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Wed Mar 17, 2021 7:28 pm

Hi All, I can't seem to find the answer i'm after, unless i'm not looking on here hard enough. I have some new stainless steel valves in my spares and the rest of the valvetrain is all stock for my 1776 single port that i'm about to start assembling soon. Will the stainless steel valves work okay with everything else stock or should I source stock replacement valves and which supplier sells good quality valves if so? Thanks in advance!

Wed Mar 17, 2021 8:06 pm

Check if a magnet sticks to the tips. If so, you can install and use the same as stock. You obviously need a valve job. They don't just work if you put them in. The valve locks should be ground so the ends cannot touch. With the steel, it was fine, but for ss, it may not be.

Wed Mar 17, 2021 8:24 pm

And remember that SS valve heads can mushroom over time. That's why they say to use lash caps.

As far as valve functionality... As long as they lap well to the seats and you account for them being softer than "regular" valves, you're fine.

Thu Mar 18, 2021 7:14 am

Stainless valves drop in, no issue.

As far as them being soft and needing lash caps is not really true anymore.

Maybe in the old days, but modern stainless valves are just as hard as regular steel valves.

Thu Mar 18, 2021 7:19 am

Ohio Tom wrote: Stainless valves drop in, no issue.

As far as them being soft and needing lash caps is not really true anymore.

Maybe in the old days, but modern stainless valves are just as hard as regular steel valves.

I'd heard that too, but still see sellers saying they require the lash caps.

Thu Mar 18, 2021 7:21 am

Ohio Tom wrote: Stainless valves drop in, no issue.

As far as them being soft and needing lash caps is not really true anymore.

Maybe in the old days, but modern stainless valves are just as hard as regular steel valves.

Yes, this is 100% correct.

Thu Mar 18, 2021 7:22 am

DurocShark wrote: Ohio Tom wrote: Stainless valves drop in, no issue.

As far as them being soft and needing lash caps is not really true anymore.

Maybe in the old days, but modern stainless valves are just as hard as regular steel valves.

I'd heard that too, but still see sellers saying they require the lash caps.

They are only needed on the cheap stainless steel valves that don't have hardened tips; so if the seller says they are required, I would advise against buying them.

Thu Mar 18, 2021 7:26 am

Gotcha, thanks!

Thu Mar 18, 2021 11:25 am

DurocShark,

Roy beat me to the punch, but I was just about to post essentially the same info that he did re the SS valves.

I just ordered a set of his "new" MOFOCO 042 heads and he has assured me that HIS SS valves DO NOT require lash caps!!

I have a set of his "old" MOFOCO 042 heads that the PO had installed, and the valve stems look like new.

Just in case anyone wonders or cares why I ordered the "new" heads when I already have the same size "old" ones, it is because this is essentially a totally new build (case, carbs, cam, crank, P&Cs, etc.) and I want the increased flow and cooling. Roy has been SUPER helpful in helping me with many aspects of the build.

GOOD LUCK and STAY WELL!! 8) 8)

Tom

Thu Mar 18, 2021 12:15 pm

Just to let you know (and others) Manley supplies two different (same size) stainless for the VW. First is a cheaper model, Asian made. Second is a more costly version, made in the USA. When you order their valves you WILL get the Asian variant if you dont ask for the USA made version....and be prepared to wait.

Fri Mar 19, 2021 1:36 pm

I ran the cheaper stainless valves from somewhere random without lash caps bought around 2017 I think.

And the ends of the stems of those valves mushroomed out so you had to file them down to get them through the valve guides.

You could see pitting and a depression in the tip of the valve, the metal was about as hard as the rocker adjuster screw.

After about 50k miles, one of them decided to leave its head in the cylinder, and break up the piston, so the conrod poked through the case top..

At the time I had a complete set of standard valves ready in my spares box to go in that engine.

Now I have a nice shiny new engine from JK ...

Sun Mar 21, 2021 11:03 am

Low quality SS valves are extremely soft on the tails. I will rather run used stock valves than unknown 'SS' from China.

also - I am not a fan of grinding the keepers anymore. I tried them long ago in the 80's and found a valve-to-seat wear that I did not like. t/his was on some small race engines. Grinding the keepers will lock the retainers to the keepers and hence the valve tails too. This in essence did not make the valve rotate and practically stayed in one spot and wear in an uneven pattern. I don't recommend it from my experience w/ it.

If it is street engine, I will rather use the stock configuration and have the valves rotate and wear-in as usual. The valves have to hit the seats on close so the parts can cool - this is what I was taught in school. If the parts cannot cool and overheat, then they come loose or break.

Just FYI - use the info as you like.

Mon Mar 22, 2021 6:49 am

nsracing wrote: Low quality SS valves are extremely soft on the tails. I will rather run used stock valves than unknown 'SS' from China.

also - I am not a fan of grinding the keepers anymore. I tried them long ago in the 80's and found a valve-to-seat wear that I did not like. t/his was on some small race engines. Grinding the keepers will lock the retainers to the keepers and hence the valve tails too. This in essence did not make the valve rotate and practically stayed in one spot and wear in an uneven pattern. I don't recommend it from my experience w/ it.

If it is street engine, I will rather use the stock configuration and have the valves rotate and wear-in as usual. The valves have to hit the seats on close so the parts can cool - this is what I was taught in school. If the parts cannot cool and overheat, then they come loose or break.

Just FYI - use the info as you like.

I do the same. Everyone tells me to grind the keepers, but in my experiance it hasn’t been necessary with good stainless valves and stock to mild cams. I have never used a cam with an aggressive ramp like a Web 494, but from everything I have experienced, the stock configuration works well. Never had an issue with the keeper grooves wearing. I can see this being an issue with poor quality stainless valves with soft stems, or cams with aggressive ramps / valve acceleration, but beyond that, I will likely always allow the valves to float in the keepers.

Mon Mar 22, 2021 8:53 am

Vanapplebomb wrote: nsracing wrote: Low quality SS valves are extremely soft on the tails. I will rather run used stock valves than unknown 'SS' from China.

also - I am not a fan of grinding the keepers anymore. I tried them long ago in the 80's and found a valve-to-seat wear that I did not like. t/his was on some small race engines. Grinding the keepers will lock the retainers to the keepers and hence the valve tails too. This in essence did not make the valve rotate and practically stayed in one spot and wear in an uneven pattern. I don't recommend it from my experience w/ it.

If it is street engine, I will rather use the stock configuration and have the valves rotate and wear-in as usual. The valves have to hit the seats on close so the parts can cool - this is what I was taught in school. If the parts cannot cool and overheat, then they come loose or break.

Just FYI - use the info as you like.

I do the same. Everyone tells me to grind the keepers, but in my experiance it hasn’t been necessary with good stainless valves and stock to mild cams. I have never used a cam with an aggressive ramp like a Web 494, but from everything I have experienced, the stock configuration works well. Never had an issue with the keeper grooves wearing. I can see this being an issue with poor quality stainless valves with soft stems, or cams with aggressive ramps / valve acceleration, but beyond that, I will likely always allow the valves to float in the keepers.

Right on gentleman!!!

This is how we have been manufacturing cylinder heads for 30+ years(and rebuilding them before that)

Race only heads get the keepers ground so they lock in place and street heads get keepers and valves that rotate.

Mon Mar 22, 2021 10:59 am

THe problem we have in these threads is we got people here who will spew out some combo they have never tried and pass it as gospel.

So we got all the newbies all confused w/ all the stupid ideas rolling around in their heads.

But... you make your own bed here. Lie in it. :lol:

Mon Mar 22, 2021 12:57 pm

Re: grinding keepers.

They key to let the valve rotate is to use at least one spring shim so that the whole assembly can rotate. Using the shim to keep the spring from digging in and preventing rotation.

CB single groove valve/keeper/retainers grab the valve tight. Lots of folks have them on their street motors.

If you buy a new set of CB heads, they will come with at least one spring shim.....

This works in my experience.
Street, race, whatever.

Mon Mar 22, 2021 1:14 pm

Ohio Tom wrote: Re: grinding keepers.

They key to let the valve rotate is to use at least one spring shim so that the whole assembly can rotate. Using the shim to keep the spring from digging in and preventing rotation.

CB single groove valve/keeper/retainers grab the valve tight. Lots of folks have them on their street motors.

If you buy a new set of CB heads, they will come with at least one spring shim.....

This works in my experience.
Street, race, whatever.

You are the first person I have ever seen that explained it that way and it makes perfect sense. I would agree 100% that it works.

Ok cool, I learned my one thing today so now I can turn my brain off :?

Mon Mar 22, 2021 3:13 pm

With bottom spring shims, sure it will rotate but ever so slow. It will still eat a pattern in the seat and valve.

For a race engine that will be torn down a lot sooner may be doable. But for street engines with expected lots of miles, HELL NO!

Like I said, people can try it out and make up their own minds.

As designed, the valvetrain in the VW is pretty good. You just have to use the proper parts. I have seen pull-thrus w/ the tail of the valve still in the locked keepers after it broke off.

Lesson: do NOT use cheap ass valves.

Manleys are about as best you can get. I have used the BErg Italians before and seemed okay in street. But I rather have the Manleys.

Or I will just use factory used ones. Plenty of good ones if you want to dig for them.

The original 40mm intakes in 041 heads are also good. I collect them for later use.