Help with heads set up

Hooley · April 15, 2008, 11:32:29 PM

I'am setting the heads up this year on the Bonneville car. What I am working on is the spring pressures. The valves have been ground and the valve stems are set at the same hight. The springs need to be shimmed to get the pressures that are needed. QUESTION: Is there a problem with the bottom of the spring being above the spring pocket in the head???
With shims under springs and above the spring pocket there is a little room for side movement. IS this normal or is this a problem??

Hooley

wayne petty · April 16, 2008, 01:35:27 AM

i take it that the engine will see flat out speeds...

i previously have had to use offset retainers and offset keepers to get the valve spring pressures close... that way no or very limited shims were needed to bring it up....

i have also seen spring shims that had a flange around the outside to retain the spring at its proper angle... this prevents side loading to the spring... not a good thing.... for the spring or the valve stem

i also try not to bottom out the springs when installing them or in the spring tester... carefull ajustment of the spring compressor will allow just enough room to work the keepers in without putting every spring into coil bind throwing every thing off...

i even came up with a design that locks the keepers into the retainer so they cannot come out ... even with a spring compressor...

are you going to use beehive springs??? so there is less chance of a harmonic failure to the springs?

Hooley · April 16, 2008, 07:43:43 AM

Wayne, Thanks for the information. I tried a -.050 keeper but it left the stem in the retainer.

The springs are .550 dia , we're looking for a 230# seat pressure. I am wondering if a new set of valves would be the correct fix?

Hooley

enjenjo · April 16, 2008, 09:57:53 AM

I have done it on street motors with no problems, but I don't have the confidence to say go ahead and do it on a race car.

wayne petty · April 16, 2008, 11:39:51 AM

how much did you take off the valve face?

? or are you thinking of a differnt legnth valve...

?/

how much did you take off the valve seat?

?

just how much do you need to make the pressure you want

do you have a spring pressure tester

you must...

rimac or one of those you clamp in the vice or under a drill press quill...

check out goodson.com for engine rebuilding tools... they only seem to have the normal shims listed... i cannot think of who sells the spring cups... isky, comp , crane, but i have seen them... i dont even see my paw catalog right now... i know that this is not much help...

Jbird · April 16, 2008, 12:57:46 PM

Have you considered using different springs? Another thought would be a "spring locater", maybe you could lathe out a bunch of alooneyum barrels that would press snugly over the valve guide and slip loosely inside the valve spring. Just a couple of thoughts. Strange things happen at 8000 rpm Jbird

Hooley · April 16, 2008, 05:34:59 PM

Wayne, I am not sure just how much was taken off the valve.

I have a spring pressure tester.

The seat pressure should be around 225#

It is a roller ,solid lifter cam.

Jbird, These are new springs and were pricie.

There is a spring locator under the spring. I found out it holds the spring
on the inside of the spring. I am thinking about shimming under the lockator to get the right spring pressure and keep the spring in the right location. Does this sound like a good plan?

Hooley[/quote]

kb426 · April 16, 2008, 06:25:29 PM

I had a set of spring cups to fix what you are describing. They weren't very thick and the center id matched the od of the valve guide. You're delving into valve train harmonics. Even on a drag car, those harmonics destroy a set of springs in seconds. On a car that will run for miles wfo, that could be scarey. You have several options, shorter retainers, the spring cups with shims underneath, and last choice, shorter valves. The last choice would be my last pick. If you're geometry is correct, shorted valves will wreck this and make you loose gross valve lift, cause excessive valve guide wear and god know's what else. If you have custom made valves with the same stem length but a lower keeper groove, you could avoid this. My exp. has been that most racing engines fail because of valve train failure. Because of that fact and the fact that you are at the flats, I'd take no chances.
PS. The spring cups I bought years ago came from Manley
Your spring locators are the reverse of cups. I'd use them.

Fast.Fords · April 16, 2008, 07:51:16 PM

I don't have a solution, but i sure do want to thank everyone for the tech advice.... fighting the same battle on some BBC heads now!!!!

Jbird · April 16, 2008, 08:59:46 PM

I agree with kb426. I'd just make sure the shims can't wiggle around. I'd probably make my own or modify an existing shim to fit the pocket in the head nice and tight. Jbird

wayne petty · April 19, 2008, 04:45:05 PM

here is the manley valve gear section...

http://www.manleyperformance.com/dl/2008/cylinder_head_components.pdf

pages 28 and 29 have the spring cups... out of the 30 pages...

here is the link to the rest of the sections...

http://www.manleyperformance.com/master_catalog.shtml

the spring seats seem to be .062 at first glance... so you might still want to out shims under the seats,....

as for the -050 keepers... those are the wrong way to go. right idea wrong direction.. they took your seat pressure looser..... i did not see +.050 but again i did not look that hard yet...

did the seats get sunk into the heads..

? or too much ground off the valve face?

if you want to post a pic but want to keep chamber design and port design under wraps... use some duct tape to cover the areas as we are only intrested in valve height in the chamber... and maybe a shot down the port through the seat... a well stuffed shop towell into the port will limit the view...

Hooley · April 20, 2008, 07:41:54 PM

Friends, I think I have had an educition on racing heads this last couple of weeks. Wayne ,I have been trying to make this too hard and too persice. A guy that builds BBC racing heads came by. He told me every thing you have said. With him looking at them he showed me where I was over concerned. I will assemble them this week. I feel confedinent with what I am doing now. Thank you'll for your time and help. I'll let you know how they worked.

Thanks agin
Hooley

wayne petty · April 20, 2008, 09:06:59 PM

oh... and one more thing.... for the last 20+ years on things that count... i only use stay lube moly-graphite assembly lube... it the black tube...

this i use on valve stems... and a glob under the valve seals as with todays positive seal valve stem seal there is very little lube leaking in... so after ordnary motor oil or liquid assy lube has leaked out this paste is still there doing its job...

i apply it to the stem and work the stem in and out while twisting till i get a nice even feel to the movement... i also along with a dab under the seal put a dab on the groove to hold the keepers in place...

i use it on engine bearings and cam lobes and lifter bottoms also...

it comes in two sizes ... a small squeeze tube like a tube of rtv... and a big honking tube almost a foot tall...

and when you ask for it at the parts store... if the guy asks what kind of car its for ... deck him..... other brands are not the same... isky lube is as close as i have ever found... and i have not tryed that in a long long time... they may have changed the formula...

good luck with the heads... glad you got some eyes on help....

do you know about hylomar??? for the head gaskets... even though they tell you not too?

??

Hooley · April 20, 2008, 10:47:04 PM

I am glad to know about the Stay Lube. It sure helps to know what does work. I have seen the Hylomar but have yet tried any. I just hate these new gen parts guys. "What year does it fit ,right" Our local parts guy is still old school and knowes the parts and we still carry the old part in ,in a red rag. Thanks again

Hooley

wayne petty · April 20, 2008, 10:59:09 PM

hylomar... smear some on the head gaskets... use fingers... bondo spreader, inking roller.. if it is squeeze tube drop the gasket on... and the head..

if it is spray on... let it air out for 15 to 30 minutes... it will never ever dry... the airing out is to let the solvents in the spray can evaporate..

since i have been using hylomar i have only had one head gasket comeback... and that needed the block to be decked..

on one 4th gen aluminium head motor to 3 gen camaro valve job after the head gaskets blew the cooling fans quit... the customer drove it back steaming like a steam engine... and still it did not blow the head gaskets...

goodson has it also... good up too 600F...multi layer steel headgaskets need it... so much better than anything else out there... i bet lear pilot knows about it...