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Mon Dec 22, 2014 6:15 pm

I have a 71 Beetle with dual solex carbs and unknown cam. The stock rock shaft is slightly off as I keep shearing pins and having issues. The engine was rebuilt before I got it, and has about 7k miles on the rebuild. I gave an Empi 1.4 rocker set and need to know what to look for when installing as I have no idea if the cam is stock or not, given the engine has a fwe added performance parts visible. Do I need new pushrods, etc.? How do I figure out the geometry for the 1.4s? Other than setting the valves and updating the wiring, headers and exhsust, I'm nwe to VW's and don't want to screw anything up.

Mon Dec 22, 2014 10:22 pm

Well good you asked, because there's some major things to consider. First, do you have high-rev springs? If not, or you're not sure, you can't install your 1.4s until you get some HD springs. There is a tool to remove the springs and re-install different ones while the heads are on the engine. While on the subject, high rev springs are usually accompanied by chromoly retainers. Second, while it is physically possible, figuring rocker geometry while the engine is in the car will be extremely difficult, not to mention taxing on your muscles. It should come out to be done properly. Third, while they may hold up in the best-case scenario, your pushrods should be upgraded to something stronger than stock. Cheapest to most expensive goes like this: steel, chromoly, aluminum. Fourth is whether you have the tools and the will to learn how to set up your rockers correctly. You'll need at least a cheapo magnetic base dial indicator, an adjustable pushrod tool, maybe two sets of feeler gauges, and a bunch of rocker side-play shims in different thicknesses. Find a thread here to learn how to set up side-play and geometry and have at it. On my last build, it took me eight hours to set up the rocker geometry and side-play. Please use a lot of patience and common sense. Those shims have high spots that should be sanded down before mocking them up.

Oh, you also need lash caps on your valve tips. Expect to drop at least $300 in all that I've mentioned. NONE of what I have suggested is overkill. These are absolute minimums.

Tue Dec 23, 2014 7:37 am

You need to find out exactly what cam you have. If you have a performance cam ground for stock 1.1 rockers and you install 1.4 rockers, everything will be over stressed and could wear out quickly or cause a catastrophic failure.

As mentioned with 1.4 rockers you need heavy duty single springs and shorter push rods.

Tue Dec 23, 2014 10:07 am

I pretty much agree with dave. check the cam you have and see just what you have.what pins are sheering off??you my be better off selling the 1.4"s and getting 1.25 or 1.3's,but you need to know aht the cam lift you have is now.you might just need to get a set of cb or scat 1.25 bolt on rockers......well nothing is bolt on.and every situation is a bit different like my spellen.

Tue Dec 23, 2014 11:51 am

Whatever "shearing pins" means, it sounds like there is actual physical interference between valve components to cause breakage. I think you need to dissassemble the heads at a minimum.

Tue Dec 23, 2014 12:21 pm

Dr OnHolliday wrote: Whatever "shearing pins" means, it sounds like there is actual physical interference between valve components to cause breakage. I think you need to dissassemble the heads at a minimum.

Rear drivers side Rocker arm is slipping off the valve and shearing the retainting clip and I end up losing a wavy washer. Only happens on one rocker arm, but it has happened several times now. Not sure if the arm is warped or the rock shaft, so figured I'd replace the entire assembly. Trading in the 1.4 for a chromosome 1.1 empi bolt on kit.