as35thss

Hey all. I am installing some 1.7 non adjustable Yella Terra rockers. I have AFR 59cc heads with 7.40 push rods and 921 comp springs. The direction that came with the rocker said you should have .060 between the rocker and the retainer. I have .030. I E-mailed Yella Terra about this and I haven't recieved a response yet. I called Crane and they said .040 was good and I called AFR. They said they have motors out there running .018 to .020. Is there a true spec on this?

I am just trying to see if there is a true spec on this and if .030 is ok. Or should I use the shims which are .050 and move them up and get longer push rods. By the way the wipe is right in the middle on the valve. Any help out there?
Thanks

as35thss

Anyone?

LS1MCSS

iTrader: (18)

If you have .030 and the wipe pattern is in the middle, I say go for it. If you move the rocker up with shims, then the wipe pattern won't be right and you'll have problems later down the road.

vettenuts

iTrader: (4)

That's the first question, did you verify the wipe pattern. I have AFR's and they had more clearance but I spent a lot of time getting the wipe pattern correct. In the end, my shim was 0.125" so it increased the clearance you are looking at quite a bit.

as35thss

I do have a very good wipe pattern, with 1/2 to 3/4 turn. It took that thickness shim to get your wipe pattern correct vettenuts. What size push rod did you end up with?

vettenuts

iTrader: (4)

The YT instructions are horrible and I'm being kind. Here is a link to how I did mine. Link

Make sure the wipe is good then measure for pushrods and check clearances. Wipe is not set by pushrod length of number of turns on the bolt. The YT instructions include how to install fully adjustable rockers too and the whole thing is confusing.

as35thss

That link is great vettenuts. It doesn't answer my question. How much clearance is acceptable between the rocker and the retainer. This is what I need to know. My wipe is perfect. The clearance between the rocker and the retainer at 0.030 is my concern.

Russ K

iTrader: (1)

I just followed your procedure on my TFS 215 heads. Without any shims, the wipe pattern was towards the intake side of the valves. The supplied shims centered the wipe. Then after installing the heads with .040 Cometic gaskets, the recommended 7.5 pushrods were too short (loose). After checking the wipe pattern with the valve springs on, the wipe pattern was now towards the exhaust side of the head. So, I removed the shims and now I have 3/4-1 turn lifter preload, and the wipe pattern is now centered. So the 160 lb seat pressure springs caused the YT rocker arms to slightly flex that didn't show up using the checker springs.

I'll measure the retainer to spring clearance when I get back to the shop on Monday, but it looked ok with the 1.300 od springs.

Russ Kemp

as35thss

It is a good thing to know. You don't want the rocker hitting the retainer. I have heard 0.012 to 0.040 is ok from different threads I have read. I am at 0.030. By that I should be ok. I just want to know the spec on this. If I am to close I can install the shims and get longer push rods. I would think there is a spec out there some where.

Russ K

iTrader: (1)

Just checked the clearance between the retainer & rocker arm. I have over .060 with the valves closed, but my valve angle is 13.5* vs 15* on the AFR heads.

If your at .030, and your valve tip wipe is correct, then your OK. Did you check the valve wipe with the valve springs, or the checking springs?

Russ Kemp

vettenuts

iTrader: (4)

Russ,

I wouldn't think the rockers would flex enough to alter the wipe pattern and if they did I would think they would move back towards the intake side. Did you rotate the rockers with your hand when you initially set the wipe? Point of curiosity on my part.

To the OP, I have been running my AFR's with the YT's and a correct wipe pattern without issue.

Russ K

iTrader: (1)

Yes, I checked the wipe using checking springs with the heads on the bench. Set the dial indicator & rotated the intake rocker to .600 valve lift & then the exhaust rocker to .610 valve lift (I have the G5X3 cam). The wipe pattern was towards the intake side of the head, installing the supplied shims centered the wipe pattern. Once the heads were on the car with the valve springs installed, the wipe pattern was towards the exhaust side of the head. Removing the shims then centered the wipe & corrected the lifter preload.

Did you ever check your wipe pattern with the heads & valve springs on the engine?

Russ Kemp

vettenuts

iTrader: (4)

I think I checked them with the solid lifters and zero lash on the adjustable pushrod, never check them once the hydraulic lifters went back in because of the bleed down issue.

as35thss

I checked the wipe with with the springs on the car. One thing I don't like either is the rocker moves up and down alot on the bolt. I rechecked my wipe and think I am closer to the intake side and I have a wide wipe. So I tried one shim and the wipe moved down a bit, but still is wide. So I tried two shims and it is in the center and the wipe is much smaller. Thanks to vettenuts for his thread on this. It helped alot.

I did notice it does very a little if you push the rocker up or down and tighten it down. It doesn't seem you can get them the same on each hole.I don't like that at all. With two shims I have over 0.060. That issue is resolved.

Now I hope I don't have valve cover issues. I ordered a Comp push rod length checker. I am a little bummed I have to by longer push rods.