Roller rocker comparison
Thread Starter
Racer
Joined: Mar 2016
Posts: 470
Likes: 31
From: Melbourne Victoria
Roller rocker comparison
Hi all,
Doing some work to my stock 350 over the next few months.
Build is as follows.
Patriot exhaust headers (Already installed)
XE268H Comp cam
Edelbrock Performer 2101 inlet manifold
Upgraded valve springs and pushrods
Quadrajet carby
Stock converter (2500rpm Hi stall converter installed later)
Roller rockers 1.5 ratio
Stock heads and engine
Only thing I need to buy is the roller rockers. I've got 5 in mind.
Comp cams High energy Aluminium roller rockers. Cost $300AU landed
http://www.ebay.com.au/itm/262571455...%3AMEBIDX%3AIT
PRW Aluminium Pro Series rocker arms self aligning.Cost $340AU landed
http://www.ebay.com.au/itm/131875994...%3AMEBIDX%3AIT
Elgin stainless rocker arms ( these look quite good with a extra large trunnion and very good value for money) Cost 230AU landed
http://www.ebay.com.au/itm/261462891...%3AMEBIDX%3AIT
Comp cams Magnum roller rocker arms self aligning. No Polylocks. Cost $300 landed
http://www.ebay.com.au/itm/150782159...%3AMEBIDX%3AIT
Blumax aluminium roller rocker arms. Cost $315 landed
http://www.ebay.com.au/itm/381219586...%3AMEBIDX%3AIT
All these rockers arm are either for 3/8 or 7/16 stud. I'm not sure which size stud my stock heads will take, presuming they are a 3/8 stud. Could someone tell me what exactly size stud I need rockers for and therefore which studs I need to buy please?
Doing some work to my stock 350 over the next few months.
Build is as follows.
Patriot exhaust headers (Already installed)
XE268H Comp cam
Edelbrock Performer 2101 inlet manifold
Upgraded valve springs and pushrods
Quadrajet carby
Stock converter (2500rpm Hi stall converter installed later)
Roller rockers 1.5 ratio
Stock heads and engine
Only thing I need to buy is the roller rockers. I've got 5 in mind.
Comp cams High energy Aluminium roller rockers. Cost $300AU landed
http://www.ebay.com.au/itm/262571455...%3AMEBIDX%3AIT
PRW Aluminium Pro Series rocker arms self aligning.Cost $340AU landed
http://www.ebay.com.au/itm/131875994...%3AMEBIDX%3AIT
Elgin stainless rocker arms ( these look quite good with a extra large trunnion and very good value for money) Cost 230AU landed
http://www.ebay.com.au/itm/261462891...%3AMEBIDX%3AIT
Comp cams Magnum roller rocker arms self aligning. No Polylocks. Cost $300 landed
http://www.ebay.com.au/itm/150782159...%3AMEBIDX%3AIT
Blumax aluminium roller rocker arms. Cost $315 landed
http://www.ebay.com.au/itm/381219586...%3AMEBIDX%3AIT
All these rockers arm are either for 3/8 or 7/16 stud. I'm not sure which size stud my stock heads will take, presuming they are a 3/8 stud. Could someone tell me what exactly size stud I need rockers for and therefore which studs I need to buy please?
Last edited by Corvetteoz; Nov 28, 2016 at 09:55 PM.
Le Mans Master
Joined: Apr 2011
Posts: 6,284
Likes: 1,171
From: Hermosa
Comp cams Magnum roller rocker arms self aligning. No Polylocks. Cost $300 landed
http://www.ebay.com.au/itm/150782159...%3AMEBIDX%3AIT
I used these on the first iteration of my build. It says they are good for 350 lbs of open pressure. It's more like 300 lbs. I was running 330# open and it blued the pivot points and wore them out quickly creating excessive rocker lash. Otherwise I liked them. No guide plates needed with the self aligning ones.
3/8" studs are fine for the spring pressure these will run.
These will also fit just fine under stock valve covers.
Some of the aluminum rockers are pretty thick and may interfere with stock rocker covers unless you get a spacer for them.
http://www.ebay.com.au/itm/150782159...%3AMEBIDX%3AIT
I used these on the first iteration of my build. It says they are good for 350 lbs of open pressure. It's more like 300 lbs. I was running 330# open and it blued the pivot points and wore them out quickly creating excessive rocker lash. Otherwise I liked them. No guide plates needed with the self aligning ones.
3/8" studs are fine for the spring pressure these will run.
These will also fit just fine under stock valve covers.
Some of the aluminum rockers are pretty thick and may interfere with stock rocker covers unless you get a spacer for them.
Last edited by REELAV8R; Nov 29, 2016 at 11:54 AM.
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
Put these on your short list. I have had mine for like 20 years. No issues.
https://www.summitracing.com/int/par...4-16/overview/
https://www.summitracing.com/int/par...4-16/overview/
Thread Starter
Racer
Joined: Mar 2016
Posts: 470
Likes: 31
From: Melbourne Victoria
Comp cams Magnum roller rocker arms self aligning. No Polylocks. Cost $300 landed
http://www.ebay.com.au/itm/150782159...%3AMEBIDX%3AIT
I used these on the first iteration of my build. It says they are good for 350 lbs of open pressure. It's more like 300 lbs. I was running 330# open and it blued the pivot points and wore them out quickly creating excessive rocker lash. Otherwise I liked them. No guide plates needed with the self aligning ones.
3/8" studs are fine for the spring pressure these will run.
These will also fit just fine under stock valve covers.
Some of the aluminum rockers are pretty thick and may interfere with stock rocker covers unless you get a spacer for them.
http://www.ebay.com.au/itm/150782159...%3AMEBIDX%3AIT
I used these on the first iteration of my build. It says they are good for 350 lbs of open pressure. It's more like 300 lbs. I was running 330# open and it blued the pivot points and wore them out quickly creating excessive rocker lash. Otherwise I liked them. No guide plates needed with the self aligning ones.
3/8" studs are fine for the spring pressure these will run.
These will also fit just fine under stock valve covers.
Some of the aluminum rockers are pretty thick and may interfere with stock rocker covers unless you get a spacer for them.
http://www.compperformancegroupstore...ct_Code=981-16
According to the summit listing these have a spring rate of 370 lbs/in. Is spring rate the same as open spring pressure?
I would like to stick with my original valve covers and am happy to use a 5/16 gasket for clearance if I have to. But if they dont fit well I'll have to change the valve covers then.
https://www.summitracing.com/int/par...1-16/overview/
Put these on your short list. I have had mine for like 20 years. No issues.
https://www.summitracing.com/int/par...4-16/overview/
https://www.summitracing.com/int/par...4-16/overview/
Last edited by Corvetteoz; Nov 29, 2016 at 09:53 PM.
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 used them with a cc 280 magnum ft and currently with a Howard's retro roller 280*, .560" lift. AFR 195 heads. Spring pressure open/closed 340/160, I think. They come with springs suited for hyd roller cams. The energizer rockers are good for 450 lbs open spring pressures.
They fit under my oem finned vv covers on stock L-82 heads using two Mr. Gasket Ultra Seal gaskets. On the AFR 195's, only one gasket required, Felpro rubber/steel insert. No mods required to the internal baffles either.
They fit under my oem finned vv covers on stock L-82 heads using two Mr. Gasket Ultra Seal gaskets. On the AFR 195's, only one gasket required, Felpro rubber/steel insert. No mods required to the internal baffles either.
Last edited by resdoggie; Nov 30, 2016 at 09:54 AM.
Thread Starter
Racer
Joined: Mar 2016
Posts: 470
Likes: 31
From: Melbourne Victoria
I used them with a cc 280 magnum ft and currently with a Howard's retro roller 280*, .560" lift. AFR 195 heads. Spring pressure open/closed 340/160, I think. They come with springs suited for hyd roller cams. The energizer rockers are good for 450 lbs open spring pressures.
They fit under my oem finned vv covers on stock L-82 heads using two Mr. Gasket Ultra Seal gaskets. On the AFR 195's, only one gasket required, Felpro rubber/steel insert. No mods required to the internal baffles either.
They fit under my oem finned vv covers on stock L-82 heads using two Mr. Gasket Ultra Seal gaskets. On the AFR 195's, only one gasket required, Felpro rubber/steel insert. No mods required to the internal baffles either.
https://www.summitracing.com/int/par...2-16/overview/
But for the sake of only an extra $60US or $90AU maybe I might be better off getting the roller rockers you suggested.
https://www.summitracing.com/int/par...4-16/overview/
Do these come in a self aligning rocker, doesn't look like it? Any chance these can fit under the standard Corvette valve covers with the polylocks?
Last edited by Corvetteoz; Nov 30, 2016 at 10:17 AM.
Le Mans Master
Joined: Apr 2011
Posts: 6,284
Likes: 1,171
From: Hermosa
I might need something better than them then. With the cam I'm putting in which is the comp cam XE268H, comp cam recommend to upgrade to these valve springs.
http://www.compperformancegroupstore...ct_Code=981-16
According to the summit listing these have a spring rate of 370 lbs/in. Is spring rate the same as open spring pressure?
I would like to stick with my original valve covers and am happy to use a 5/16 gasket for clearance if I have to. But if they dont fit well I'll have to change the valve covers then.
https://www.summitracing.com/int/par...1-16/overview/
I wonder how much valve spring pressure they tolerate. Are you using these with the standard valve springs and what cam installed please mate? I've used Crane stuff before and had no issues also.
http://www.compperformancegroupstore...ct_Code=981-16
According to the summit listing these have a spring rate of 370 lbs/in. Is spring rate the same as open spring pressure?
I would like to stick with my original valve covers and am happy to use a 5/16 gasket for clearance if I have to. But if they dont fit well I'll have to change the valve covers then.
https://www.summitracing.com/int/par...1-16/overview/
I wonder how much valve spring pressure they tolerate. Are you using these with the standard valve springs and what cam installed please mate? I've used Crane stuff before and had no issues also.
If you know the spring pressure at the installed height you can compute the open spring pressure if you know the spring rate (lbs/in) and the lifted height of the valve.
The lifted height of the valve can be computed by taking the lobe lift and multiplying it by your rocker ratio. 1.5 if using standard rocker ratio or 1.6 if using those.
Comp cams lists the valve lift as such with 1.5rr.
Max Lift w/ 1.5RR: .477" / .480"
That comes out to 177.6 lbs. This is the amount the spring pressure will rise from the seat pressure or closed position of the valve.
Typical on a flat tappet may be in the 80lb to 100lb range for seat pressure.
so say it's 100lbs. 100+177.6=277.6 lbs. That is your open pressure.
To compute your lobe lift on the cam take the valve lift and divide it by 1.5.
.477/1.5=.318 cam lobe lift
.480/1.5=.320 cam love lift
Now with those numbers you can compute your valve lift with any other ratio of rocker. Like 1.6's if you want.
Then with the new valve lift you can compute your new open spring pressure.
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Dr. Detroit
Joined: Mar 2012
Posts: 10,097
Likes: 4,027
From: New Braunfels Texas
Harland sharp still some of the best on the market and is what I run at $300 a set......
https://www.summitracing.com/parts/csp-s1001/overview/
I do recommend you go to 7/16 stud......this gives you room to grow in the future.....
Jebby
https://www.summitracing.com/parts/csp-s1001/overview/
I do recommend you go to 7/16 stud......this gives you room to grow in the future.....
Jebby
Thread Starter
Racer
Joined: Mar 2016
Posts: 470
Likes: 31
From: Melbourne Victoria
I used them with a cc 280 magnum ft and currently with a Howard's retro roller 280*, .560" lift. AFR 195 heads. Spring pressure open/closed 340/160, I think. They come with springs suited for hyd roller cams. The energizer rockers are good for 450 lbs open spring pressures.
They fit under my oem finned vv covers on stock L-82 heads using two Mr. Gasket Ultra Seal gaskets. On the AFR 195's, only one gasket required, Felpro rubber/steel insert. No mods required to the internal baffles either.
They fit under my oem finned vv covers on stock L-82 heads using two Mr. Gasket Ultra Seal gaskets. On the AFR 195's, only one gasket required, Felpro rubber/steel insert. No mods required to the internal baffles either.
Seems the polylocks are the biggest problem for the bulkier rockers.
The lbs/inch is not the same as open lbs. The shop can measure the pressure at the installed height of the valve. maybe 1.9" then they can compress the spring the amount of lift of the valve or you can compute it.
If you know the spring pressure at the installed height you can compute the open spring pressure if you know the spring rate (lbs/in) and the lifted height of the valve.
The lifted height of the valve can be computed by taking the lobe lift and multiplying it by your rocker ratio. 1.5 if using standard rocker ratio or 1.6 if using those.
Comp cams lists the valve lift as such with 1.5rr.
So take your .480 and multiply it by the spring rate of 370.
That comes out to 177.6 lbs. This is the amount the spring pressure will rise from the seat pressure or closed position of the valve.
Typical on a flat tappet may be in the 80lb to 100lb range for seat pressure.
so say it's 100lbs. 100+177.6=277.6 lbs. That is your open pressure.
To compute your lobe lift on the cam take the valve lift and divide it by 1.5.
.477/1.5=.318 cam lobe lift
.480/1.5=.320 cam love lift
Now with those numbers you can compute your valve lift with any other ratio of rocker. Like 1.6's if you want.
Then with the new valve lift you can compute your new open spring pressure.
If you know the spring pressure at the installed height you can compute the open spring pressure if you know the spring rate (lbs/in) and the lifted height of the valve.
The lifted height of the valve can be computed by taking the lobe lift and multiplying it by your rocker ratio. 1.5 if using standard rocker ratio or 1.6 if using those.
Comp cams lists the valve lift as such with 1.5rr.
So take your .480 and multiply it by the spring rate of 370.
That comes out to 177.6 lbs. This is the amount the spring pressure will rise from the seat pressure or closed position of the valve.
Typical on a flat tappet may be in the 80lb to 100lb range for seat pressure.
so say it's 100lbs. 100+177.6=277.6 lbs. That is your open pressure.
To compute your lobe lift on the cam take the valve lift and divide it by 1.5.
.477/1.5=.318 cam lobe lift
.480/1.5=.320 cam love lift
Now with those numbers you can compute your valve lift with any other ratio of rocker. Like 1.6's if you want.
Then with the new valve lift you can compute your new open spring pressure.
I love learning about this stuff.Harland sharp still some of the best on the market and is what I run at $300 a set......
https://www.summitracing.com/parts/csp-s1001/overview/
I do recommend you go to 7/16 stud......this gives you room to grow in the future.....
Jebby
https://www.summitracing.com/parts/csp-s1001/overview/
I do recommend you go to 7/16 stud......this gives you room to grow in the future.....
Jebby
Thread Starter
Racer
Joined: Mar 2016
Posts: 470
Likes: 31
From: Melbourne Victoria
Yeah they're probably in front at this stage as they are inexpensive and are recommended by Comp cams together with the valve springs. The only apprehension I have about them is that they're not a full roller. But in saying that my engine isn't going to be overly worked either. The next stage of work will probably be the change to aluminium heads.
Racer
Joined: Apr 2016
Posts: 493
Likes: 65
I just finished my LS-5 big block build. I used Crane Energizer 1.7 rockers. They have a little bit shorter locks, and almost fit in a medium height cover.
I know this is a big block, and yours is a small block. I put these rockers on a few years ago, before the rebuild. I was very happy with them.
I know this is a big block, and yours is a small block. I put these rockers on a few years ago, before the rebuild. I was very happy with them.
Thread Starter
Racer
Joined: Mar 2016
Posts: 470
Likes: 31
From: Melbourne Victoria
I just finished my LS-5 big block build. I used Crane Energizer 1.7 rockers. They have a little bit shorter locks, and almost fit in a medium height cover.
I know this is a big block, and yours is a small block. I put these rockers on a few years ago, before the rebuild. I was very happy with them.
I know this is a big block, and yours is a small block. I put these rockers on a few years ago, before the rebuild. I was very happy with them.
Racer
Joined: Apr 2016
Posts: 493
Likes: 65
Thread Starter
Racer
Joined: Mar 2016
Posts: 470
Likes: 31
From: Melbourne Victoria
Wow that's some serious ponies you got there. I'll be happy if I can just spin the wheels from a stand start, can't do that at the moment. Never a good thing when you have a V8 that can't spin the wheels.
Last edited by Corvetteoz; Nov 30, 2016 at 09:15 PM.
Racer
Joined: Apr 2016
Posts: 493
Likes: 65
I think my biggest advice would be to not over-cam it. I see way too many that want a lumpy idle, get a big lift, and big duration, and the motor won't do crap.
I have Brodix heads, I put a Comp Cam roller cam, about .540 lift or so. The range on the cam is idle to 5500. Has a smooth idle and will fry the tires at rolling at 25-35 easy. I haven't had it out yet, the brake booster isn't working, and replacement is coming in a few day.
Thread Starter
Racer
Joined: Mar 2016
Posts: 470
Likes: 31
From: Melbourne Victoria
The cam I've chosen is suitable for what I need I think, especially as it's a stock engine. Going on previous comments it seems this cam will be a nice combination with the other things I'm doing. Also gives me scope to improve with some new heads later down the track.
Here's a link to the cam I'm using and dyno results with Dart SR heads. Not huge lift by any means. Max Lift w/ 1.5RR: .477" / .480"
http://www.compcams.com/v002/Pages/388/XE268H-10.aspx
Here's a link to the cam I'm using and dyno results with Dart SR heads. Not huge lift by any means. Max Lift w/ 1.5RR: .477" / .480"
http://www.compcams.com/v002/Pages/388/XE268H-10.aspx
Racer
Joined: Apr 2016
Posts: 493
Likes: 65
The cam I've chosen is suitable for what I need I think, especially as it's a stock engine. Going on previous comments it seems this cam will be a nice combination with the other things I'm doing. Also gives me scope to improve with some new heads later down the track.
Here's a link to the cam I'm using and dyno results with Dart SR heads. Not huge lift by any means. Max Lift w/ 1.5RR: .477" / .480"
http://www.compcams.com/v002/Pages/388/XE268H-10.aspx
Here's a link to the cam I'm using and dyno results with Dart SR heads. Not huge lift by any means. Max Lift w/ 1.5RR: .477" / .480"
http://www.compcams.com/v002/Pages/388/XE268H-10.aspx
You're just gonna have to put a sound bite when it's running
Thread Starter
Racer
Joined: Mar 2016
Posts: 470
Likes: 31
From: Melbourne Victoria
I'm not familiar with what you mean by sound bite??