Found .020 longer valves (OAL) in my head?

[kevinm]

I have a hydro head and decided to take a look at it before i mated it with a minty fresh block.  I noticed the usual valve play in the "wobble" test (seals should be good enough)... then decided to measure the overall length of the valve and found it to be 3.760 (Bentley states 3.740) and also noticed they do not have the vw/audi symbol on them either.  So doing the mesurement as per the Bently regarding valve seats...I fount the one longer valve measured 1.465 from the top of valve stem to gasket surface.  The stock valve, found in an old pile o' parts measured 1.445.  Diff. of .020. Now if you minus the 1.409(Intake value, Dimensions for calc valve seat removal) from either of my valves your still in the ballpark.  Now my question is... Can the cam follower accomodate these differences and why did the last guy that touched this head use longer valves...

Thanks,

[vanagonturbo]

perhaps your measuring device is out of calibration?

[kevinm]

no the valves are def. .020 longer.. the stem dia is bang on, as id the head dia.  All i can think of is these hydro lifters must have lots of forgiveness. 

[Mark(The Miser)UK]

no the valves are def. .020 longer.. the stem dia is bang on, as id the head dia.  All i can think of is these hydro lifters must have lots of forgiveness.  

According to 'KATE' The exhaust valve is 95.6mm or 3.764inches  and the inlet is 95mm. or 3.740 inches I make that 24 thou. So is that your extra 20 thou?

[kevinm]

I think my Bentley says that the intake and exhaust vale are the same length... All my valves are the same lenght in this head... and .020 longer than old oem ones i have sitting around...

[Mark(The Miser)UK]

I think my Bentley says that the intake and exhaust vale are the same length... All my valves are the same lenght in this head... and .020 longer than old oem ones i have sitting around...

Nope, as I said for 1.6 diesel valves, unless pre 1986 ie non hydraulic, in which case inlet valves are 104.8mm and exhaust are 104.6mm.

Having sold my wife to pay for the p & p for a Quantum Bentley, I can safely say that it is not the bible, and is full of mistakes.
There is a lack of info other than an advert for unobtainable tools, unless you want to rebuild a gearbox, or look at an electric circuit.

I also have some of the VAG mags,which are the main source for the Bentley and from what I've seen of the updates, VAG were on the same learning curve as the rest of us

[kevinm]

Ok, I just checked every single valve in my other crap head which has oem valves in it and they all measured the same 3.740 +.002-.000... Ive even measured these valves when they are seated and from the valve cover surface down to the tip of the valve they are in fact .020 shorter than these non oem valves i have in this "working" head im trying to rebuild...

[Mark(The Miser)UK]

Ok, I just checked every single valve in my other crap head which has oem valves in it and they all measured the same 3.740 +.002-.000... Ive even measured these valves when they are seated and from the valve cover surface down to the tip of the valve they are in fact .020 shorter than these non oem valves i have in this "working" head im trying to rebuild...

It would appear thst both my Bentley and VAG, are for mech heads and so no help, other thsn they tie up with the EKTA.
According to EKTA 3.74 is the length of inlet valves only.

Exhaust are 3.764 inches.
Therefore your test head has valves that have been shortened, or they are all inlets.
Otherwise EKTA is wrong.
Perhaps someone else can add more info as it is a bit of a mystery

[kevinm]

anyone? can i run these longer ones?

[erice1984]

There is a mix on Rockauto.com

8mm AAZ valves
  Exhaust Valves  -  95.1 and 95.0
  Intake Valves  -  95.0

7mm AAZ
  Exhaust  -  95.6
  Intake  -  95.5

[erice1984]

anyone? can i run these longer ones?

The first question I have is,  The keeper grooves .020 further away from the head of the valve?  if so then I don't think they would work.

If the grooves are the same distance (which I am betting they are) then check the clearance that you have from the upper spring seat to the top of the valve stem to see if the stem breaks the top of the spring seat plane.  Understand?  If it is below or did not break the spring seat plane, then I think you should be fine because the stem will not contact the lifter and all will be okay.

[Mark(The Miser)UK]

Are you saying that your old OEM valves are all the same length? That isn't correct either

The exhaust valves should be the same length as your new ones.

Perhaps new ones are made to the same length for production cost reasons.

Are the valve heads thicker on the new ones?

More input please everyone