engine builder question

[michaelaiellosr]

I have a 73 2.4 case, machined a few years ago for a rebuild. I need to source a lay shaft and its crank gear. What do I need to know for the two to match ? There are no markings I can detect on the case. Appreciate all constructive comments and any help. Mike

[Frank Beck]

You may want to consider a straight-cut gear setup. Only drawback is that it has a little whine to it. If you like the noise of a 6-71 blower on a street rod it's better than Bohemian Rhapsody.

[michaelaiellosr]

I was considering this one, but would like to know more about the lack of a code for the match gear on the crank...

"Early Porsche 911 Intermediate Shaft Price: $350
This ad is for a used OEM intermediate shaft (layshaft) with an aluminum intermediate shaft gear for what I believe to be is 1965 - 1973 Porsche 911 T E S with a 2.0 liter motor and or a 2.2 liter motor and possibly a 2.4 liter motor but please do your homework to insure this is the correct part for your needs. There is a 0 (zero) stamped on the aluminum gear and I assume it is a shaft size code.

As for as I can tell the intermediate shaft is in good condition and doesn't show any signs of wear and tear. I did see some roughness on three or four of the gear teeth on the large wheel but nothing that stood out. I have the drive shaft and the oil pump if you need those items too.

The Porsche part number for this part is I believe 901.105.013.01. "

[chiroracer]

That shaft is for alum case with no bearings. The shaft you need is plentiful and cheaper. As I have read and been told there are 0 and 1 size groups for the gears and you want them to match ,most builders use a calibrated feel to ensure there is a very slight play when they are installed in the case half with no binding. S

[gled49]

No, the shaft pictured is for the later cases with bearings. You have to test and measure gear backlash to know for sure. This part needs to be new if only the gears are replaced on the shaft, too important to not to be perfect. I remove the gears and measure the runout on the shaft, .05mm max. Install new gears and your good. Gordon

[xpensivewino]

so a later lay shaft, lets say SC vintage, can't be run in a non bearing mag case? I thought all the lay shafts were the same as long as you match the 0 to 0 and 1 to 1's? How does the later style lay shaft differ dimensionally from and early style?

[Jon B]

so a later lay shaft, lets say SC vintage, can't be run in a non bearing mag case? I thought all the lay shafts were the same as long as you match the 0 to 0 and 1 to 1's? How does the later style lay shaft differ dimensionally from and early style?

An SC intermediate shaft can be used in a "non bearing mag case" (68/69).
The "non bearing mag case" actually did have rear bearing shells, but did not have front bearing shells.

The first intermediate shafts, through 1967, had much larger rear journals, were extended rearward for endplay adjustment, and had a different gear offset than later intermediate shafts.

Jon B.
Vista, CA.

[tom1394racing]

I can supply a matching intermediate shaft/crank gear pair.

PM me for details

[66S]

Dont buy from anybody who describes an int. shaft as fitting 65-73.

[xpensivewino]

buy it from Tom, great to deal with and always has what you need...