Exhaust valve locks touching

[Mike M]

I am assembling a fresh ported head with new MP locks and while installing the new +1mm valves (MP exhaust, SI intake I found my exhaust locks (multi-groove) touch. I haven't been able to find any problems or concerns with this on TM, but one quick google regarding locks that touch is that its a big NO NO.

Even uninstalled, I can take the exhaust locks and put them on the valve and wiggle the valve within the locks as they are touching and not contacting the valve.

I have a spare set of new +1mm exhaust valves from SI, using my new MP locks I can do the same thing... the locks contact and I can wiggle the valve inside.

I thought possibly I had the incorrect locks, as the valves are the same and obviously fit the head I'm using.

Then I go back to my OLD ported head with +1mm valves (unknown brand, with unknown locks) and do the same thing... the locks STILL contact and the valve can be wiggled on the exhaust ones. There appears to be no wear on the locks or valves themselves and I used that cylinder head as is for possibly up to 30,000 KMs... with no wear that gets me thinking there isn't actually a problem? But google tells me otherwise?

Thanks for any advice.

[boost geek]

Are the triple groove locks and valves not designed to rotate? I thought all hipo motor builds now used single groove locks on all the valves.

[Mike M]

That makes sense. As explains why I my old head has no wear on the loose multi-grooves after that amount of mileage. Continuing to google on it, but I bet you're right...

Edit. Further googling says this is true, designed to allow the valve to rotate. Done and done. Makes me happy... it was baffling me, I don't assemble enough cylinder heads it seems, but now I know!

Thanks!

[bakes]

Don't run the motor with the locks touching it is the cause that took out my last motor!!!!!!! The locks machined there way right up the valve stem so much that the retainer hit the followers / the valves floated so much that they pounded out the valve seat and wore the new guides out / the knocking sound was so much Cell blink was pulling timing all the time. They only bright spot was the PO gave up and trying to nail the noise down and sold me the car for cheap.

[Warren Stramer]

Do not run those locks touching!!!!!!!!! I always rub them on a sheet of 400 grit sand paper till they have some clearance between the locks and they capture the valve stem tight when assembled.
Do not worry about the valves rotating, they will surely rotate anyway from the motion of the spring winding and unwinding as it is compressed and released during normal running. You could not keep them from rotating if you wanted.

[Shadow]

X3, wether or not Chrysler intended this (because they're all like that) you do Not want to leave it that way in a performance application.

[Mike M]

Well thats nuts... thanks for the tips, was going to let it slide.

Extra stupid considering they are MP valves and MP locks... yay performance.

<goes to buy 400 grit>

[crusty shadow]

even better- ditch the multi groove valves, valve rotators suck in most performance applications.