Chain sprocket alignment

[1fastredsc]

I'm up to the point in the rebuild book where it says to measure the intermediate shaft for chain sprocket alignment. My question is if the later 911's can measure up to the end of the intermediate shaft, why do the early cases have to measure through the access hole to the intermediate sprocket?

[1fastredsc]

I also want to add that the bentley books says to align it using the later model measurement, don't know why though. I need help before i make a mistake.

[1fastredsc]

No one has an answer to this?

[hobieboy]

I am in similar situation so am keen to see if I understand it correctly too...

The BA book said that Porsche changed the crankcase ~1983 hence the new method (measure face of shaft as opposed to face of sprocket of the shaft).

Seems to me that the access hole is gone on the newer crankcase.

So, beware that the offset is different. The old style means right side distance should be the same, but the new style means you have to add some offsets.

[Wayne 962]

Right - the measurement hole isn't there on the later cases, hence the new method. There's also a typo in the book in this section, check the corrections page:

http://www.101projects.com/911-Rebuild/corrections.htm

The Stomski tool is very good for performing this measurement and getting it right...

-Wayne

[126coupe]

I used to make this adj with straight edges, what a pain
I bought the stomski tool, what a great tool!
I ended up w 3 shims on 1 side a 4 on the other.

[nreed]

Where does one procure a Stomski tool?

[nreed]

Dumb question..sorry never mind.

[1fastredsc]

Um, the reason i ask is because instead of the stromski tool, i have a snap-on straight edge and a machinest metric ruler that is indicated to the .5mm and supposed to be accurate to the .1 mm. Obviously i can't use the access hole with the ruler, so i was curious if the later procedure is fine to use on the early SC case?

[markwemple]

With this question, if I keep track of the shim location, do I need to do tis measurement?

[hobieboy]

Not really sure but I noticed that the part #s for intermediate shaft & sprocket were the same from 74-89, so it seems to me that other than blocking off the access hole, the dimension of the 2 must be the same.

[1fastredsc]

Um, so yeah, i guess no one knows for sure.
My initial measurements, measuring to the later style case specs and procedure (to the front of the intermediate shaft). And after the measurements, it came to one shim too many on both sides. So considering how close the measurements are to what they should be on first try, i'm assuming this method will work.
Also, for future reference, maybe i'm dense, but where DO you get a stromski measuring tool?

[nreed]

From Pelican or Stomski www.stomskiracing.com. They have other very nice tools too. For some reason (maybe bulk buying) Pelican is a little cheaper.