Aluminum L20 valve retainers

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spyder
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Aluminum L20 valve retainers

Post by spyder »

Years ago I installed L20 valve retainers on my U20 head which allowed for taller lash pads needed for a reground cam. What I did not realize that they were made out of aluminum. I am installing a different cam and as I removed the current cam I found this! No wonder it was not pulling as hard as it used to.
:shock:
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Anybody know if there are titanium L20 keepers out there?
Last edited by spyder on Wed May 24, 2023 12:34 am, edited 1 time in total.
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Re: Aluminum L20 valve retainers

Post by david premo »

Those are junk, that someone had made. I purchased a set in 2004 and they went oval where the lash pad sits. They are U20 aluminum retainers that use L series lash pads. I bought a set of chromoly ones from Schneider Racing Cams ones and have never looked back. I talked to the person whom had them made about the issue and the reply was he wasn’t very fond of the aluminum either and that they hadn’t work that well. I don’t know how many were made and sold but they were a problem for me. Unfortunately Schneider doesn’t have them anymore, however Stan has something he’s been making for years and I have used them without problems on at least two or three engines so far.
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Re: Aluminum L20 valve retainers

Post by spyder »

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Re: Aluminum L20 valve retainers

Post by david premo »

I don’t think those are going to work if you are using the U20 valve. The stem and keepers are bigger on the U20 valves than the L series valves so I doubt that they will work.
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Re: Aluminum L20 valve retainers

Post by JT68 »

Dave is correct, L-series stuff doesn't work with u20 valves.

Even if they did, you would need to have a shop set up the installed height because ALL the L-series retainer installed heights are different from the U20 height. If you don't get that right, your spring pressures will be totally wrong and you will have another ugly set of problems.

Aluminum retainers were always a very poor choice for a street car and they have very limited life in race engines (a few races then throw them away)-Lucky you didn't eat a valve.

I think we have a set of Schneider U20 retainers that use L-series lash pads and U20 valves in stock, but as I recall the caveat with those is they don't fit U20 springs and require Schneider springs. We have a set of those too if you need them. I don't recall what installed height the Schneider's are, so you'd need to check that, but they are properly hardened steel, so they won't fail like the AL junk that was sold to you.

Since we will probably make more very high performance u20 valve train parts this year, the Schneiders are available as a set. pm or email etc if you would like them.
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Re: Aluminum L20 valve retainers

Post by spyder »

Thanks for all the replies. The reason I pulled the cam is I am going to replace it with the stock "A" cam and use the original keepers with a new Isky 7005 spring set. This car is going to my son and I am removing the go fast parts so it will last. Next task is to replace the 4.88 posi for the standard 3.70 with a posi. The aluminum oil pan is next. I don't know if I will replace the Solexs, Ill see if I can make them work. As I recall back in the '90s they didn't like the "A" cam. He never drove like me!
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Re: Aluminum L20 valve retainers

Post by JT68 »

The 7005 set is not a good choice. WAY to high pressure/rate/installed height. (Much higher than the Schneider which are already high) 7005s will just kill the cam&rockers. Suggest you go back to 68-70 stock U springs if using the A cam- the 7005’s are like 130pounds at 1.7” if I recall, that’s insane for u20.
Last edited by JT68 on Mon May 08, 2023 10:31 pm, edited 1 time in total.
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Re: Aluminum L20 valve retainers

Post by Gregs672000 »

So Spyder, a new car for you or? If you decide the 50 Mikuni are not going to work, I have a very nice set of 45mm/37mm choked Dellortos with filters, stacks, jets and literature that will work well, especially with a B cam if you decide to go that route over the A. I know you know Mikuni well. It may be difficult to get a good result with the 50s and an A...

I hope you continue to run a car. I've always appreciated your knowledge and experience.
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Re: Aluminum L20 valve retainers

Post by spyder »

I got U.F.O.* so I am giving the it to my son. He wants to daily drive it so I need to make street-able. If the 50PPH carbs don't give acceptable driveability, I have the original SU's that it came with. I had those sorted before I put on the solexs.

*ugly, fat & old!
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Re: Aluminum L20 valve retainers

Post by david premo »

Leave the cam, the SU’s work great with all kinds of different cams. I know lots of people running B cams and one guy with a C cam with SU’s. BRE ran a cam with over 600 lift with SU’s back in the day.
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Re: Aluminum L20 valve retainers

Post by Gregs672000 »

Well I'm sorry to hear you're retiring your Roadster commission, however I'm glad it remains in the family!
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Re: Aluminum L20 valve retainers

Post by spyder »

Bye Bye 4.88, hello 3.70...........

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Re: Aluminum L20 valve retainers

Post by theunz »

Now that you’ve made your sons car fast instead of quick maybe you should install a rev limiter so you can slow him down in both areas! Of course being young he’ll still figure out a way to get in trouble😎
P.S. Do the 3.70’s get a limited slip too?
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Re: Aluminum L20 valve retainers

Post by spyder »

Yes to both, the ignition has a knob for the rev limiter and the 3.70 is a posi.
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Re: Aluminum L20 valve retainers

Post by Datsunparts.comInc »

I had a few of those sets and discontinued selling them just about 20 years ago as they are definitely not good. After that and early on, the Chromoly ones we sold were purchased from Snyder Cams when Jerry made them specifically for the U20. After those sold out, Mark Degroff made replica Snyder U20 retainer blanks for me out of Chromoly and machined and adjusted them dimensionally for use with different springs. We had them for the stock springs and a set from Associated. I'm actually thinking about asking Mark to make them again as we received a lot of good feedback and we were not using a modified U20 retainer.

Dean
Last edited by Datsunparts.comInc on Tue May 23, 2023 12:55 pm, edited 2 times in total.
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