RHS head valve train geometry issue

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lil red said:
good to know .... my LA X had the wipe pattern just to the exhaust side of the valve stem .... I have 1.6 PRW stainless

this may sound stupid.... but could I mill the shaft groove deeper to improve this? or would that do nothing.
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I think if I were in that boat I would grab a 7/8" ball nose end mill and make a pass about .050" deeper. I'm sure that would make a significant improvement. I wouldn't want to take more than .100" though as that may put the adjuster into a really funky angle with the pushrod.

I guess the main thing I take away from this is that even though the RHS LA-X is marketed in a way that makes you believe that you can use your existing shaft rockers from your early LA heads--This is simply not the case as evidenced here. I have a set of RHS's on the way so I can do some testing. J.Rob
 
RAMM said:
I think if I were in that boat I would grab a 7/8" ball nose end mill and make a pass about .050" deeper. I'm sure that would make a significant improvement. I wouldn't want to take more than .100" though as that may put the adjuster into a really funky angle with the pushrod.

I guess the main thing I take away from this is that even though the RHS LA-X is marketed in a way that makes you believe that you can use your existing shaft rockers from your early LA heads--This is simply not the case as evidenced here. I have a set of RHS's on the way so I can do some testing. J.Rob
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thanks Ramm - exactly what i was thinking , calculated abouth .040 - .050 deeper would do it - wasn't sure what else it would affect
thanks, Jimmy
 
You can mill the pedestals flat, like the race W2 head and use offset blocks to move the shafts away from the stem. We do that all the time to clear larger springs. That will work.

Terry
 
Just told an Ebay distributor of RHS about this and he claimed ignorance...maybe he'll follow this link provided to him.
 
I heard RHS is out of the cast iron business. I'm surprised more people aren't talking about this. J.Rob
 
This very good to know. i have got some RHS heads for my engine. mine are the indy x's . i am having issues but not like that. i will keep an eye on it when i get them all together. and i am using the PRW 1.5 rocker the stainless version . so i hope i have no trouble with them. I hate to say this but thanks for this tip to watch out for.
 
I can't help but notice several comments about how bad the geometry was with Harland Sharp rockers. I have only owned 2 sets and both were great. The set on my new engine with EQ heads are spot on. Had an older set a few yrs. ago on a set of 915 J's and they were spot on too. Did I just get lucky? BTW: here's a couple pics of the sweep on my EQ's
 

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fishy68 said:
I can't help but notice several comments about how bad the geometry was with Harland Sharp rockers. I have only owned 2 sets and both were great. The set on my new engine with EQ heads are spot on. Had an older set a few yrs. ago on a set of 915 J's and they were spot on too. Did I just get lucky? BTW: here's a couple pics of the sweep on my EQ's
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No the issue was with the RHS LA-X shaft rocker heads. Not the EQ's-nice pic BTW. J.Rob
 
RAMM said:
No the issue was with the RHS LA-X shaft rocker heads. Not the EQ's-nice pic BTW. J.Rob
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Yeah I caught that the main topic is about the RHS heads so my apologies to Mal for getting off track talking about just the HS rockers. The reason I said what I said was because of Crackedback-Rob and OU812-Brian's comments of how bad HS arms are. Brian may have been refering to them when using them on RHS heads but Rob said the geometry was bad on a set of Eddy heads he had. Thanks
 
fishy68 said:
Yeah I caught that the main topic is about the RHS heads so my apologies to Mal for getting off track talking about just the HS rockers. The reason I said what I said was because of Crackedback-Rob and OU812-Brian's comments of how bad HS arms are. Brian may have been refering to them when using them on RHS heads but Rob said the geometry was bad on a set of Eddy heads he had. Thanks
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I belive the HS rockers for SHAFT setups are the worst. It looks like you have the stud type...much much different!!
 
ou812 said:
I belive the HS rockers for SHAFT setups are the worst. It looks like you have the stud type...much much different!!
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Yeah I do on these heads but my old J heads were of course shaft rockers and they were spot on like these. But that was yrs. ago so maybe things have changed with HS quality.
 
@ Fishy - You'll see a lot of previously owned sets of HS shft rockers on Ebay have been ground on and clearanced for retainer clearance - From what I know, thats one of the big issues with them.
 
Rat Patrol said:
@ Fishy - You'll see a lot of previously owned sets of HS shft rockers on Ebay have been ground on and clearanced for retainer clearance - From what I know, thats one of the big issues with them.
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Beehive springs work very nicely with my Harland Sharp rockers and no clearancing!
 
Rat Patrol said:
@ Fishy - You'll see a lot of previously owned sets of HS shft rockers on Ebay have been ground on and clearanced for retainer clearance - From what I know, thats one of the big issues with them.
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Gotcha Mal.

Locomotion said:
Beehive springs work very nicely with my Harland Sharp rockers and no clearancing!
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Yes they do. I have beehives on my EQ's. When I bought them I wasn't even thinking of how much clearance they'd add. Sure made it nice.
 
As the other threads detail - Indy bought the rights...and only some shaft mount rocker systems work with RHS heads.

Comp (who own RHS) probably sold the rights because their alloy shaft rockers are one of the types that don't work with RHS heads...along with Crane and Harland......


...all a bit embarrassing for them really.....#-o
 
Is it just me, or is there something wrong with the valve keeper in the RHS photo?
 

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Top photo looks like a check spring and a different retainer...bottom pick looks like the "real" spring and retainer combo....that's just what I see.

The valve guide can't move, so the bad geometry on the top pic would be the same whether or not a different spring/retainer combo was used.
 
Top photo looks like a check spring and a different retainer...bottom pick looks like the "real" spring and retainer combo....that's just what I see.

The valve guide can't move, so the bad geometry on the top pic would be the same whether or not a different spring/retainer combo was used.
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Thats correct Flyfish.

Also, the spring install on the bottom head is a set of Edelbrocks - the top head is the RHS.

The rocker on both occasions was the same Comp alloy shaft rockers.
 
RAMM said:
I think if I were in that boat I would grab a 7/8" ball nose end mill and make a pass about .050" deeper. I'm sure that would make a significant improvement. I wouldn't want to take more than .100" though as that may put the adjuster into a really funky angle with the pushrod.

I guess the main thing I take away from this is that even though the RHS LA-X is marketed in a way that makes you believe that you can use your existing shaft rockers from your early LA heads--This is simply not the case as evidenced here. I have a set of RHS's on the way so I can do some testing. J.Rob
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Ramm / Lil Red - I'm not sure deepening the trench will help - the issue is simply one of distance between the rocker shaft pedestals and the valve guides.

Unlike the intersecting vectors that create "off centre" sweep, this is just about horizontal distance between point A and point B

If you deepen the trench, the rocker will pivot slightly upwards in the "rest" position, - but ultimately when the rocker moves down to the horizontal plane as pictured, the distance issue will remain - and the roller tip will be off centre to almost off the valve tip at fully open.:eek:ops:

As D-Mailman indicated - IMHO the only real "fix" is to re-position the shaft pedestals further from the valve tip...or use the rockers that are known to work......

My 2c
 
The angle of the trench is different than valve angle. milling it deeper should help as it goes deeper it is moving the shaft towards the intake. May need to run longer valves also.
 
1970 La said:
The angle of the trench is different than valve angle. milling it deeper should help as it goes deeper it is moving the shaft towards the intake. May need to run longer valves also.
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It will help but is really only a slightly better bandaid, as it causes (what I believe) to be extra loading at the adjuster/pushrod interface. Just make sure you have good rockers with good pushrods and the right spring for the job. J.Rob
 
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