My valvetrain has always been pretty noisy. Checked vavle clearence and it's correct. I've been searching and have gotten mixed answers about puting newer style Lma's in the older style H22 heads. Do they need to be shimed?

 

Mgags7? Pirate? anyone?

 

No that's only for B heads since they're essentially using the H22 lma's. The new OEM B ones come shimmed from the factory.

Using the 99+ design lma in the obd1 is questionable though. The rockers changed in the 5th gen heads. If the obd1 lma's haven't superseded to the new style, it's probably a no go. The 97-98 heads did come with the 4g lma's, but have superseded to the 99+. However the 4g catalog still lists the old style for them so maybe there's a reverse compatibility issue.

 

I've got old USDM Prelude LMAs here if anyone's got the newer style ones I can take a measurement for comparison.

I have a friend that used ITR LMAs in his OBD1 H22 build. No need to shim. If the older LMAs are interchangeable then the new ones need to be shimmed then I would say that the new LMAs in older H22 heads will also need shimming. But without actual measurements it's all guesswork.

Pirate

 

There's no shimming involved with H heads. If your friend used ITR lma's in his H22, they would've been too tall. In the case of both the B and H heads, the heights are the same between the resepective hydraulic and spring-type lma's.

Here's the B lma mega thread.

Prelude lma on the left, B16/B18c on the right. Apparently a .09" height difference.

 

lol, I remember posting in that thread now. Thanks Vig.

There's no difference between the OBD1 LMAS between Civics Integras and Preludes until you go to ITRs or 1998+ Preludes.

14820-P30-010 B16A 1.653" OAL
14820-P30-010 B18C
14820-P30-000 H22A1
14820-P30-010 H22A4

spring-style:
14820-PCB-003 1.563" OAL
14820-PCB-305 1.653" OAL

The only difference is the depth of the LMA pocket cut into the head casting for the '98+ H22As. So I would say that if you have an 1997 and earlier H22 that you can upgrade to either of the spring-style LMAs. If you use the shorter one then you need to shim it. That's the way I see it.

-P

 

It's easy enough to measure. You want at least light pressure on the base circle to keep the middle rocker from bouncing around (and making noise) and you don't want coil bind on the LMA spring. The quick and dirty is to put them in without a shim, push down the middle rocker and see if it springs back to the base circle. If it doesn't, or barely does, shim it and try again. On the nose of the cam lobe (max lift), you should be able to push the middle rocker down a bit more. btw, I've put ITR LMA's into 3 H22's (no shims). With big cams it's safer to measure everything, turn it over by hand the first time, etc.

 

Is P# 14820-PCB-003 the lma's I could use in my 94 H22. Thanks guys