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Checked with Len and he said I am good with the .520 lift on his heads. Wants me to verify minimum of .030 total clearance between the coils of the springs which I will do.
Checked intake valve clearance from piston with play dough and I have .126 so that is good.
Next step is to measure my adjustable pushrod (12” caliper on way from Amazon) then “rinse & repeat” for seven more.

Thanks for the help everyone.

Brook

Bsherrard wrote: ↑Sat Jan 04, 2020 9:49 am Clatter
When you say thinner shims under the springs - am I correct that this would give more clearance to bind allowing for more lift than the original limitation of the head design?
Brook

Correct.
Thinner shims give more room,
Thicker give less.

Measure actual lift at the valve.
With so much variation, you'll want the real measurement; Not theoretical.

Clatter
Absolutely! I am measuring each valve separately to get the correct lift and pushrod length.
Thanks
Brook

OK - so I finally completed setting up my valvetrain geometry. I had to order an extension for my dial indicator to allow me to get better alignment with the valves and better clearance. Also had to get a 12" digital caliper to be able to measure the adjustable pushrod after setting it for each valve. I was able to get all of the intake valves to the same lift and all of the exhaust valves to the same lift. The intake valves are all set for 0.520" of maximum lift and the swivel feet adjusters are aligned with the valve stems at half lift. The exhaust valves are all set for 0.481" of maximum lift and the swivel feet adjusters are aligned with the valve stems at half lift. both of these lift measurements are within the +/- 5% of the specified lift for the camshaft but obviously the intake valves are at the high end of that tolerance and the exhaust valves are at the low end of that tolerance.

Are there any concerns with this? Based upon another post where Clatter indicated that exhaust lift is always less than intakes I am thinking not but I guess I am looking for a little confirmation before I got and get all the pushrods cut to length.
thanks All!

Brook.

Sounds to me like you have nailed it . It's a shame the aftermarket rockers BAS sell are so expensive . they have adjusters on both sides of the rocker arm so pushrods don't have to be a critical length .
https://www.ahnendorp.com/VW-Type-4---P ... -1-37.html

Thanks Wreck
Yeah those rocker arms are pretty sweet
Brook

You need to talk to Hoffman about the head setup and springs installed height and cam lift issue, since he built them. Which I SAW YOU DID

But basically you still have two choices, 1. change the cam or 2. change the springs.

If it was me, I would change the springs, I don't like binding issues, it's bad for the cam. So you need to find out the recommended springs for that cam, and a 9500 I believe is a Raby grind.

And one other issue: And this is for anyone who thinks they need a Reduced Base Circle Cam. I've found RBC Cams are needed for 82mm strokes and larger. With the right rod up to 80mm there's enough clearance if the rods are aftermarket with 5/16" bolts but should be checked to be sure, 80mm strokes also have to be checked for clearance if the bolts are 3/8". RBC Cams tend to wear faster than standard base circle cams, so I try to stay away from them as much as possible. Brook I don't know what rods you used, you didn't post that info.

Richard
I am using H-Beam 5.325 Rods w/ type 1 rod journals.
I did have to do a little clearancing of the case and the rods but everything spins freely in mock up now.
Brook

I should of been clearer, my clearances are with the 914 2.0 ltr jrl - 1.967" and a 5.5" or longer rod. Shorter rods with increased rod angle can cause some clearance issue's them selves. And again rod bolt sizes make a difference also, the out side dia. of the big end of the rod increases with a 3/8" bolt causes clearance issues compared to rods with 5/16" bolts.

Type 1 jrl's are 2.165" and the rods big end get proportionally larger due to jrl size, which also reduces rod to cam lobe clearance.

With the jrl size and rods, you had no other choice than going the RBC Cam, which is understandable.