is the OP's engine will work best with a cam in the 260's. As a reference, Dyno Sim gives me the best numbers with a 270/276 at .050 for my 12.5cr 470.....
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Re: BB roller cam recommendations
[Re: Wedgeman]
#2579349
11/16/18 10:21 PM
11/16/18 10:21 PM
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Joined: May 2008
Posts: 1,131 Thigh-Gap Junction
@#$%&*!
New user name, Same old jerk!
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New user name, Same old jerk!
Joined: May 2008
Posts: 1,131
Thigh-Gap Junction
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As a reference, Dyno Sim gives me the best numbers with a 270/276 at .050
for my 12.5cr 470.....
Does the simulator consider head flow? Does it give different results for flat-tappet vs. roller cams?
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Re: BB roller cam recommendations
[Re: rick4106]
#2579402
11/17/18 01:08 AM
11/17/18 01:08 AM
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Joined: Jul 2013
Posts: 561 USA
B3RE
mopar
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mopar
Joined: Jul 2013
Posts: 561
USA
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Yes something in the combo is not working. My dart has a 446 with Sr heads that flow 290 and has a .557 mopar cam, speed pro pistons and a 750 carb. That car 6runs 6.60s @ 3300 A 290@.050 cam and Max Wedge port with only 446 cubes means you should be turning a lot of rpm to make power. Like ou812, I don't think it's making power on top. My first suspect when I see this is valvetrain instability, and may be why it's laying down. The bottom might be a bit soft from the big cam, but you could crutch that a bit with the converter. But, if it won't rev, that's an exercise in futility. Make sure the rocker geometry is right so the valvetrain stays stable, no matter what cam you choose to go with.
Mike Beachel
I didn't write the rules of math nor create the laws of physics, I am just bound by them.
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Re: BB roller cam recommendations
[Re: rick4106]
#2579493
11/17/18 11:51 AM
11/17/18 11:51 AM
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Joined: Jan 2003
Posts: 10,012 Frostbitefalls MN (Rocky&Bullw...
gregsdart
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 10,012
Frostbitefalls MN (Rocky&Bullw...
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If the motor is 446 cubes and has 2.19 intakes, Vizards LSA chart asks for a lobe seperation that is rather tight. 104! If a single pattern 270 @ .050 cam is ground that way, the overlap at .050 would be 62 degrees, letting the motor breath. I definately don't have enough experiance to pick a cam that is perfect here, but looking at 62 degrees overlap combined with no more than 270 @ .050 total duration in straight up will allow a resonably early intake closing of 59 degrees ATDC. Sounds logical to me. Use a 6,000 + stall minimum due to the glide, shift it at 7,000?
Last edited by gregsdart; 11/17/18 11:52 AM.
8..603 156 mph best, 2905 lbs 549, indy 572-13, alky
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Re: BB roller cam recommendations
[Re: rick4106]
#2579541
11/17/18 01:40 PM
11/17/18 01:40 PM
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Joined: Jan 2003
Posts: 15,439 Val-haul-ass... eventually
BradH
Taking time off to work on my car
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Taking time off to work on my car
Joined: Jan 2003
Posts: 15,439
Val-haul-ass... eventually
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Hs 1.5 harland sharps and max wedge port. Only made couple of passes with .650 lift 290@.050 old comp solid. 6.35@108.9.97@131 in 1/4. I don't have "the" answer for you, but can give you something to think about. My RB 452 has less compression (11.5) and standard ports, but comparable flow #s. Dwayne Porter spec'd a 265 at .050 x .650" on 108 LSA solid roller, which made peak torque at 5100 and peak HP at 6900. Your MW ports would probably push the peak torque & HP RPMs up 300-400 over mine. I don't recall what you may have for converter stall or what RPM you're willing to spin your engine, but you may be able to better predict what size cam suits your combination based on this.
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