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ROLLER CAM LOW LIFT FLOW HEADS #2589664
12/10/18 12:42 AM
12/10/18 12:42 AM
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East Coast
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A/MP Offline OP
super stock
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I have several iron heads that are NHRA Stock Eliminator legal. Looking at the flow #'s, all fall off around .500 (+_/-) .15. Using these heads in a bracket motor, can I get the best bag for the buck by using a roller cam and taking advantage of the faster ramp speeds? The FT stocker cams are very steep and very detrimental to the lifter, cam and valve train. I also won't need to keep the factory valve spring specs. I just want to be able to maintain or exceed my present ET/MPH. A cheap, dependable bracket car.

Re: ROLLER CAM LOW LIFT FLOW HEADS [Re: A/MP] #2589680
12/10/18 01:02 AM
12/10/18 01:02 AM
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So. Burlington, Vt.
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fast68plymouth Offline
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Not exactly sure what you’re asking....... but yes, an appropriately sized roller cam would make more power than your stock lift cheater cam.


68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads
Re: ROLLER CAM LOW LIFT FLOW HEADS [Re: A/MP] #2589728
12/10/18 04:32 AM
12/10/18 04:32 AM
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Bend,OR USA
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Cab_Burge Offline
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Some thing to think about on peak flow versus maximum lift, it you buy and use a cam the has .600 lift won't the motor flow more air at .500 twice than only at .500 lift max, if the flow slows down above .500 but it is still flowing more air up until the valve reaches .500 again when it is closing ,right work
More air and fuel equals more power, correct shruggy


Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
Re: ROLLER CAM LOW LIFT FLOW HEADS [Re: A/MP] #2589781
12/10/18 12:48 PM
12/10/18 12:48 PM

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crabman173
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The older I get ( now 61) the more I see it
Compression is king and essential--ya got that everything else falls into place
Low lift flow--no worry--with a sharp valve job it is still capable of making good HP
Stocker cams? Death to valve trains only use when running class and you Must

Racing? Rollers are best but on a Mopar bracket barge a FT is soo much cheaper and with those heads just as good IMO

Good luck and remember--Have Fun

Re: ROLLER CAM LOW LIFT FLOW HEADS [Re: A/MP] #2589786
12/10/18 01:01 PM
12/10/18 01:01 PM
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PA.
pittsburghracer Offline
"Little"John
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Take a look back at the builds we did 30-40 years ago with junk parts that ran better than many of the builds guys are doing now with way better parts. Junk heads NEEDED high compression, and HUGE cams, and lots of fuel.


1970 Duster
Edelbrock headed 408
6.143@110.85 mph
9.73@135.05 mph shifting at 6700 RPM
422 Indy headed small block
5.982@112.56 mph
9.42@138.27

Livin and lovin life one day at a time




Re: ROLLER CAM LOW LIFT FLOW HEADS [Re: pittsburghracer] #2589930
12/10/18 05:30 PM
12/10/18 05:30 PM
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sweden
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1Fast340 Offline
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Originally Posted By pittsburghracer
Take a look back at the builds we did 30-40 years ago with junk parts that ran better than many of the builds guys are doing now with way better parts. Junk heads NEEDED high compression, and HUGE cams, and lots of fuel.


I also somehow get the impression that those cams where big enough to get away with stupid compression even on pumpfuel in ways that most would never even try today.

Re: ROLLER CAM LOW LIFT FLOW HEADS [Re: 1Fast340] #2589938
12/10/18 05:45 PM
12/10/18 05:45 PM
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pittsburghracer Offline
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Originally Posted By 1Fast340
Originally Posted By pittsburghracer
Take a look back at the builds we did 30-40 years ago with junk parts that ran better than many of the builds guys are doing now with way better parts. Junk heads NEEDED high compression, and HUGE cams, and lots of fuel.


I also somehow get the impression that those cams where big enough to get away with stupid compression even on pumpfuel in ways that most would never even try today.



I ran Cam 2 back then and honestly can’t remember what the octane was listed at. I know it wasn’t anything like guys are running now.


1970 Duster
Edelbrock headed 408
6.143@110.85 mph
9.73@135.05 mph shifting at 6700 RPM
422 Indy headed small block
5.982@112.56 mph
9.42@138.27

Livin and lovin life one day at a time




Re: ROLLER CAM LOW LIFT FLOW HEADS [Re: A/MP] #2590058
12/10/18 09:19 PM
12/10/18 09:19 PM
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Posts: 3,956
New York
polyspheric Offline
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One reason why high static CR worked is because with the poor port flow the cylinder was never full at high RPM.
Delayed intake valve closure as a tuning aid to modify CR is a bad idea.


Boffin Emeritus
Re: ROLLER CAM LOW LIFT FLOW HEADS [Re: Cab_Burge] #2590131
12/10/18 11:37 PM
12/10/18 11:37 PM
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Lost in Time
Iowan Offline
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Originally Posted By Cab_Burge
Some thing to think about on peak flow versus maximum lift, it you buy and use a cam the has .600 lift won't the motor flow more air at .500 twice than only at .500 lift max, if the flow slows down above .500 but it is still flowing more air up until the valve reaches .500 again when it is closing ,right work
More air and fuel equals more power, correct shruggy

I heard this thirty years ago and still think it's true. I do believe that's why the 590 cam sold for so long. And with the crappy heads and high compression goes big duration.


Have a great day
Iowan

"obsolete is neat"

Re: ROLLER CAM LOW LIFT FLOW HEADS [Re: Iowan] #2590141
12/10/18 11:55 PM
12/10/18 11:55 PM
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pittsburghracer Offline
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Originally Posted By Iowan
Originally Posted By Cab_Burge
Some thing to think about on peak flow versus maximum lift, it you buy and use a cam the has .600 lift won't the motor flow more air at .500 twice than only at .500 lift max, if the flow slows down above .500 but it is still flowing more air up until the valve reaches .500 again when it is closing ,right work
More air and fuel equals more power, correct shruggy

I heard this thirty years ago and still think it's true. I do believe that's why the 590 cam sold for so long. And with the crappy heads and high compression goes big duration.



Heck the old 750 lift roller cams were 332 duration.


1970 Duster
Edelbrock headed 408
6.143@110.85 mph
9.73@135.05 mph shifting at 6700 RPM
422 Indy headed small block
5.982@112.56 mph
9.42@138.27

Livin and lovin life one day at a time




Re: ROLLER CAM LOW LIFT FLOW HEADS [Re: Cab_Burge] #2590153
12/11/18 12:19 AM
12/11/18 12:19 AM
Joined: Apr 2004
Posts: 508
Marilla, New York
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RalleyA12 Offline
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Marilla, New York
Originally Posted By Cab_Burge
Some thing to think about on peak flow versus maximum lift, it you buy and use a cam the has .600 lift won't the motor flow more air at .500 twice than only at .500 lift max, if the flow slows down above .500 but it is still flowing more air up until the valve reaches .500 again when it is closing ,right work
More air and fuel equals more power, correct shruggy


You have to remember that on a fast rate of lift cam sometimes the lift has to be higher than the cam designer might want or need. He can't just square off the top of the lobe because the lifter would not be able to follow the profile without floating. He needs the extra lift from the lobe to "slow" the valve down so it can reverse direction and start closing without floating. This allows more dwell time at the maximum flow of your heads and hence more power.

Re: ROLLER CAM LOW LIFT FLOW HEADS [Re: pittsburghracer] #2590159
12/11/18 12:37 AM
12/11/18 12:37 AM
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West Plains, MO
DrCharles Offline
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Originally Posted By pittsburghracer
Heck the old 750 lift roller cams were 332 duration.


Seat to seat, anyway... I think the .750 roller (R286/500) was 286 @.050 which is still a lot of duration. work

Re: ROLLER CAM LOW LIFT FLOW HEADS [Re: DrCharles] #2590164
12/11/18 12:57 AM
12/11/18 12:57 AM
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Bend,OR USA
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Originally Posted By DrCharles
Originally Posted By pittsburghracer
Heck the old 750 lift roller cams were 332 duration.


Seat to seat, anyway... I think the .750 roller (R286/500) was 286 @.050 which is still a lot of duration. work
iagree up
I like to buy and use a lot of solid roller cams that have between 250 to 270 @.050 with as much lobe lift that I can get and run tighter LSA on the custom ones I have made for special motors devil grin up
An old Mopar sponsored drag racer told me years ago to focus on the first 100 Ft. of the track and the rest of the track would take care of itself. That advice has worked well for me up
Tighter LSA help the bottom end, wider LSA don't work


Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
Re: ROLLER CAM LOW LIFT FLOW HEADS [Re: DrCharles] #2590166
12/11/18 12:58 AM
12/11/18 12:58 AM
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western pennsylvania
b1dartsport Offline
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western pennsylvania
Originally Posted By DrCharles
Originally Posted By pittsburghracer
Heck the old 750 lift roller cams were 332 duration.


Seat to seat, anyway... I think the .750 roller (R286/500) was 286 @.050 which is still a lot of duration. work
Ran that cam back in the day in our Max Wedge SS/DA car. At the end of each season we had a large box full of broken battleship springs and rocker arms. But man that sucker would run!

Re: ROLLER CAM LOW LIFT FLOW HEADS [Re: b1dartsport] #2590183
12/11/18 01:16 AM
12/11/18 01:16 AM
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pittsburghracer Offline
"Little"John
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Originally Posted By b1dartsport
Originally Posted By DrCharles
Originally Posted By pittsburghracer
Heck the old 750 lift roller cams were 332 duration.


Seat to seat, anyway... I think the .750 roller (R286/500) was 286 @.050 which is still a lot of duration. work
Ran that cam back in the day in our Max Wedge SS/DA car. At the end of each season we had a large box full of broken battleship springs and rocker arms. But man that sucker would run!




I still have two of them on my shelf. One should be sent out for a regrind as I had a lifter go bad.


1970 Duster
Edelbrock headed 408
6.143@110.85 mph
9.73@135.05 mph shifting at 6700 RPM
422 Indy headed small block
5.982@112.56 mph
9.42@138.27

Livin and lovin life one day at a time




Re: ROLLER CAM LOW LIFT FLOW HEADS [Re: A/MP] #2590309
12/11/18 12:24 PM
12/11/18 12:24 PM
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Posts: 2,211
NE Ohio
DoubleD Offline
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NE Ohio
The R286 was the standard go to cam along with near 14-1 compression by using Manley pistons with aluminium rods and angle milling heavily worked 915 heads - there were several big block a-bodies running around here that were in the mid nines in the late 80's with that combo

Re: ROLLER CAM LOW LIFT FLOW HEADS [Re: A/MP] #2590332
12/11/18 01:08 PM
12/11/18 01:08 PM
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So. Burlington, Vt.
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fast68plymouth Offline
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Back when my buddy first started racing in Stock, and we were barely under the index....... finding our way........ on about the 5th cam, which was the worst one up to that point...... we thought, maybe we’re looking at the wrong area. Maybe the cam isn’t going to unleash any magic for us.
Since the one in the motor at that point was clearly the worst we had run so far(it was one of those that came from a cam grinder who was supposed to be “good with Pontiac’s”, based on a recommendation from another racer)........we decided to just stick the small UD solid lifter street/strip cam that was in the motor when it was still a street/strip car, and just see what happens.
Well, about 4 tenths and 5mph is what happened........ so we continued on our search for a better cheater cam when we saw how much difference the cam could make.

I basically agree with crabman here......... put a nice solid in it and run it.


68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads






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