The Silver Buick's well Silver Buick!

[BBR]

ow ow ow ow

I'd say those valves were more than just touching!

[Russell]

You check your push rods for bends?

[TheSilverBuick]

Push rods are good. Worse valve was out of round by .008" (Nick says max spec would be .00213"). I cleaned the piston tops yesterday and the carbon makes it look worse than without. Most the valves have witness marks all 360* around them, so most were gentle enough to keep rotating.

[TheSilverBuick]

Now for some "Days of Our Lives" drama that is reality TV quality. I ordered up the intake valves from TA Performance and I get a call back about two hours later saying they only have seven They are not standard Buick 455 size, they have thinner stems, and slightly larger valve heads, so I tell them I think I have at least one that is good and send the seven (#8, can't even feel the mark on the piston with my fingernail and my measuring device did not have any deviation on it).

So I drop the heads and valves off this morning at L&R Engines (http://www.lnrengine.com/) in So. Cal. and over the phone they were pretty sure they could have it done in a day, but when I got there one of their "valve" guys called in sick ! Ahh! and they were not sure if they would be able to have it done by end of tomorrow (Friday). They called me up right at closing time and they told me I do in fact have ONE valve that is good *whew* reality TV drama sliding in to home here and they expect it to have it finished tomorrow. They are going to call me around noon tomorrow so I have time to make the ~40+ minute drive out there before they close.

[CDMBill]

How did they address the 'thinner' stems, knurling, new guides?

Be sure to carefully inspect the lifter cups and if you are feeling frisky pull them apart and check for brinneling (sp?) or other damage to the plunger or body and then roll it over and check the cam lobes. I am sure this is my valve train paranoia talking but losing a lifter can be bad.

[BBR]

Bill his aluminum heads are probably set up fro 5/16" valves and stock Buick 455's are probably 11/32 or 3/8".

Randal seriously, if you ever need valves: http://www.sivalves.com/

They have good prices and are nice to talk to on the phone as well.

[TheSilverBuick]

Stock is 3/8, these are 5/16. By thinner, I didn't mean the ones I purchased were thinner than the ones in the head, I meant thinner than stock Buick. Likewise on the valve head diameter.

Cam looks fine to me, and to me it looks like a lifter pump up is when the contact happens.

Thanks James.

[Scott Liggett]

Randal, your cam.hydraulic and very mild by today's standards. So are the valve spring pressures. I wouldnt worry about it. Do give your lifters the once over. If you can disassemble them to inspect the plungers and clips inside.

There nothing more stressful in this hobby than being at the mercy of shops and their socalled word of when they will have your stuff done. I would make them ship your heads on their dime if they dont finish them on time.

[milner351]

Geese o pete's - you were a few thousandths away from disaster - make sure you clay this thing - hopefully you've retained one of your used head gaskets. put the clay - or a wad of tin foil in the piston valve pocket in a few holes, then some oil (so the clay doesn't stick to the valve and pull away) and put a few head bolts in with the used gasket.
roll the engine over a few times and pull it apart again and measure the cross section of clay / tin foil to check the p/v clearance
- I believe the minimum for most set ups is close to .100" for exhaust to give some insurance for valve float.

Changing your cam timing may have made the p/v better, or worse.... ?

[TheSilverBuick]

I backed 2* out of the cam timing and set up #1 today with some clay. I'm going to do one on the passenger side tomorrow as a double check.

The exhaust I measured at .110".


The intake I measured .142".

[milner351]

NICE!

just curious - how "solid" where your hydraulic roller lifters during this test?

I ended up welding a couple old stock lifters solid for checking purposes.

[TheSilverBuick]

I was trying to look up the average adjustment spec on hydraulic lifters, from fully compressed to fully open, but did not find one. Overall I believe I'm light on my lifter pre-load, or at least originally was, but the head has been shaved a bit now, so not exactly sure where it sits (hence why I thought perhaps some valvetrain chatter would quiet up when I assembled it in March). I tried compressing some of the lifter cups with a pushrod in hand (as I was inspecting the rollers and cups) and all of them were pretty dang solid uncompressed, but the valve springs obviously exert much greater force on them than I do. When I do tonights test on #7 (the worse looking valve/piston) I'll take a look down at the lifter cup when the valve is fully open to see if I can quantify the compression.

Unfortunately I have no "spare" buick roller lifters, as I had done the same as you with a stock hydraulic in the past.

[milner351]

Yes - those lifters are likely 3x the price of the stock ford rollers I was dealing with.

Sounds like you have things well in hand as usual.

[BBR]

Dude how far in the hole are those pistons at tdc?!?!

[CDMBill]

typical aftermarket stock pistons tend to be down .040+ from the deck. I run mine .045 down from the head surface with properly crushed head gasket. Quench baby.