installed height valve and spring

[JonC]

I know this has been beat to death, I'm nervous about doing it wrong. The basics are 48 block decked but not enough to hit the seat areas, seats ground, chevy (manley) valves seem longer than .060, but I haven't measured them yet. New guides, replacement ford retainers. I am running an L-100 cam just got it back, and was going to use isky springs and adj. lifters.

I borrowed Old Rons method of installing a guide and clip making sure it was pushed up hard to the block had a new valve and retainers and locks in place no spring. took a bolt that was two inches long and placed a nut on it adjusted the nut to lengthen the spacer till it just slid in between the guide where the spring sits and the retainer. measured it and got 2 & 1/4 inches exactly., seems long to me. I have read several times on this forum about a 2 inch installed height, have I missed something.
At two and a quarter I am thinking I may be able to use the stock lifters.

[Ronnie]

Installed height has nothing to do with valve lash settings.The length of the valve determines where you start for lash.The installed height is how the correct valve spring pressure is arrived at for seat pressure when the valve is closed on the seat.50 to 65 lbs as an example.This height is achieved by installing vsi shims and or compensated valve locks or both to get correct height but you must then check the spring tension at that height to confirm seat pressure.You need to test the springs at 2 1/8" or 2" or 2 1/16" etc to see what they come in at.Test springs and shim to that height.
Are you sure of the 2 1/4"
R

[JonC]

I know the installed height is not important for valve lash I was doing this so I can determine the spring pressue as you suggested, what worries me is the 2 1/4 length seems long I will check it again but i already did twice.

[GOSFAST]

Hi Jon, you could be that "tall" with the longer valves?

I have a similar build here with the factory replacement Manley valves (A713) and have a height of 2.170". It will end up with the correct shims at 2.100" and yield 65# with the Isky #185-G's.

The A-713 Manley's have the keeper grooves down .260". This dimension is somewhat critical when chasing installed spring heights!

If the lifters "sit" deeper (from a reground cam) you "benefit" from the longer valve stem, BUT, the drawback is the keeper grooves are also "higher" up on the longer stem! This becomes an issue!

You're limited with the number of shims you can "stack" to get the correct installed height!

The A-713's are 4.820" long.

(Add) To make clear(er) what I'm saying about the (+.100" nominal) valves is this: it would be ideal to have the keepers "moved" back down to the "stock" location on the longer valves. The keeper grooves would/should end up at .360" (nominal) down to maintain the correct relation to the installed height! Lash caps would be another option with the "stock" valve lengths.

(Add) I put a photo here to show what is sometimes needed. That "lowered" groove is down .400". This would help with the spring height.

Thanks, Gary in N.Y.

P.S. If possible post the Manley valve number you are using??

[JonC]

Gary the Manley valves are part number 10077-8 1.5 dia. i installed the cam (L100) and used the stock lifter and have .006 clearance not enough per the spec of .016. I was concerned the adj. lifter would not go short enough but it does so I guess I am all right. I double checked theinstalled height and keep coming up with 2.250 so i will check the spring pressure on the issy single springs at that dimension to determine if and how many shims I need. I wish I had a valve tip grinder so i could use the stock lifters they are so much lighter than the new solid adj. lifteres but it's what I have. Thanks for the input, Jon

[flatjack9]

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2.25 does not seem odd to me. I think you are on the right track.

[GOSFAST]

Originally Posted by JonC

Gary the Manley valves are part number 10077-8 1.5 dia. i installed the cam (L100) and used the stock lifter and have .006 clearance not enough per the spec of .016. I was concerned the adj. lifter would not go short enough but it does so I guess I am all right. I double checked theinstalled height and keep coming up with 2.250 so i will check the spring pressure on the issy single springs at that dimension to determine if and how many shims I need. I wish I had a valve tip grinder so i could use the stock lifters they are so much lighter than the new solid adj. lifteres but it's what I have. Thanks for the input, Jon

Hi Jon, the height you have 2.250" will yield 20# with the 185-G springs!

If you are able to "squeeze" a pair of .060" shims below them you will see 45# (2.130"). Still somewhat low for our preference??

Thanks, Gary in N.Y.

P.S. We have at our disposal some "custom" (7*) valve locks that lower the heights by .050". Not sure how much this will help, but the locks are fairly expensive, they are "billet" pieces! Also not sure whose retainers you are using, "stock" or aftermarket??

[JonC]

Gary, I am off to the speed shop Friday to get shims and values for the spring rate. I am not aware of a problem stacking shims to get the 60 pounds I need, I should be able to go two up top and one at the bottom, but I haven't looked at the bottom of the guide to see how much material is there. If I have to I guess I can get different valves, so it would appear small block chevy valves are not the same. figures. Thanks for the help.

[JonC]

One other thing I just thought of my manley valves have two sets of grooves, I was told that the upper groove is for a valve seal and indeed the locks fit loose on that groove if I did use that groove my spring pressure would be much greater, but I would be worried the locks could fall out.

[JonC]

I guess I solved the mystery, if I use the upper groove the locks are tight and the installed height is now 2.010 no shims will be needed but spring pressure may be a little high I will check that on Friday, if required I could machine off the guide to increase height, boy do I feel dumb sometimes, thanks for being my sounding board.

[Karl Wolf]

The grooves on the chev valve stem are for different things... The one close to the tip is for the keepers, the groove closest the the head is for the chev valve stem seal... If you're going to use the seal groove for the keepers, do yourself a favor and compare how the two different grooves fit the keeper, I would magnify to inspect the fit...

Karl

[JonC]

I was afraid of that Karl, I will be at the speed shop on Friday and see if we can sort this out, Thanks for your input. Jon

[Ol' Ron]

I've checked allot of valves and never came up with that height. However, using the Isky sprigs just shim to 50-55 lbs. I doubt very much you'd have have any coil bind.

[Walt Dupont--Me.]

I usually use Seal Power chevy valves on street engines, There cheaper than Manley and last just as long as these million dollar engines, I've used the 2nd. groove for keepers (cain't see any reason not, thay have a flathead surface for the keep to seat on fit fine in the retainer) have also used 2nd groove with short stock 51=53 springs and come up with a decent seat pressure with no shims and no coil bind. There is alot of combernations it just takes years to figure them all out. How many of these engine on this site are running Bonneville? Walt

[Russ/40]

Originally Posted by Karl Wolf

The grooves on the chev valve stem are for different things... The one close to the tip is for the keepers, the groove closest the the head is for the chev valve stem seal... If you're going to use the seal groove for the keepers, do yourself a favor and compare how the two different grooves fit the keeper, I would magnify to inspect the fit...

Karl

Karl, explain for me how a valve seal can function riding up and down with the valve? don't valve seals have to be fixed to the guides?

[Ronnie]

Originally Posted by Russ/40

Karl, explain for me how a valve seal can function riding up and down with the valve? don't valve seals have to be fixed to the guides?

That seal configuration applies to overhead installation in a small block not to a flat motor.That seal prevents oil from rocker from draining past the keepers and down the stem to the guide.

R

[flatjack9]

Originally Posted by flatjack9

2.25 does not seem odd to me. I think you are on the right track.

Yup, I was thinking 2.125. Duh. 2.25 - not good.

[GOSFAST]

Originally Posted by flatjack9

Yup, I was thinking 2.125. Duh. 2.25 - not good.

Hi Jack, he has that add'l height due to the valves being exactly .100" longer than stock!

The Manley 10077's are 4.920 exactly, the Manley A-713 (replacements) are 4.820. If he had the shorter valves he would be at 2.125", assuming the keeper grooves are in the "standard" .250" (nominal) down!!

Now, the Manleys he's working with help just a little, the grooves are at .290" down, which is .040" (nominal) "tighter" on the installed height.

(Add) If we were building the entire unit here I would just make the valve sizes as needed for the platform! Normally speaking we only use Ferrea's valves anyway when possible!

Thanks, Gary in N.Y.

P.S. Jon, simply give Manley a call (732 905-3366), ask for Jesse, and ask about using the 2nd groove. I would assume them to be identical!

[blown49]

I think the Manleyl ocks are larger than the stock Ford locks as well so that may also compress the spring some more if you use them.

Jim

[JonC]

Thanks for all the information, I am finally figuring all this out, I will call Manley and if I can use the second groove, ther is no problem except maybe 70 pounds of pressure with no shims but I will check that with the spring tester. If I need to I can machine the guides to reduce pressure. Jon