Help me out here. Working on the subject and can’t figure it out.
9590 cam. 0.426 lift on the card. Adjustable pushrod tool.
I get to 0.426 lift. But the geometry between the swivel foot and the valve is wack. That is shortening the PR.
Stretch out the PR and i get 0.430 lift and almost straight valve to adjuster. The foot is too tight to the 1.7 rocker boss.
Bought some shims to lift the rocker stand and try that.
Question is: why am I so far off the card lift? Does it matter?
When using the swivel foot on the 1.7 rocker arms you have to grind back the bottom of the rocker arm.
Some do it on a milling machine , but you can do it with a grinder. Just be sure to keep it level.
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I do plan on removing material. Is it about 0.060” that needs to come off?
It just seems odd to have a published lift that can’t be used.
I had my rockers milled, but I can't remember how much. I rebuilt this assuming a mild cam. I think I was right around your numbers. I remember needing to shorten the stock PR by a very small amount.
Don't worry about the lift vs the card.
Instead worry about getting the geometry correct.
I take more than .060 off and the countersink must clear the foot in all directions.
I don't use shims, at least not much shim.
I cut the swivel foot down and recut the slot, as the screws can/could hit the valve cover.
The cool trick for doing this is to put two 32T blades in your hacksaw, first cut the slot deeper, then grind off the excess thread.
The counter sink is a nice touch. great picture. Tells the whole story. Not sure I can do that. Might have to take them somewhere.
I measured the boss (isn't that what the threaded part of the arm is called?). I got 0.492 on two, 0.502 on one and 0.496 on the last.
I figured to take the 0.060 from the 0.492 and get 0.432. Then shoot for that on all 4.
So at this point all my lift attempts with the adjustable push rod tool have yielded a lift with in +/- 5% of the card. So I should not worry about the final lift result?
Thanks for the input. Heads are camper specials.
I have removed about 0.060”. There is no way i am gonna be able to counter sink. I tried a shop today. He wanted nothing to do with it. He did try one, but just succeeded in heating up the rocker and was pissed that he may have ruined his tool. I have another to try tomorrow. But that guy succeeded in bending my 1.8 crank 7 years ago. Maybe one other shop to call in Nashville tomorrow.
So 8 rockers don’t weigh that much. Who has a shop i can send them too?
Thanks.
I used this guy and he seemed to do a good job.
https://www.thesamba.com/vw/classifieds/detail.php?id=2130116
My 9550 Cam, .426 lift ended up at 436. Bonus!
Len and i talked about other machine work. IIRC he does not do walk in stuff. Mostly his own head work. I was lucky on my 1911 build in 2012. HAM found a 2nd 1.8 head for me and rebuilt 2 for me. This time i went with new type 4 store camper specials. Built by HAM. I got better service working with LEN the 1st time vs TIV store.
As of right now I ended with IN 0.430 and EX 0.408 both yielded a good 1/2 lift angle. Just a smidge of swivel foot clearance with no counter sink.
With the 9590 you should dial in around a 27.1cm pushrod on the intake, to net .434” lift~
The exhaust side will usually never net more than .410” lift due to the rockers. Typically the pushrod on the exhaust side will run around 27.0Cm in length to net the most lift.
These are examples, but usually pretty close. There’s 11 variables that play into this, the biggest being flycut depth and cylinder shim figures.
I have taken up to .080” off of rockers, then lightened the 35 grams, with no issues. Those were for the 2563cc in my 356C, which has been together since 1999 and I haven’t broken a rocker yet..
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