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-   -   High-lift cams, SUB, new valve job = lifter tick? (https://www.miataturbo.net/engine-performance-56/high-lift-cams-sub-new-valve-job-%3D-lifter-tick-85906/)

Der_Idiot 09-14-2015 02:35 PM

High-lift cams, SUB, new valve job = lifter tick?
 
I finished breaking in the new 10mm maruha 264 cams and the car sounds agressive and I love it. The engine however is louder than I remember it being. I have lifter tick that I can hear at 40mph with the driver's window down, over the exhaust note at 4k. Is that normal with a lift like 10mm? Tick gets louder as RPMs raise, just oil in the filter when I dissected it as well. I'm perplexed.

Changes:
New keepers
New valve seals
New cams
SUB lifters
.011-.014 cold lash

Joe Perez 09-14-2015 02:41 PM


Originally Posted by Der_Idiot (Post 1266348)
.011-.014 cold lash

Unless maruha publishes different lash specifications for their cams (never looked, too lazy to look now), this is on the loose end of spec (.011-.012) for the exhaust side, and completely out of spec (.008-.009) for the intake side.

Der_Idiot 09-14-2015 02:51 PM

The lash was set loose to allow for the seats and valves to settle as it's a new valve job, but the other big issue was supertech just didn't have the shims to get to the perfect lash measurements. Could that really account for this much noise though?

patsmx5 09-14-2015 03:23 PM


Originally Posted by Der_Idiot (Post 1266354)
The lash was set loose to allow for the seats and valves to settle as it's a new valve job, but the other big issue was supertech just didn't have the shims to get to the perfect lash measurements. Could that really account for this much noise though?

Yes, adjust your valves to spec.

y8s 09-14-2015 03:47 PM


Originally Posted by patsmx5 (Post 1266366)
Yes, adjust your valves to spec.

I think what pat means to say since obviously without the proper shims, you can't adjust shit is this:

some people actually grind down the valve stem to achieve exact shim specs. Or they grind their own shims. Or some combination of that. In other words, you might have to get the next size up and BZZRRRT on a grinder.

NiklasFalk 09-14-2015 03:54 PM

Using OTS lash caps and hoping it's good enough, huh?

My builder buy 6mm caps in bulk and grind them to whatever thickness needed, using an old mini lathe (reserved for this task).

patsmx5 09-14-2015 04:24 PM


Originally Posted by y8s (Post 1266380)
I think what pat means to say since obviously without the proper shims, you can't adjust shit is this:

some people actually grind down the valve stem to achieve exact shim specs. Or they grind their own shims. Or some combination of that. In other words, you might have to get the next size up and BZZRRRT on a grinder.

Yeap. If you can't buy the shims, but thicker ones for another application and grind them to spec, or tip the valves (grinding the stem to shorten the valve, this increases clearance). Since your clearances are too loose, tipping the valve won't fix it, you'll need thicker shims and grind them to spec if you can't buy them the correct thickness already.

One option to make it easy is just buy shims that are a bit too thick (clearances will now be too tight) and then tip the valves to get the clearances exactly how you want them. I did this on my car, just used stock shims and tipped the valves to get them exactly where I wanted them. They're all withing .0005" of each other on my car, but I built a valve grinding machine to be able to tip the valves.

Der_Idiot 09-14-2015 05:02 PM

I actually had the guy tip the valves square because the last machinist left the ends rounded. I'll have to find someone to grind down the shims because I don't want to pull the head if I can avoid it. I picked up some smaller feelers and I'm going to run the car until operating temp and check hot lash on everything tonight or tomorrow morning, then pull the cams and compare with the shims I have in there. If I'm lucky I wont have to pull the head but there was one valve that had the, if not one of the biggest shims in there already so I may have to replace it..

Der_Idiot 09-14-2015 07:26 PM

1 Attachment(s)
Spoke to SuperTech, I should be able to run 6mm caps over the valve stems instead of 5.5mm over the lifter stud and they have way more selection in the sizes I need than the 5.5mm options. Guess I'm pulling my valve cover off again! :facepalm: :party:

https://www.miataturbo.net/attachmen...ine=1442273192

Twibs415 09-14-2015 11:15 PM

just a caution. i once tried to run the lash caps not inverted on oem length valves and it didnt work as expected. the bottom of the cup would sit on the keeper and not on the tip of the valve.

Der_Idiot 09-14-2015 11:23 PM

^ That's what I was worried about, the shim bottoming out on the retainer or shims instead of on the stem. I'm going to have them ship me one of a size that I can use and see if it works. If the shim interacts with the keepers or retainer I will have to just wait for shim availability :(

ctdrftna 09-15-2015 05:28 AM

I ran 6mm caps on my setup, if the cap hits the keeper, grind down the pocket on a belt sander or lather or surface grinder.

I would never grind the top of the lash cap, they are hardened and if they are only case hardened you may grind through it leaving the metal soft where the bucket contacts.

Der_Idiot 09-15-2015 02:32 PM

3 Attachment(s)
Found the source of the problem, shim fell off of the bucket during assembly and rattled around between the bucket and keeper but held inside the bucket by the keeper so the wear is restricted to surface damage only on those two parts, nothing that sees friction.

https://www.miataturbo.net/attachmen...ine=1442341942

Good lifter for reference:
https://www.miataturbo.net/attachmen...ine=1442341942

Lifter from the #7 valve, coating worn mostly off the stem however the stem itself is physically kosher. Verified with assembly and torquing down the cam, lash was a little tight at .009 but if there was damage to the stem it would increase lash, not decrease. Wear around the sides and top is identical to the other lifters.
https://www.miataturbo.net/attachmen...ine=1442341942

Opted to reassemble and use it as-is, should have it started tonight.

Stealth97 09-16-2015 01:08 PM


Originally Posted by Der_Idiot (Post 1266773)
Found the source of the problem, shim fell off of the bucket during assembly and rattled around between the bucket and keeper but held inside the bucket by the keeper so the wear is restricted to surface damage only on those two parts, nothing that sees friction.

https://www.miataturbo.net/attachmen...ine=1442341942

Good lifter for reference:
https://www.miataturbo.net/attachmen...ine=1442341942

Lifter from the #7 valve, coating worn mostly off the stem however the stem itself is physically kosher. Verified with assembly and torquing down the cam, lash was a little tight at .009 but if there was damage to the stem it would increase lash, not decrease. Wear around the sides and top is identical to the other lifters.
https://www.miataturbo.net/attachmen...ine=1442341942

Opted to reassemble and use it as-is, should have it started tonight.

Ouch.. May want to have a close look at the lifter bore as well..

Der_Idiot 09-16-2015 09:30 PM

Lifter looks good around the top/sides, just the post is worn. Lifter bore looked good all the way down. There's also the surface damage seen on the retainer and the underside of the bucket, as well as a small amount of scoring around the inside edge of the lifter bucket from the lifter making the rounds inside the lifter/retainer assembly. Keep in mind the car only ran for at most 35 minutes over two occasions which I think helped minimize what could have been some nasty damage.

If you look, you can see how the lifter sits in the bore much like a piston, and the retainer/valvestem/keeper assembly hugs the inside of the lifter. It's almost like an Xzibit meme.


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