are the ceramic lifters longer than the stock ones?
should the push rods be special?
rocker arms from 1.7 L with scat floppy foot adjusters.
It does not fit correctly What should I do?

Bernie

The ceramics have the same pushrod height as a Hydraulic lifter. This is to allow a shorter pushr oand cut down on reciprocating mass.

You will definately need custom length pushrods, but thats no biggie because stockers won't normally do anything for the rocker geometry when matched to an engine without a stock cam, an engine that has any cylinder shim, or an engine that has had head gaskets removed, or heads resurfaced.. All these things change the optimum pushrod length, and coupled together create a challenge..

I can help you through the geometry process, it kills valve guides if done incorrectly or done without the right idea in mind.

thanks Jake
My son asked me to post this message to find out the problem. you would start by cutting down the push rods?

I'd like to hear more too Jake. I've got ceramic drop-ins coming this week. I decided to remove and send back Web's "performance" lifters instead of firing it up to see what happens. Not worth the risk.

I'm getting JohnC's HD AL rods.

Now what?

Where can I find some ?

As far as the ceramic lifters are concerned, the newest batches have stock pushrod height unless you order the race version that has reduced rocker box oiling @ high rpms which is the only one that has a raised pushrod cup height. If there is some concern over which custom cut-to-length pushrods to use, both the HD aluminum and Manton pushrods from aircooled.net will work fine, but as Jake said, setting up the geometry is probably the single most important step in this process. An adjustable pushrod might help figure out the proper length. Aircooled.net sells those too!

Charles Navarro
LN Engineering
http://www.LNengineering.com
Aircooled Precision Performance

I have heard that the only way to go is to get real 911 valve lugs, and that using pretty much anyone else's stands a fair chance of making you very unhappy.

Second, none of the non-stock lugs will fit correctly in an unmodified rocker arm. You will need to take some material (I see the number 0.060" frequently) off of the face of the rocker arm, the part that gets closest to the valve stem. That's to make room for the swivel foot.

Third, there is a good chance you will need to put some kind of shim in between the rocker stands and the head.

Fourth, you may need to change the length of the pushrods due to any and all of the above factors.

Fifth, the only way to tell what of the above you need to do is to go through the whole process of setting up the valve train geometry. Which has been mentioned above, and is probably described around here somewhere.

--DD

Grinding off the foot .060 will help the problem as there is not enough room between the valve and foot. What is the best way to do this? could you use a grinding wheel? Are there longer studs for the rocker arms so the taper still fits if you shim the bottom?

Bernie

Hi,
This may help. Will allow you to see what you are trying to accomplish with the adjustable pushrod.

Carlos

The board has the .pdf attachment freaked out.

The board just stripped the file extension. Right click on the attachment and "save as" rocker_geometry.pdf into some folder. You'll be able to read it fine then.

Grind the bottom side of the rocker arm, where the swivel contacts it. That way the adjuster will retract farther. A fixture in a milling machine is the best way, but if you are careful a hand grinder will work.
Longer studs should be unnecessary, as the optimum shim height will only be around .040-.080"
The simple explanation for setting up the valve geometry is to get the adjuster perfectly in line with the valve stem when the valve is at half of total lift.
I cut a stock pushrod in half, threaded both halves, and reassembled it, so I could install it and adjust the length as I did my testing.
You should use a weak "dummy" valve spring while doing this. What I use is rocker shaft springs.