BBC rocker arm questions
#1
BBC rocker arm questions
Now that I am changing my cam in my 73 454 vert. I wanted some opinions about the rocker arms. At first I thought of just keeping my stock rockers(I am upgrading the valve springs, adding new retains etc.) but should I use roller rockers? Or how about the stamped steel with rollers on the end? Now to sound really foolish, is the stock ratio 1.5 like on a small block? I used 1.6 Crane rollers on my 350 but this an entirely different beast. It's been years since I read my How to rebuild a BBC book. I wonder where it is? Loved reading it a teenager. Using a Voodoo 60202 cam because a forum member made me a great deal on one. Thanks
Plan on keping the stock valve covers if that makes a difference. Maybe roller rockers would be to tall?
Stock studs with larger 3/8 guide plates. Plan on leaving heads on engine for cam change.
Plan on keping the stock valve covers if that makes a difference. Maybe roller rockers would be to tall?
Stock studs with larger 3/8 guide plates. Plan on leaving heads on engine for cam change.
Last edited by superdave269; 09-06-2012 at 10:21 PM.
#2
the rpm range of that cam is 1,400 to 5,700 use the roller tip rockers, use dont need full for that range, they are 1.7 ratio.
#3
Drifting
You don't need roller rockers, but there are some benefits to using them.
A roller rocker will have the correct rocker ratio, or at least a lot closer than stock rockers.
Stock rockers are known to often measure out as having a lower than spec ratio, which means less valve lift.
If you run "real" roller rockers, you will also benefit from lower friction at the rocker trunnion.
You will typically have to run thicker gaskets to clear the poly-locks that go along with full roller rockers.
Roller tip rockers will fit with no issues.
A roller rocker will have the correct rocker ratio, or at least a lot closer than stock rockers.
Stock rockers are known to often measure out as having a lower than spec ratio, which means less valve lift.
If you run "real" roller rockers, you will also benefit from lower friction at the rocker trunnion.
You will typically have to run thicker gaskets to clear the poly-locks that go along with full roller rockers.
Roller tip rockers will fit with no issues.
#5
Racer
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Plan on keping the stock valve covers if that makes a difference. Maybe roller rockers would be to tall?
I have what i think they call neddle tip roller rockers in my 69 427 with the stock valve covers
I have what i think they call neddle tip roller rockers in my 69 427 with the stock valve covers
#7
Le Mans Master
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my engine builder (a professional racer) doesn't like rollers in street engines. he told me that the extra weight of the rollers need higher spring loads that leads to increased wear. just his 50 years of experience talking.
#9
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The above is absolutely true. The geometry of a BB rocker arm at work places a tremendous lateral load on the valve guides - especially with higher than stock lifts. I found this out the hard way after considerably less than 100K miles. Roller tips are the only way to go on a BBC.
#10
The above is absolutely true. The geometry of a BB rocker arm at work places a tremendous lateral load on the valve guides - especially with higher than stock lifts. I found this out the hard way after considerably less than 100K miles. Roller tips are the only way to go on a BBC.
#11
Thanks guys. I really like the input. Especially that it is first hand info and not some urban legond. Sounds like some had good results with roller rockers and others have not. I am getting a set of Proline roller tip rocker arms, rks -454b1.7.from a forum member. Wish me luck with the project.
#12
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Proline? I don't know exactly who makes them...but I can tell you I would get a set of stock GM long slots before I'd run a cheap set of import rockers on a BBC.
Seriously I don't know about those..but I'd surely ck into them. There is some very poor quality *pretty* valvetrain pieces being imported that are just pure junk. The shafts for the rollers slip out, the aluminum cracks etc etc. Just do your homework.
JIM
Seriously I don't know about those..but I'd surely ck into them. There is some very poor quality *pretty* valvetrain pieces being imported that are just pure junk. The shafts for the rollers slip out, the aluminum cracks etc etc. Just do your homework.
JIM
#13
Yup, I hate to say it but the rockers are junk. Glad I didn't pay to much for them. We got about 30 miles on the cam swap now and broke at least 2 of the rockers. I'll run the stock GM rockers for now.
Please do your self a favor and stay away from these http://www.flatlanderracing.com/prolinetiprockers.html
The rockers were the only cheap- oh part. I do believe you get what you pay for with engine parts.
Please do your self a favor and stay away from these http://www.flatlanderracing.com/prolinetiprockers.html
The rockers were the only cheap- oh part. I do believe you get what you pay for with engine parts.
Last edited by superdave269; 09-06-2012 at 10:22 PM.
#14
Le Mans Master
FWIW, if you're in the market, I have a full set of 16 used/excellent condition factory long-slot "H" high-perf BB rockers w/grooved ***** and locks (fit w/stock covers), still matched up and kept oily.
edit - Should have a full set of factory high-perf 7/16" pushrods to go with them too.
edit - Should have a full set of factory high-perf 7/16" pushrods to go with them too.
Last edited by TheSkunkWorks; 09-06-2012 at 11:20 PM.
#15
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Hate to hear that about the rockers.....there are some high quality import stuff...but there is some total junk and there are few namebrands associated with the latter. Luckily you didn't get anymore damage.
I have a buddy with a genuine L-88 that he's had running for at least 30 years in his SS Nova. It had a larger flat tappet solid cam installed but kept the factory long slot stamped rockers and 7/16" pushrods. That sucker has been spinning 7500 rpm for years with no issues. I'd run genuine GM long slots in a heartbeat on something like this.
JIM
I have a buddy with a genuine L-88 that he's had running for at least 30 years in his SS Nova. It had a larger flat tappet solid cam installed but kept the factory long slot stamped rockers and 7/16" pushrods. That sucker has been spinning 7500 rpm for years with no issues. I'd run genuine GM long slots in a heartbeat on something like this.
JIM
#17
Burning Brakes
Is a pattern emerging
So, let me just get this straight:
"Proline Discount rockers" at $85,- tend to fail while "COMP Cams rockers" at $169,- work fine?
"Proline Discount rockers" at $85,- tend to fail while "COMP Cams rockers" at $169,- work fine?
#18
I got a good deal on the cam(still new in the box) from a forum member. Then he mentioned having a set of rockers. The rockers well not such a good deal. I should of went with my gut on these and passed on the rockers, as soon as I realized that they were a no name brand. I posted my experience to try and help anyone from making the mistake that I made. Don't cheap out on performance parts you get what you pay for.
I'm going with the stock rockers for now if I change them out in the future I'll go with the ones that 63mako posted. I'm laid off from work now so money is more than tight around here.
I'm going with the stock rockers for now if I change them out in the future I'll go with the ones that 63mako posted. I'm laid off from work now so money is more than tight around here.
#20
Burning Brakes
With just a cam change, you'll never see or feel the benefits of roller rockers....I'm running stock rockers with polylocks on mine.
Last edited by damoroso; 09-07-2012 at 09:01 AM.