z31.com

[SATAN]

Here I will explain how to make a solid lifter out of your OEM lifter while still retaining the hydraulic action of the lifter. I will also tell you how to install your lifter. This is a very tedious process and not for lazy people.

First, lets talk about hydraulic lifters and why you have them in the first place. Your Z31 comes with hydraulic lifters from the factory. The reason they are hydraulic and not solid adjustable like some other engines, (B18 B16 for example) is because they wanted them to be maintenance free. On engines with solid adjustable lifters, you have to go in and adjust the lash every so often, roughly every 15,000-20,000 miles or so. With hydraulic lifters, the lash is automatically adjusted every time the engine starts and oil flows into the lifter. "What is this "lash" that you are talking about?" Well, the lash I am talking about is the space between the lifter and the rocker arm. From the factory there should be zero lash. On a honda B series engine the lash adjustment is roughly .006"-.008". That is slightly thicker than a human hair. This lash is there because at the engine warms up, heat causes the lifter (and everything else) to expand. If you started with zero lash, once the engine warmed up, the valves would always be hanging open.

So why would you want to get rid of this self adjusting hydraulic lifter? Well, you aren't really getting rid of the hydraulic action of the lifter. you will understand as you read. Ok, well then, why even mess with the lifter, what is wrong with the way it is? Nothing, if you are running OEM cams. Once you upgrade to a higher profile cam and stronger valve springs, this puts more stress on the hydraulic lifter. If your lifters are old and worn (like most of them are) they will collapse from the stress of a heavier spring, bigger cam and higher RPM's. When your lifter collapses, it takes away from your duration and lift of the cam. This is where a solid lifter comes into play. A solid lifter will not collapse allowing you to retain your cams specs!

I am going to show you how to have BOTH!

The lifter on top is your stock lifter assembled.
The lifter on bottom is your lifter disassembled.

This is how everything fits together when inside the lifter body.


In this next picture you will see an extra piece that will be installed inside the lifter body in between the top piece and the check valve. The lifter body inside diameter is roughly .452". The shim I am using is going to be .432" in diameter. This is roughly .020" smaller than the I.D. of the lifter body. This will allow oil to get past the shim and into the check valve under it. If possible the shim should be made out of hardened steel. If not, you may have "mushrooming" of the steel over time and you will have to go in and redo the job. Now you may ask yourself "How thick does this shim need to be?" Well, that is not something I can answer for you. This is where you have actually do the measuring yourself. I started with a shim thickness of .113" I dont know if that is going to be small enough yet. If your shim is to thick, it will cause your valve to hang open all the time.

How you install your new lifter. The lifter should NOT be 100% assembled at this point. Leave the C clip out along with the spring at the bottom. You will have to make adjustments to the thickness of the shim.

Your engine should be completely cold while following these instructions. If it is not, wait till it is.
1. Assuming your valves and springs are all installed, you place your lifter into the lifter holder piece that bolts to the head (whatever that piece is called).
2. Make sure your lifter is sitting on the base circle of the cam lobe so it is at its lowest point.
3. You will need to rig up something to hold a dial indicator to tell you if your valve is opening.
4. Tighten down your rocker arms while paying attention to your dial indicator. If your dial indicator moves due to your valve opening, this means your shim is too thick, you need to remove material. Make sure to keep your shim as uniform as possible. Anything less than flat, is not acceptable.
5. Once you have finally managed to tighten down your rocker arms (always make sure you are tightening ALL THREE rocker arms equally to prevent bending the rocker arm shaft) with out your valve opening at all, you are ready to start lash adjustment.

Since there are no specifications on a hydraulic lifters lash adjustment other than zero lash, I am going to use general lash numbers of anywhere from .004" .010". This is up to you as to how loose you want them. Keep in mind the looser you keep your lash, the more you are relying on the hydraulics of the lifter to compensate.

6. Now your rocker arms should be torqued down. You should have some lash between the top piece of the lifter and the rocker arm. You will have to slide a feeler gauge in between to feel how much lash you have. If you have about .005" right off the bat, congratulations, you got it perfect. If not, keep adding very thin shims of .001" on top of your main shim, until you get it down to your desired lash of .004" - .010". In my opinion .010" is quite large. Also if the amount you need to add is .004", dont use four individual shims of .001" Try to use as few shims as possible. Also keep in mind that any shim you use in this project should be made out of hardened steel. So in this case it would be one single .004" shim to sit on top of your main shim.

Here is the lifter fully compressed. Notice the dial indicator reads 0.


And here is with the rocker arm pushed down on to the valve. Notice it reads .016". So if I wanted .006" lash. I would add a .010" shim. Keep in mind this was just a quick attempt to see where in the ball park I was. I did not use feeler gauges. When I get my actual shims, I will be using the feeler gauges.

7. Now that you have your lash adjusted in correctly, pull everything apart so you can fill your lifter with heavy oil (like 50 weight) and put the lifter back together with the spring and C clip installed.
8. This time around, when you torque down your lifter, the spring tension will keep the lifter touching the rocker arm.
9. Congratulation, now you get to do this all over again with the rest of the remaining 11 lifters. If you are creative, you can figure out a way to work on the three lifters on the same rocker shaft all at once.

The remaining .004" - .010" lash that remains should be taken up by your hydraulic check valve in the lifter body if it is working properly.

You now have hydraulic/solid hybrid lifters for your z31.

Edit: As far as finding hardened steel shims, I went here http://www.mcmaster.com/
Look under "fasteners" and look under "shims". I ended up ordering 7/16" shims that look like washers. These leave .012" clearance on the sides. I figured this would be better than the other piece I talked about that left .020".

NOTE: If ANY of this does NOT make sense to you, you should NOT be performing this modification!
_________________
Fabricator, doing what I do.

[xinxspuz]

By shimming the lifters, are you lowering the strain on the lifter hydraulics during normal operation (by not requiring the hydraulic pressure to take up as much slack), or merely providing a failsafe that keeps the lash within 'normal' (defined as 'the amount of lash that a comparable, non-hydraulic valvetrain would expect to see') specs should the lifter completely give out?
Do you have any info on how brand-new lifters handle aggressive cams & high-pressure springs? In other words, is this a cheap fix for aging lifters, or a valid modification for any engine running a non-stock valvetrain?
And, finally, how does the spring pressure of the lifter spring affect the lifter operation? Would sourcing some higher-pressure springs be a valid method of 'upgrading' the lifter to handle higher valvetrain stresses as well?
_________________
My job requires frequent showering.
"Apparently, the only signature he needed was my fist."

[SATAN]

[260DET]

Clever idea, what you are doing I think is reducing the work that the hydraulic lifter has to do, so enabling it to work more efficiently. It no longer has to 'adjust' the valve clearance by internal movement, by not moving internally it just has to hold a set amount of oil to work. No oil movement, much less chance of aeration or whatever happens when the cam demands too much of a stock lifter.

That about it? Anyway, I like it.
_________________
Richard......

[bt2s14]

That is some very good info you have provided. I was wondering how my lifters would act with the upgraded cam and valve springs, this simple mod gives you peace of mind. Offtopic question: is it a good idea to use my old lifters with a new cam? Also i have wear patterns on a few of them which is a sign that they aren't rotating while operating, should I just get new lifters all together?

Thanks..
_________________
S14 with VG30e transplant in the works.

[SATAN]

[tempestas]

nifty idea... but i've got a question... seems to me that the shim there would only put more tension on the spring, because the C-clip is not going to let the lifter "grow." Unless there is slack inside the lifter to begin with? No doubt either way this is going to make more tention and less clatter. My idea was just to simply toss the big lifter plate thingy on a lathe and take it down exactly half of what you take off the base circle of the cams when you get em turned... this would at least put it back into more stock like use on the lifters. If you think about it, if you take to much off the base circle your going to end up with lifters that can't pick up the slack fully extended.
_________________
87 bastard... was making 480whp/507tq when it wasn't rotting away in its backyard gravesite

[SATAN]

[PooFlinginMonkey]

If you float the valves, will the lifter take up the slack and push the valves into the pistons?

[tempestas]

the aluminum plate that the lifters sit in. One piece taken down flat, easy. Its what the rockers bolt to and it would lower them. And we are only talking, what... a few hundreds of an inch? But, don't get me wrong, i like your idea. I was just having a hard time picturing your lash setup, seems the lifters are gonna be full length when you put it together with or without shims.

Some girl i dated back in the day got a cam for her stang and asked me to put it in. Old 302. When i got it together (it was a hydraulic lifter motor) the lifters were full length and left enough slack to move the pushrods up and down (clicky click.) This motor had bolt down pedestals for each rocker. I was in a bind and needed to get it done... so i just took a few thousands off each pedestal till it would compress each lifter. Worked great. Remember its roughly doubled what you take off the pivot point to the clearance.
_________________
87 bastard... was making 480whp/507tq when it wasn't rotting away in its backyard gravesite

[SATAN]

[SATAN]

[PooFlinginMonkey]

One thing to consider if doing this is whether you have had any head work done that required seat resurfacing which will raise the installed height of the valve and still be within stock specifications but with the mod described above may cause there to not be enough lash.

Sounds like a good mod to me.

[SATAN]

[PooFlinginMonkey]

What I mean is that anybody having had seat grinding and just slapping this into a car could end up with zero lash or less.

My message is measure first before modding.