Any experience with Jims Shovelhead Tappet Kit?

[confab]

Apparently it re-engineers oiling for the top end and oils similar to an automobile.

The Part:

http://www.jimsusa.com/pdf/instruction-sheets/1046-IS.pdf

https://www.amazon.com/JIMS-SHOVELHEAD-CLEAN-UP-KIT-1046/dp/B000GV0L70

The claims:

Shovelhead owners, "clean up your act," with JIMS®newvalve train kit. This totally re-engineered valve train kitwill enable you to oil your Shovelhead top end like anEVO.

You can remove your top end oil lines because oilis fed through JIMS®proven Powerglide tappets, thenup through work saver pushrods into JIMS®RollerRocker Arms. Tappets maintain oil pressure better, andthey improve the lubrication because oil is now pressur-ized through the points of contact.

Oil pressure to thetop end is controlled just like the proven EVO oil system.This kit comes with super special Powerglide™ tappets with an EVO style pushrod seat, special worksaver pushrods, chrome tappet blocks, two tappet block gaskets, and an easy to follow instruction sheet

Thoughts?

[JBinNC]

Jim's hydraulic tappets have a very uneven service record. Their early offerings for shovels were not very good (I had two sets when they first came out, neither set worked properly in two different motors.) Now their quality has deteriorated again;I would steer clear of them.

Jim

[confab]

Understood..

Thank you.

My cam, lifters and blocks are all worn. The pushrods have been vice gripped and look like junk. I'm sure they aren't straight.

Any products experienced builders recommend?

[Dragstews]

http://shop.velvatouchlifters.com/

And a set of .....



S&S Forged Roller Rocker Arms for 1966-1984 Harley Shovelhead ..

[confab]

Those are interesting.. One place I did have wear I could see with the naked eye when pulling the heads off were the valve tips.


Is the EVO oil scheme superior on a shovelhead?

[Dragstews]

Take a photo and post it...

All of us like to look ....

[confab]

...

[confab]

For the 383 Vettes, I've seen some really good engine builders use adjustable pushrods to lock in a pushrod length before ordering.

They will mark the valve stem and make minute adjustments in the rod length till the pattern is good and is center of the valve.

I don't know why this wouldn't apply to Harleys also? Because it looks like there's a good deal of scrubbing there and maybe a geometry problem, even if the lash is okay.

Thoughts?

[JBinNC]

Rocker pad and valve tip wear look completely normal. Ideally the valve does rotate a little in service, so the wear will be all over it, no problem.

The reason you don't use adjustable or select fit pushrod lengths in a shovel is that the rocker arm axis is fixed, and the pushrod adjustment is how you adjust the valves. On the Chebby, you are varying the pushrod length to set the position of the rocker arm fulcrum. (On the shovel, you can change the rocker shaft position by shimming the rocker box up, or decking its gasket surface to bring it down.) Pad contact is usually varied by changing the installed height of the valve, the valve stem length (with a custom valve) or by using valve lash caps. BUT, shovels are very forgiving of rocker arm geometry and you won't find much problem at under .600 valve lift.

Jim

[JBinNC]

Understood..

Thank you.

My cam, lifters and blocks are all worn. The pushrods have been vice gripped and look like junk. I'm sure they aren't straight.

Any products experienced builders recommend?

I'm gonna try to address this question, but it might get a little long. Tappets have been discussed ad nauseam on the Shovelhead Forum, you should go there and look back through the "Engine" threads. And do try to join if you are not already a member. Hard to do, but new members occasionally slip past the goalie.

[JBinNC]

OK, as of June, 2019, here's what's available, as far as I know:

For aftermarket hydraulic tappets, VelvaTouch is the top shelf product $$$. BUT, Dave is only making evo cam conversion sets for shovels now, so you also need an evo cam.

Next, for hydraulic tappets, is the S&S evo conversion kit $$$$$. Comes with everything, but I have paid less for complete shovelhead MOTORCYCLES!

Jim's hydraulic tappets we have already touched on, very uneven quality control. But, Jim's makes a beautiful set of aluminum tappet blocks for shovels.

Vulcan makes a hydraulic tappet kit for shovels, but be warned that the included tappet blocks have some mistakes of geometry in the manufacturing, at least in some, that will cause motor damage.

There are Chinese mfg. hydraulic tappets out there under several labels including Sifton and Ultima that are the worse sort of JUNK possible, and you definitely want to STAY AWAY!

OK, that's the aftermarket hydraulic tappets available as I understand it, today.

Jim

[JBinNC]

Now, what else is there?

For hydraulic tappets, S&S sells the original Eaton made hydraulic tappet insert for shovels, which is the same one Eaton supplied to HD back when. Crane used to sell this same unit, and S&S acquired the rights to this piece when they bought Crane's motorcycle product line. If you can find new old stock Crane hydraulic tappets, they are good. In both cases, S&S and Crane, they offer the stock style tappet body to go with the hydraulic insert, and they are good pieces.

There are some Japanese made hydraulic tappet inserts as well, sold by Drag Specialties and others, but I cannot comment on the quality as I have little experience of them.

These stock style hydraulic tappet inserts, and even used HD pieces, can perform well with cams of up to .450 lift. One set up that works well is an Andrews A grind with the stock hydraulic tappets. Andrews assured me that even though the A grind is listed as a solid cam, it will work fine, and it does.

Jim

[JBinNC]

Now, if you want trouble free tappets, or you want a big cam (and can't afford VelvaTouch) you have the solid tappets and solid tappet conversions.

The factory shovelhead tappet consists of a tappet body with a drop-in hydraulic unit. So, you can pull the hydraulic unit out and replace with any number of tappet adapters.
The one you will see most often in old motors is the Sifton type with the 1/2" dia. aluminum pushrods, and the large radius pushrod tip. These work, but the large diameter pushrods rub the pushrod tubes, causing them to wiggle and leak. (You can often see the tubes moving when the motor is running.) I personally will not use these because of the potential leak problem. There are some kits with 7/16" dia. pushrods that work better.

Next is the '48 - '52 pan style tappets and tappet adapters which essentially work the same. The adjusting screw is in the tappet, and the pushrods are plain, like an ironhead. These work very well with big cams and high rpm, so you see this style in race motors. The main thing is that the plain pushrods can be very strong (depending on mfg.) so you get a nice stiff pushrod for use with big valve spring loads. S&S sells this style tappet adapter kit, with chromemoly pushrods. They used to sell the pan style tappets but I don't know if they still offer them. Eastern and Jim's do offer the pan style solid tappet assembly, with the Eastern adjusting screw being a little weak.

S&S and Colony also sell a solid tappet adapter that uses the existing stock pushrods, and that is the lowest buck way to convert to solids, but I wouldn't use these with big cams.

S&S also sells a solid tappet adapter and pushrod set that uses an evo style adjustable pushrod, and these are good for hot street motors with moderate cams. Crane used to offer something similar, but the pushrods were so long, you had to pull the cam to install the kit, and FUCK THAT!

Jim

[JBinNC]

OK, now the tappet blocks, and the factory hydraulic tappet bodies, not the hydraulic insert itself:

Almost all shovels you will encounter have tappet blocks and tappet bodies that are WORN OUT!
This causes a lot of problems that people wrongly blame on the HD hydraulic tappet insert, which is actually a very good piece.
The tappet bodies new are .731" dia. They will wear barrel shaped fore and aft (their thrust faces) and any that measure more than .001 wear at top or bottom are BAD.
The tappet block bores also wear bellmouthed fore and aft. If tappet and block clearance exceeds .003, the assembly is WORN OUT, and you can have problems trying to run hydraulic tappets with that much wear. Solids will run happily, but you lose a little duration.
Oversize tappet bodies are available, and the tappet blocks can be reamed and/or honed for oversize, same as fitting an oversize piston.

Jim's and Eastern offer the oversize tappet bodies, and most styles of tappets are offered in oversizes too, for fitting in your existing blocks.

There are new blocks available too. Jim's aluminum blocks, real nice and $$. Japanese made cast iron blocks sold by several distributors are good, probably as good as the original HD pieces.

Jim

[JBinNC]

Those are interesting.. One place I did have wear I could see with the naked eye when pulling the heads off were the valve tips.


Is the EVO oil scheme superior on a shovelhead?

No. You cannot use through the pushrod oiling with stock shovel rocker arms, as the rocker arm has no provision for oiling the bushings from the pushrod cup. If you did an evo conversion and kept the stock rocker arms, you would have to keep the stock oil lines as well.

Jim