weird valve clearance adjustmet method

Chris Obert

autocrosser, X driver
Folks,
I am working on a client's hot rod big valve that was built by some one else. The builder refuses to answer emails & return phone calls, so I am asking for help from anyone else that might be familiar with the valve adjustment method shown in the picture.

I need 8 new valve buckets, anyone know the original application?

The valve adjustment pucks are made out of soft material that is wearing and is the incorrect outside diameter. Anyone know if these are production anything?

Any identifications appreciated, otherwise I will go on a goose chase for the buckets & have hardened pucks made in the required thickness.

Thanks,
Chris Obert
 
Here is a picture of the valve setup....

That Chris is asking about.
valvesetup.jpg

It is very different than anything I have ever seen.

Ciao,
 
So Chris... are you saying these "pucks" fit over the...

... valve end and spring and the cam rides on top... with nos shims or other adjustments that I can see.

Shims placed inside the cups would help with clearance issues but not deal with the overall "softness" of the puck, huh.

Other than making entirely new pucks... You might consider taking some larger and thicker shim material and machine a slight cup out of it that fits over this puck... so the new hardened material faces the cam and protects the puck...

The original pucks could also be machined down and then shims placed between the two also... but maybe just making new pucks would be the way to go then.

Otherwise... I have no idea where these came from... hope I gave you some ideas though.
 
Jaguar???

loks an awful lot like the XKE type valve adjustment. It has been a looooong time since I've worked on one, but I remember them looking like that. It could also be an early Lotus twin cam from an Elan or Cortina.

The buckets appear to be too large for Jensen/Lotus 16v engines (esprits and such), is this similar to an Alfa?? Some bikes used shim under buckets as well (early Suzuki 750s for example).

I would surf the web for these engines and maybe take a tappet to a motorcycle dealer (or a european parts dealer if you have one) and compare the parts...

Good luck!
 
Guy Croft

Talk to Guy Croft in the UK. He did a similar setup for me last year when fitting a 300 high lift cam to a head. The spacers to fit on top of the valve stems were definitely a hardened material.

Steve
 
Indeed a peculiarly British solution

Bucket over shim was used on the following British cars:

Lotus-Ford Twin Cam and the 907 Twin Cam _ .060" - .150" in .001 steps.
Cosworth ___________ .060" - .150" in .001 steps.
Coventry Climax ______ .060" - .150" in .001 steps.
Hillman IMP __________ .060" - .150" in .001 steps.
Saab 99 _____________ .090" - .120"
Triumph TR-7, Dolomite etc. _________ .070" - .120" in even sizes (.070, .072, etc.)

The Saab 99 8v used the same engine as the Triumph TR-7.
 
If you want to ask some Jaguar experts, here is a link....

...since I got my XJS, I have been getting my technical advice from Jag-Lovers forum. Not warm and fuzzy like XWeb, but some of these guys really know there stuff!

http://jag-lovers.org/

Click on the "Forums Home" tab and then choose a category.
 
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Looks like Alfa shims and tappets although, as mentioned above, Jags use a similar setup.

The spec on the diameter of the tappet is 34.973 to 34.989 mm (1.3769 to 1.3775 in). The Alfa V6 intake tappet and the 4 cylinder intake and exhaust tappets are the same size. Shims run 1.5-3.5 mm thickness, either 8 or 9 mm diameter.

To adjust the size, people have been known to sand down the shim to adjust it when they didn't have the correct size. I personally think that would damage any hardness treatment given to the shim, but I'm not a machinist. This might explain why they are "soft". You can get the shims wherever Alfa stuff is sold.

They are adjusted the same way a Fiat is except you have to pull the cams to get to the shims. This time consuming, expensive and antiquated design is the one of the reasons the Twin Cam Fiats were such a revolution in engine design in its day. The simplified valve adjustment on the Fiat, along with the timing belt in stead of chain, enabled a relatively cheap car to have a twin cam engine. Before then, only expensive Alfa's and Jags, etc. had them. I believe Fiat patented this method of valve adjustment and other car companies paid royalties to Fiat for use of their shim design.

Hope this helps, best regards, Chris
 
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Price for set is 120e + delivery
Reason is for use is not complicated adjusting but big save if weight or like you have 50% lighter valves .....
yes if you have small knowledge of engines and write dim of shims on top of valves what you need ( if valves is 8mm -alfa /mettelli shims ) for other 7 ,6 or 5,5mm valve steam must is make new on lathe is not complicated like somebody think .Few "big" firm buy from me and sale for + 100% higher on market....
I have OE followers too...
 
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The mystery

Thanks to all for the suggestions & offers of parts. Ends up I was able to get the builder on the phone Friday (he sounded dissapointed when I identified myself), that's what he gets for answering!

He claims all his stuff is his own design. He modifies stock Fiat buckets, and makes the adjustment pucks out of 1/2" rod. He also admits he has had some serious hardness problems, and has promised to send me everything I need in the correct thickness all heat treated with his new process. At this time it seems to be the best option for my budget concerned client... I am concerned about sonme of the other aspects of his set up, but at a certain point you just have to make some assumptions.

If you recognize the set up (from the pictures Mark Plaia posted, thanks) as what you also own, you might want to check into the condition. He admitted that his hardness issues has destroyed a lot of cams.

Chris Obert
 
Sure Looks Like an Awful Lot of Work For ?

It would be an interesting comparison to put the stock FIAT bucket with ~3.5mm shim, spring retainer and keepers on a gram scale and this "modified home brew" to see how much weight savings there really might be.

I got to wonder why all this as the stock FIAT buckets, shims and etc work just fine for most every level engine tune with few if any problems.
 
all that work...

The upper valve cups are 'titanium', so I can feel pretty good saying that there is an overall weight loss. But I don't think the weight saved is worth the trade of partial engine disasembly just to adjust the valves.

Especially when the reason it needs adjustment is because the parts are failing.

Why? It's obvious to me the reason for all of this is so the valves can be adjusted. The difference in valve puck thickness on this engine is larger than the range provided by Fiat.

IMO, it's just a way to cover your ass when not setting the valve stem height to the specification needed for your camshaft choice. From my own race car I know it's not an easy first step.

Chris Obert
 
It would be an interesting comparison to put the stock FIAT bucket with ~3.5mm shim, spring retainer and keepers on a gram scale and this "modified home brew" to see how much weight savings there really might be.

I got to wonder why all this as the stock FIAT buckets, shims and etc work just fine for most every level engine tune with few if any problems.

The stock fiat cam follower (bucket) and ~ 4mm shim weighs in at around 80grams, the alfa/osca style follower is around 48.5grams and the lash caps are around 3.5 to 4grams ... so it's around 28/29grams (more or less an ounce of weight) per valve ... that's a fair % of weight saving... and if you want to build a 9/10k rpm engine (combined with lighter vavle spring retainers, they can make all the difference (valve float becomes a thing of the past)

SteveC
 
Titanium is not a good choice for cam follower material, there is a tendency for it to gall on steel, this could be why the cams are developing problems with this set up.

Indeed, lowering the weight of the valve train improves high RPM ability, but is this engine a real race engine that is run constantly at 8,000+ all the time? If not, is all this really worth the trouble?

It might be worth discussing with customer in question about how the engine is actually used and it going back to the FIAT pad on top bucket might be a wiser choice for the reality of how this engine is used.
 
I knew the Alfa buckets and small shims were lighter, but not 28/29 grams lighter. Indeed they will make a difference valve float at nee 9,000+ RPM. They are also smaller in diameter than the FIAT bucket which makes installing them into the FIAT engine more involved. The smaller diameter could affect how the cam lobe interacts with the Alfa bucket. Regardless, except for the tendency for that Alfa twin cam to drop oil passage plugs on the crank, it's one nice engine in many ways.

Has anyone installed Alfa buckets, shims and spring retainers into this FIAT engine?
 
Oil Issue

I can see the weigth savings, but... from where I sit this installation is not designed on a Fiat engine to get much of an oil bath under the lifter bucket. It is apparent that there is metal to metal contact and wear occuring here. Possibly in other engines there is a method of forcing oil under the bucket to stop the wear problems. It appears that both the bucket and the shim are wearing.

I have worked with titanium and it is drillable unlike the hardened buckets on the Fiat. Possible 2 small holes at the edge on the top would allow enough oil to drip down to the underside of the bucket and shim to prevent the wear.

TonyK.

Grimsby Ontario Canada.
 
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