i know this topic has been beaten to death but i just can't seem to get it... i have 1.7 rockers on my 2.0 so that i can put swivel foot adjusters in. But, when I put in the swivel, i can't set the clearance correctly, or at all. I'm pretty sure it has something to do with geometry, but as i didn't crack the case, I don't know what type/size cam is in there. I was htinking maybe push rod length is off - what should it be? I'm very frustrated knowing vaguely what is wrong, but not sure how to check it or fix it....I'm thinking I'm just SOL and should put the standard adjusters back in

1) were the rockers decked .060" on the face?
2) yes, you will require cut to length pushrods to get the geometry right
3) you will most likely have to buy shims to shimthe rocker assemblies out.

you want the adjuster parrallel to the valve stem at HALF lift...

for some reason i thought that was only if it was modified. guess i'll stick with the stock stuff for now....
thanks !

Aaron if it is all stock can't she just shim the rockers a bit to make the swivels

adjust? I think it will work.

No. Shimming is bad for 2 reasons --

1) it moves the adjuster's contact point on the valve stem face up (as they are oriented in the car). Instead of contacting evenly from one edge to the other, putting even side load on the valve stem, it rolls higher up, putting more load on the upper part of the valve stem face, and less on the lower part.

2) Simply shimming the rockers without changing pushrods would change starting angle of the adjuster. Normally, to get the adjuster parallel at half lift, the angle would be (for example) -15 degreess at zero lift, and ending at +15 degrees at full lift. Just shimming would move the zero-lift angle to (I'm guessing again) -20 degrees and the ending angle to +10.

Then again, swivel feet adjusters shouldn't put as much radial load on the valve stem as plain adjusters, so precise-ity shouldn't matter as much.

thanks guys for the explainations & input - makes much more sense now.

i agree that i want to do it precisely, or not at all. otherwiswe, probably causes more problems than its worth. guess its that type-a personality trait. so for now i think i will just use stock and when i win the lottery -ha- i will go back and do it correctly.

I don't understand, why would the pushrods need to be cut if you decked the rocker faces .060"? From what I understand, decking the rocker face allows you to thread the new adjuster far enough into the rocker such that the face of the new adjuster sits where the face of the old adjuster sat. Without decking the rocker, you would never get the new adjuster in far enough, and would have to shim in order to get any adjustment. Anyway, if the new adjuster face is where the old adjuster face was, and nothing else has changed, then why would the geometry have to be changed??

I agree, if the surface of the adjuster that contacts the valve stem ends up in the same place, there shouldn't be any need for new pushrods and valve train geometry.

.060 seems to be written in stone but does anyone know why you coldm't go .080 and gain a little more adjustment.

Dave

I think .060" is how much you need to go to get the new adjuster face back to the stock location. The only reason why I think you would need to go farther is if your geometry was goofy from the start. I wouldn't want to go much further anyway, I think the rocker starts looking a little thin at .060" reduction.

-Chris

to get enough positive and negative adjustment on the adjuster AND give it room to swivel... you need to either shim the rocker stands, or go with shorter pushrods, OR both....

for me... i had to do both... to get it dead nuts exact at half lift...

and i have a few turns of adjustment each direction if i need it....

Hmm, well I wouldn't make the blanket statement that everyone needs to because I certainly did not have to shim the rockers, the feet have room to swivel, and I have adjustment in either direction. I did not have to change the pushrod length either.

Then again, my cam is pretty mild, and my geometry is not dead on. I was always under the impression that the update to 911 adjusters was drop in, excluding the facing of the rockers. Guess I'm wrong . . .

I have a radical cam.... and my geometry is SPOT ON....

i got it pretty dang close with no shims but to get perfect i used .060" shims...

I have a 9,000 word article on rocker geometry on my forums- read it as it utilizes the 911 swivel foot adjusters as it's base.

All "Swivel feet" adjusters are not the same- if they are not genuine 911 units you may as well throw them away.