Roller cam
Melting Slicks
Joined: Mar 2008
Posts: 2,989
Likes: 198
From: Meriden CT
There are many. The roller lobe profile can have much steeper ramps which also allow the valve to remain near max lift for longer. The roller on the lifter allows for that. The valves can open faster and remain open longer than flat tappet, and no worries about break in procedure or wiping off the lobes down the road due to lowered ZDDP in the motor oil.
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
To the poster. roller cams can use higher .050 duration numbers and still have higher vacuum and run smoother that their flat tappet counterparts
Le Mans Master
Joined: Oct 2007
Posts: 7,453
Likes: 976
From: RI, Now Franklin/Nashville TN
Not exactly true. It depends on the cams metal material. Cheap flame hardened cores are just as failure prone. Billet steel with sleeved on dizzy gears is the best. Rollers have higher spring pressure so you are wise to use higher ZDDP oils.
To the poster. roller cams can use higher .050 duration numbers and still have higher vacuum and run smoother that their flat tappet counterparts
To the poster. roller cams can use higher .050 duration numbers and still have higher vacuum and run smoother that their flat tappet counterparts
Roller cams should be broken in using the same procedure as flat tappet cams with a break in oil....Yes, the risk of failure is much less but do it right the first time and have piece of mind....And Yes the risk of failure from low ZDDP oils is VERY low but they still should be broken in............
Last edited by jb78L-82; Sep 18, 2016 at 11:19 AM.
Burning Brakes
Joined: Feb 2005
Posts: 894
Likes: 91
The quick answer is about 30 "free" (nominal) HP, we see this average number all the time on our 100% stock-appearing builds. They are all dyno-proven numbers, not estimates!
We mostly use Comp's "-8" cams which allow the use of ALL the factory peripherals, like the dist gear and fuel-pump pushrod.
On a side note here we had a major breakthrough just recently in this area on these early builds. We just finished fabricating a method to install the later stepped-nose roller cams in the early units. So far it has been such a "positive" for us I'm surprised I didn't figure it all out much earlier in my life. Was actually fairly simple in the end.
Absolutely, positively, no more need for any cam buttons OR messing with cam end-play at this stage of building mostly retro-hyd rollers. Cam-buttons/shims, etc., is all in the history books for us. (See the photo below)
(Add) There is no break-in time required on ANY roller cammed units, you can start them up and "idle" away. We do recommend "soaking" the lifters overnight to get oil into the needle-brgs however!
Thanks, Gary in N.Y.
P.S. Here's a shot of the setup, using a 400" SB, we have dynoed 2 or 3 builds now with this modification, works flawlessly. First photo shows the plate mounted, second shows gear installed, .004"/.005" end-play accomplished easily! No buttons, no timing cover work, no headaches! Just bolt these rollers together now!
We mostly use Comp's "-8" cams which allow the use of ALL the factory peripherals, like the dist gear and fuel-pump pushrod.
On a side note here we had a major breakthrough just recently in this area on these early builds. We just finished fabricating a method to install the later stepped-nose roller cams in the early units. So far it has been such a "positive" for us I'm surprised I didn't figure it all out much earlier in my life. Was actually fairly simple in the end.
Absolutely, positively, no more need for any cam buttons OR messing with cam end-play at this stage of building mostly retro-hyd rollers. Cam-buttons/shims, etc., is all in the history books for us. (See the photo below)
(Add) There is no break-in time required on ANY roller cammed units, you can start them up and "idle" away. We do recommend "soaking" the lifters overnight to get oil into the needle-brgs however!
Thanks, Gary in N.Y.
P.S. Here's a shot of the setup, using a 400" SB, we have dynoed 2 or 3 builds now with this modification, works flawlessly. First photo shows the plate mounted, second shows gear installed, .004"/.005" end-play accomplished easily! No buttons, no timing cover work, no headaches! Just bolt these rollers together now!
Last edited by GOSFAST; Sep 18, 2016 at 01:14 PM. Reason: Add info
Burning Brakes
Joined: Apr 2013
Posts: 1,194
Likes: 109
From: Las Vegas NV
Well that's nice. My stupid cam button timing cover required a smaller harmonic damper and spacers for all my accessories and stuff.
Car is fast though
Car is fast though
Last edited by AboveTheLogic; Sep 18, 2016 at 04:10 PM.
Drifting
Joined: Aug 2009
Posts: 1,346
Likes: 160
From: new iberia la
[Quote]
(Add) There is no break-in time required on ANY roller cammed units, you can start them up and "idle" away. We do recommend "soaking" the lifters overnight to get oil into the needle-brgs however!
however, on complete builds, the rings do need break-in
(Add) There is no break-in time required on ANY roller cammed units, you can start them up and "idle" away. We do recommend "soaking" the lifters overnight to get oil into the needle-brgs however!
however, on complete builds, the rings do need break-in
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Melting Slicks
Joined: Mar 2008
Posts: 2,989
Likes: 198
From: Meriden CT
Had a 1976 L-82, 4-sp
Joined: Mar 2011
Posts: 5,338
Likes: 1,213
From: Some days your the dog and some days your the hydrant.
Royal Canadian Navy
I converted to a retro hyd roller cam on an already broken-in engine. I did not do any break-in for the cam. Zero issues. The big difference in cams is that a roller lifter rolls over the cam but flat tappet lifters rub on the cam. Hence, the ZDDP requirement for flat tappets..
Drifting
Joined: Oct 2012
Posts: 1,524
Likes: 61
From: Medina Ohio
The quick answer is about 30 "free" (nominal) HP, we see this average number all the time on our 100% stock-appearing builds. They are all dyno-proven numbers, not estimates!
We mostly use Comp's "-8" cams which allow the use of ALL the factory peripherals, like the dist gear and fuel-pump pushrod.
On a side note here we had a major breakthrough just recently in this area on these early builds. We just finished fabricating a method to install the later stepped-nose roller cams in the early units. So far it has been such a "positive" for us I'm surprised I didn't figure it all out much earlier in my life. Was actually fairly simple in the end.
Absolutely, positively, no more need for any cam buttons OR messing with cam end-play at this stage of building mostly retro-hyd rollers. Cam-buttons/shims, etc., is all in the history books for us. (See the photo below)
(Add) There is no break-in time required on ANY roller cammed units, you can start them up and "idle" away. We do recommend "soaking" the lifters overnight to get oil into the needle-brgs however!
Thanks, Gary in N.Y.
P.S. Here's a shot of the setup, using a 400" SB, we have dynoed 2 or 3 builds now with this modification, works flawlessly. First photo shows the plate mounted, second shows gear installed, .004"/.005" end-play accomplished easily! No buttons, no timing cover work, no headaches! Just bolt these rollers together now!
We mostly use Comp's "-8" cams which allow the use of ALL the factory peripherals, like the dist gear and fuel-pump pushrod.
On a side note here we had a major breakthrough just recently in this area on these early builds. We just finished fabricating a method to install the later stepped-nose roller cams in the early units. So far it has been such a "positive" for us I'm surprised I didn't figure it all out much earlier in my life. Was actually fairly simple in the end.
Absolutely, positively, no more need for any cam buttons OR messing with cam end-play at this stage of building mostly retro-hyd rollers. Cam-buttons/shims, etc., is all in the history books for us. (See the photo below)
(Add) There is no break-in time required on ANY roller cammed units, you can start them up and "idle" away. We do recommend "soaking" the lifters overnight to get oil into the needle-brgs however!
Thanks, Gary in N.Y.
P.S. Here's a shot of the setup, using a 400" SB, we have dynoed 2 or 3 builds now with this modification, works flawlessly. First photo shows the plate mounted, second shows gear installed, .004"/.005" end-play accomplished easily! No buttons, no timing cover work, no headaches! Just bolt these rollers together now!
http://www.lingenfelter.com/PROD.htm...0#.V981qjMrKVM
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
I personally wiped lobes many years ago on a cheap H-roller from comp cams. The reason was I was using a dual spring idea with fairly high seat pressure that came with the heads from AFR. Last year I help R&R a 454 in a 68 vette. We used break in oil and everything, again it was the dual springs that came with the H-roller comp cam and spring kit.
We tore the 454 down and replaced the cam and removed the inner springs for the break in period and everything is fine.
Unrelated to breakin, but at the shop a customer brought in a Chevy suburban with about 85K miles on his all stock 454. GM factory H-roller on inspection nearly every cam lobe had roller wheel width tracks deep in every cam nose. So he was getting about 60% of his valve lift. It was a late 90's Suburban and maybe mid 2000 when it lost power. I think and this is when you first started hearing about EPA requiring clean oils with less lubrication factors.
I use VR-1 racing oil in both of my hot rodded roller motors
We tore the 454 down and replaced the cam and removed the inner springs for the break in period and everything is fine.
Unrelated to breakin, but at the shop a customer brought in a Chevy suburban with about 85K miles on his all stock 454. GM factory H-roller on inspection nearly every cam lobe had roller wheel width tracks deep in every cam nose. So he was getting about 60% of his valve lift. It was a late 90's Suburban and maybe mid 2000 when it lost power. I think and this is when you first started hearing about EPA requiring clean oils with less lubrication factors.
I use VR-1 racing oil in both of my hot rodded roller motors
Last edited by gkull; Sep 18, 2016 at 09:42 PM.
Melting Slicks
Joined: Jun 2016
Posts: 2,979
Likes: 332
From: Woodinville WA
The quick answer is about 30 "free" (nominal) HP, we see this average number all the time on our 100% stock-appearing builds. They are all dyno-proven numbers, not estimates!
We mostly use Comp's "-8" cams which allow the use of ALL the factory peripherals, like the dist gear and fuel-pump pushrod.
On a side note here we had a major breakthrough just recently in this area on these early builds. We just finished fabricating a method to install the later stepped-nose roller cams in the early units. So far it has been such a "positive" for us I'm surprised I didn't figure it all out much earlier in my life. Was actually fairly simple in the end.
Absolutely, positively, no more need for any cam buttons OR messing with cam end-play at this stage of building mostly retro-hyd rollers. Cam-buttons/shims, etc., is all in the history books for us. (See the photo below)
(Add) There is no break-in time required on ANY roller cammed units, you can start them up and "idle" away. We do recommend "soaking" the lifters overnight to get oil into the needle-brgs however!
Thanks, Gary in N.Y.
P.S. Here's a shot of the setup, using a 400" SB, we have dynoed 2 or 3 builds now with this modification, works flawlessly. First photo shows the plate mounted, second shows gear installed, .004"/.005" end-play accomplished easily! No buttons, no timing cover work, no headaches! Just bolt these rollers together now!
We mostly use Comp's "-8" cams which allow the use of ALL the factory peripherals, like the dist gear and fuel-pump pushrod.
On a side note here we had a major breakthrough just recently in this area on these early builds. We just finished fabricating a method to install the later stepped-nose roller cams in the early units. So far it has been such a "positive" for us I'm surprised I didn't figure it all out much earlier in my life. Was actually fairly simple in the end.
Absolutely, positively, no more need for any cam buttons OR messing with cam end-play at this stage of building mostly retro-hyd rollers. Cam-buttons/shims, etc., is all in the history books for us. (See the photo below)
(Add) There is no break-in time required on ANY roller cammed units, you can start them up and "idle" away. We do recommend "soaking" the lifters overnight to get oil into the needle-brgs however!
Thanks, Gary in N.Y.
P.S. Here's a shot of the setup, using a 400" SB, we have dynoed 2 or 3 builds now with this modification, works flawlessly. First photo shows the plate mounted, second shows gear installed, .004"/.005" end-play accomplished easily! No buttons, no timing cover work, no headaches! Just bolt these rollers together now!
A retrofit roller cam and lifters is in my future so this sounds like a dream!
Adam
Had a 1976 L-82, 4-sp
Joined: Mar 2011
Posts: 5,338
Likes: 1,213
From: Some days your the dog and some days your the hydrant.
Royal Canadian Navy
Installing a retro fit HR cam is not difficult. I used a cam button and a cam gear with a built-in torrington thrust bearing. Pretty easy!!!
Le Mans Master
Joined: May 2008
Posts: 9,063
Likes: 2,736
2022 C3 of the Year Finalist - Modified
I bring this up every time people talk about breaking in engines........do NEW car engines, the hundreds of thousands of engine produced and sold every year. i.e. Ford, Chevy, Honda, Toyota, on and on break in engines at the factory? Yes or no?
I have bought new vehicles, and read the manual, and all it says is to limit engine RPMS for the first so many miles....that's it. These are engines that routinely go 100,000 plus miles without issue.
So, so much for breaking in.
I have bought new vehicles, and read the manual, and all it says is to limit engine RPMS for the first so many miles....that's it. These are engines that routinely go 100,000 plus miles without issue.
So, so much for breaking in.
Last edited by Shovels and Vettes; Sep 20, 2016 at 08:34 PM.
Drifting
Joined: Jan 2012
Posts: 1,908
Likes: 129
From: Fredericksburg Virginia
Dunno, Mr. Iwasmenowhesgone. I recall being specifically advised when I bought my F250 with the 6.7L diesel to not do the first oil change early. That the first load of oil had a break-in additive and to keep it in for at least 5,000 miles.
This may be one of those things were it is unsaid what is in the oil from the factory, but the assumption is that you don't run home, dump the oil, and put your own oil in, being as that would be a somewhat unreasonable thing to do.
There's no warning in the manual about not driving your car with your eyes closed. But that would also be a somewhat unreasonable thing to do.
There are some things associated with owning/driving the cars that simply aren't written in the manual.
This may be one of those things were it is unsaid what is in the oil from the factory, but the assumption is that you don't run home, dump the oil, and put your own oil in, being as that would be a somewhat unreasonable thing to do.
There's no warning in the manual about not driving your car with your eyes closed. But that would also be a somewhat unreasonable thing to do.
There are some things associated with owning/driving the cars that simply aren't written in the manual.
Had a 1976 L-82, 4-sp
Joined: Mar 2011
Posts: 5,338
Likes: 1,213
From: Some days your the dog and some days your the hydrant.
Royal Canadian Navy
I've owned a few cars from new, Nissan's I think, that stated the same thing in the manual to not change the oil before xxxx miles because it was an oil that had properties for breaking in the engine.
Le Mans Master
Joined: Mar 2001
Posts: 5,738
Likes: 644
From: Lincoln, CA
Honda does the same thing. When I checked bobtheoilguy site I found a Blackstone report that it was loaded with moly.