Moparts

Roller rocker spacing?

Posted By: EvilScamp

Roller rocker spacing? - 03/02/14 01:28 AM

I have a 383 i'm setting up the roller rocker spacing, i know that it should be between .015 and .030 most of mine are .030 but i have 2 or 3 that are .032.
Is this to much or can i getaway without shimming them anymore?
Posted By: bwhackd34

Re: Roller rocker spacing? - 03/02/14 01:32 AM

probably be ok..but why not shim them now if you are putting thought into it just do it..I use hardened valve spring shims..I think a 301 for a small block..and they are available in .015, .030 and .060.....015's get you right where you want to be....
Posted By: EvilScamp

Re: Roller rocker spacing? - 03/02/14 01:38 AM

I'm using .015 now, does anyone make any thinner shims?
Neither Summit or Jeg's carry them.
Posted By: RapidRobert

Re: Roller rocker spacing? - 03/02/14 03:34 AM

I'd wanna get down to .015" now/with good side to side alignment on the shaft. Somebody has em
Posted By: Stanton

Re: Roller rocker spacing? - 03/02/14 04:48 AM

Screw the shims and use springs. They're good enough for everyone hemi on the planet, why not wedges!!!
Posted By: Stanton

Re: Roller rocker spacing? - 03/02/14 04:49 AM

And even if you stay with shims, .002 is nothing to lose sleep over.
Posted By: Cab_Burge

Re: Roller rocker spacing? - 03/02/14 05:09 AM

Don't forget that aluminum expands eight more time than steel so make sure that you have enough side clearances for the motor to not have rocker arm bind against the spacers I try to focus on getting the roller tip as close to the center of the valve stem as possible and once that is done I work on the side clearances on each pair. Looser is better than a tiny bit to tight
Posted By: Sinitro

Re: Roller rocker spacing? - 03/02/14 05:56 AM

As Cab said, getting the proper alignment of the roller tip to the valve stem is the challenge...
To accomplish this we do the following:

1. Use a spare head for as a mockup sample
2. Use a Dremel tool/sanding drum to modify the valve shim for the proper clearance.. For example, if U need a shim of 0.012, take a 0.015 shim and sand it down slightly
3. After setting the rockers and shims up, mount the shaft on the mockup head. Torque down the shaft, now recheck the rocker clearances they can change slightly.

This procedure allows one to optimize the rocker setup easily, and then transfers the total shaft/rockers/shims for final engine mounting.

Just my $0.05...
Posted By: EvilScamp

Re: Roller rocker spacing? - 03/02/14 04:03 PM

Thanks for the help, much appreciated!
Posted By: Stanton

Re: Roller rocker spacing? - 03/03/14 01:15 AM

Here's a trick I use.

First I check all the rocker widths, clamp widths and large spacer widths. They are usually very close to each other but I want to know what I'm working with. I use a vernier.

I then measure the center to center of the hold down bolts. Doing some math tells me how many shims I need for each pair of rockers. I mock things up to figure where I want to use the shims to get the roller over the valve. When I'm ready to start snugging things down I use 2 halves of .015" shims that I've cut in half on each pair of rockers to give me .030 clearance per pair. Sometimes you may end up with a snug pair, sometimes a loose pair - depends on who made the stuff but this method keeps things equal right across the head. If you try getting the clearance any other way it can take a lot of time as things tend to move as you loosen or tighten the hold downs. Keep in mind you're also fighting the valvesprings while you're doing this as you have to have your pushrods in place during the final assembly.

But using springs instead of spacers eliminates all that bother!
Posted By: dogdays

Re: Roller rocker spacing? - 03/03/14 08:08 PM

Cab, we've been through this. Aluminum does NOT expand 8 times more than steel.

R.
Posted By: JohnRR

Re: Roller rocker spacing? - 03/03/14 10:07 PM

Quote:

I'm using .015 now, does anyone make any thinner shims?
Neither Summit or Jeg's carry them.




Check Mancini and or Hughes for the shims . Springs are ok on ductile rockers ... well for some maybe ... I wouldn't use them on alum. body rockers if that's what you have. If you go with springs you'll want to put a shim between it and the rocker body and you still need to shim it to center the roller tip over the spring , you can't use a spring between the rocker and the stand .
Posted By: Stanton

Re: Roller rocker spacing? - 03/03/14 11:32 PM

Quote:

Springs are ok on ductile rockers ... well for some maybe ...





No problem on ANY ductile rocker. But you still want a shim an either side of the rocker to prevent wear from both the spring and the stand.

Quote:

I wouldn't use them on alum. body rockers if that's what you have.




Why not, aluminum or iron - makes no difference. Shim between the spring and rocker to prevent wear.

Quote:

If you go with springs you'll want to put a shim between it and the rocker body and you still need to shim it to center the roller tip over the spring




Absolutely.

Quote:

you can't use a spring between the rocker and the stand




Really, did this need to be stated ?!?!?!?
Posted By: JohnRR

Re: Roller rocker spacing? - 03/04/14 03:58 AM

Quote:



Really, did this need to be stated ?!?!?!?




Obviously it did because you found the need to completely dissect my post ...

the thick heavy springs cause friction side loading against the rockers and the light springs could allow the rockers to shift sideways when opening the valve.

The spring is a crutch for people too lazy to use spacers ...
Posted By: Stanton

Re: Roller rocker spacing? - 03/04/14 04:25 AM

Quote:

The spring is a crutch for people too lazy to use spacers ...




Hmmm, tell that to Tom Hoover !!!
Posted By: fourgearsavoy

Re: Roller rocker spacing? - 03/04/14 04:50 AM

The first thing I pitch in trash are the springs.Why would anybody use them when you can have a permanent positive stable system that is easy and fun to setup
Gus

Attached picture 8060950-006.jpg
Posted By: Stanton

Re: Roller rocker spacing? - 03/04/14 04:09 PM

Quote:

easy and fun to setup




You probably enjoy getting root canals done too
Posted By: GTX MATT

Re: Roller rocker spacing? - 03/04/14 05:44 PM

Quote:

fun to setup
Gus






Are you a masochist? FUN!? Everytime you get it right you put everything together and one of the inner cylinders is about .05 too tight.

Really, they need to make those hold downs fit very snugly with the studs, there's way too much play to set these up without throwing a few F bombs.
Posted By: Cab_Burge

Re: Roller rocker spacing? - 03/04/14 08:36 PM

Quote:

As Cab said, getting the proper alignment of the roller tip to the valve stem is the challenge...
To accomplish this we do the following:

1. Use a spare head for as a mockup sample
2. Use a Dremel tool/sanding drum to modify the valve shim for the proper clearance.. For example, if U need a shim of 0.012, take a 0.015 shim and sand it down slightly
3. After setting the rockers and shims up, mount the shaft on the mockup head. Torque down the shaft, now recheck the rocker clearances they can change slightly.

This procedure allows one to optimize the rocker setup easily, and then transfers the total shaft/rockers/shims for final engine mounting.

Just my $0.05...


No disrespect intentded, I wouldn't swap rocker assemblys from side to side once their set up, let alone set them up on another head and then expect them to be correct for a head that may be a different brand or casting number OP, my message is to set up the rockers for the heads your going to run and mark the assembly in a way you know which rockers go on which head Setting them up can be very challenging, I start with the two inner cylinders and then do one outer at a time, not much fun anyway you do it but it does help make the motor more efficient and the parts will last longer when done properly I need to clarify once you get the roller tip so it is in full contact with the valve stem moving it so it is centered is not a gain in performance or longivity, it just looks better In other words if you can't get it centered on any or all of them don'tworry about it, as long as the roller tip is in full contact
Posted By: fourgearsavoy

Re: Roller rocker spacing? - 03/05/14 01:25 AM

Quote:

Quote:

fun to setup
Gus






Are you a masochist? FUN!? Everytime you get it right you put everything together and one of the inner cylinders is about .05 too tight.

Really, they need to make those hold downs fit very snugly with the studs, there's way too much play to set these up without throwing a few F bombs.



Well really it's a very rewarding job when you get it done and everything feels right.The trick is to measure,mark,record then assemble.
It's WAY easier than some of the F'd up drivabilty and electrical problems I have to deal with on a daily basis at the car dealership
Gus

Attached picture 8061966-8050261-rearviewsavoy.jpg
Posted By: Sinitro

Re: Roller rocker spacing? - 03/05/14 01:56 AM

Quote:

Quote:

As Cab said, getting the proper alignment of the roller tip to the valve stem is the challenge...
To accomplish this we do the following:

1. Use a spare head for as a mockup sample
2. Use a Dremel tool/sanding drum to modify the valve shim for the proper clearance.. For example, if U need a shim of 0.012, take a 0.015 shim and sand it down slightly
3. After setting the rockers and shims up, mount the shaft on the mockup head. Torque down the shaft, now recheck the rocker clearances they can change slightly.

This procedure allows one to optimize the rocker setup easily, and then transfers the total shaft/rockers/shims for final engine mounting.

Just my $0.05...


No disrespect intentded, I wouldn't swap rocker assemblys from side to side once their set up, let alone set them up on another head and then expect them to be correct for a head that may be a different brand or casting number OP, my message is to set up the rockers for the heads your going to run and mark the assembly in a way you know which rockers go on which head Setting them up can be very challenging, I start with the two inner cylinders and then do one outer at a time, not much fun anyway you do it but it does help make the motor more efficient and the parts will last longer when done properly I need to clarify once you get the roller tip so it is in full contact with the valve stem moving it so it is centered is not a gain in performance or longivity, it just looks better In other words if you can't get it centered on any or all of them don'tworry about it, as long as the roller tip is in full contact




Cab..
The advantage of setting it up on a mockup head is to get in the ball park..
Since there are variable tolerances between heads, once the shaft/rockers are switched to the final head to be mounted and torqued down. A final tweek of a shim may be required to optimize centering the roller to the valve stem and/or to have adequate tolerance between rockers but 95% of the critical work is done..

If a tweek may be required, EZ to pull off the shaft/rockers and adjust as needed. A few times we have had some minor differences between the heads for clearances, after torqueing down the shaft..

Just my $0.05...
Posted By: can.al

Re: Roller rocker spacing? - 03/05/14 05:10 AM

..wow,lots of opinions on this one!
one of the better cam manufacturers told me i could go to
.006 but kept mine at .010
Posted By: Stanton

Re: Roller rocker spacing? - 03/05/14 06:08 AM

Harland Sharp instructions:

http://www.harlandsharp.com/instructions/7001K%20webpage.pdf
© 2024 Moparts Forums