Sup people

I know that if one is changing cams to a bigger set they need to do shims and check valve clearance but

Im changing just my intake cam on my 4age 16v to a 20v exhaust cam, going to get the cam base cut to 16v size so it will remain at stock spec of 250deg and 7.6mm lift.

Will i need to re shim?
or modify anything?

ANY time a different cam is installed you should check clearances.

oldeskewltoy wrote:ANY time a different cam is installed you should check clearances.

As xploding-twincam mentioned, to determined the correct shims needed after installing different cams (correct me if i'm wrong), checking clearance is done when the cam is at .050" is that right? Just needed you to refresh me on this subject. Its been more than a decade since I've did cam swaps on these bucket style valvetrains.

Mike

KonaTrueno723 wrote:

oldeskewltoy wrote:ANY time a different cam is installed you should check clearances.

As xploding-twincam mentioned, to determined the correct shims needed after installing different cams (correct me if i'm wrong), checking clearance is done when the cam is at .050" is that right? Just needed you to refresh me on this subject. Its been more than a decade since I've did cam swaps on these bucket style valvetrains.

Mike

this is incorrect... there is no clearance when the cam is engaging the bucket with .050" of lift.

The easiest method of checking valve clearances is when the lobe points directly opposite of the valve, you can check clearances.

You are right..this helps as originally stated by xploding-twincam in regards to cam swapping.
Thanks for the correction oldeskewltoy!

Yes lobe pointing up, which leaves the base of the cam facing the shim, that's where you need to check clearence, what's the most clearence one can have?

The factory service manual, even the pdf that is easily searchable on google has this info in it.

xploding-twincam wrote:Yes lobe pointing up, which leaves the base of the cam facing the shim, that's where you need to check clearence, what's the most clearence one can have?

on a Cold engine:

intake 0.006"-0.010"
exhaust 0.008"-0.012"

I just put bigport cams in my late ae92 4agze, and went through this. I set my more towards the loose side. sometimes you can get away with rearranging the shims around to compensate for other, but if not new ones can start to get pricey. Another way is to find people that just happen to have a couple spare heads laying around, and see if you can take the shims. I have had 2 blown 4age's (in the car when I bought them) and stole the shims/buckets out of them for my GZE. It's not really a bad process unless you don't have the handy tool that allows you to remove the shims from the buckets with the cams still torqued down. If you don't have that tool it can take a while. As you have to remove the cam swap shims and/or buckets then put the cam back in, and check your clearances again. Hope this helps!!