Valve train, Information Options

[sjhenry1075]

Hey everyone,

I apologize if this is common knowledge, I am just trying to learn my one thing for the day.

So I am building a 2056 and I just need a little more information regarding rockers/swivel foot adjusters, 8mm vs 10mm adjusting screws, etc..

I currently have a stock 1.7 that came with my 71, but I am also building a 2056 that will have dual 40 IDF's, 86a cam, and 2.0 heads with 44/38 valves.

I keep reading about using 1.7 rockers. Are they referring to the rockers on 1.7 engines? What is the benefit to using swivel foot adjusters? 911 adjusters?

I am really trying to learn as much as possible about these engines and each component.

[brant]

the 1.7 rockers already have the correct thread size to accept swivel feet adjusters
they will need to be machined slightly to work and give you correct range of adjustment
there are threads about how to machine them, and you can even use a grinder to get that clearance.

the later 2.0 motors use a different thread size so can not accept swivel feet.
I believe there may be an aftermarket swivel feet made for them currently

the advantage of the swivel foot is that it swivels/flexes to better make contact at the correct angle with the valve stem

so better fitment.. more even wear... and slightly better alignment in the valve trail
potentially with less wear they will maintain that clearance setting better.

you need to also measure and make custom pushrods during assembly to get equal lift on each of the 8 rockers.

search valve train geometry threads.

[cgnj]

You have correct rockers for 911 swivel feet. They have to be machined to accomodate the 911 adjusters. there are threads that detail the machining.

The 10mm adjusters work with 2.0 & 1.8 rockers. They also need to be machined. You would have to order them from Germany or find a seller on TheSamba.

The 1.7 rockers with 911 feet. Easy button

[rfinegan]

I was in the opinion that the new SS valves are not has hard as the hardened Rocker tips on both the 1.7 (8mm)and 2.0 10(mm)rocker arms
The 911 swivel rockers and be easily fitted to the 1.7 rocker shaft with a few machined cuts and will reduce the wear to the valves. More Important with higher lift cams. These 911 swivels are a Few $$ more than the after market ones but have YEARS or dependable history.
After makers are now avaialbe in 8mm and 10mm for 1.7 and 2.0 shafts and the feed back has been pretty good. So either should be ok

[914werke]

What hasnt been mentioned is they (adjusters) are also lighter that the 1.8-2.0L solid versions = better

[sjhenry1075]

Thank you for all the replies, it's definitely helpful!