P258 Diff Tool Material?

tocobill · 02-11-2019, 01:39 PM

Anyone have an idea on what material Porsche used to make there P258 Diff tool from? Trying to figure out if the machinist needs to order ceramic tooling or can get away with carbide tooling. Thanks.

ajwans · 02-11-2019, 02:25 PM

Ingenious folks have made these from old diffs. I'm pretty sure mild steel/carbide tooling will be fine, all you need for the P258 dimensional accuracy and regular steel will be more than rigid enough vs your dial indicator spring.

Check out these guys Porsche P258 pinion tool

Please post what you come up with, I've been thinking about making one of these for myself.

andy

tocobill · 02-11-2019, 02:31 PM

Yeah, Ive have seen a few modified diff. I have also seen the VW289 modified to be a P258. I got one cheap so that the route Im headed. Have the dimensions .. just need to turn it. Having a hard time finding someone who is familiar with cutting with ceramic. Have a local guy Im working worth, but he wanted to know the tool material. Ive been told its hardened, but wanted to confirm if possible.

ajwans · 02-11-2019, 02:41 PM

I'd be interested to see how this turns out. I had a VW289 but decided not to rework it because there just didn't seem to be much material left once the journals were resized.

The width was a ways off too IIRC.

andy

tocobill · 02-11-2019, 02:44 PM

Evan did this a while back and worked pretty well. You are correct the width needs to be cut down to 120mm.

915 rebuild and ITB/EFI project, here we go!

ajwans · 02-11-2019, 02:48 PM

My bad, I assumed you'd be using this for a 901, the journals are probably already correct or close for 911/915 bearings.

Good luck

andy

oldie44 · 02-12-2019, 01:50 AM

The P258 tool uses the same casting as the VW289d; it is just machined differently.
I think the VW 289d tool is hardened after machining. It can be reworked with normal tools but does not cut easily.

tocobill · 02-12-2019, 06:27 AM

Thanks. That is was my thought too. Machinist has ordered a hardness tester to see which route we will take.

kevingross · 02-12-2019, 11:15 AM

Curious to know why you're repro'ing the P258 when you could purchase the VW385 tools to do the job.

tocobill · 02-12-2019, 12:09 PM

When I looked at the VW385 a couple years ago I had to go through a dealer for the Snap On site. It was like pulling teeth to get a new tool. Some parts were NLA or Out of Stock. The complete kit goes for $5K and maybe $3K if you can find just the mandrel and associated parts need for the 915 trans. I got a VW289d tool for $150 with all the parts. Have it machined to P258 tool specs for $120. Total in tool is under $300. Even the machined diff tools are over $800. Easy math.

kevingross · 02-12-2019, 04:37 PM

Quote:

Originally Posted by tocobill

When I looked at the VW385 a couple years ago I had to go through a dealer for the Snap On site. It was like pulling teeth to get a new tool. Some parts were NLA or Out of Stock. The complete kit goes for $5K and maybe $3K if you can find just the mandrel and associated parts need for the 915 trans. I got a VW289d tool for $150 with all the parts. Have it machined to P258 tool specs for $120. Total in tool is under $300. Even the machined diff tools are over $800. Easy math.

Bill, makes sense especially if you anticipate working on a single (model) of car. For my needs, which are a whole range of transmissions from early 911's to present models, the VW385 and all its add-ons has made sense. But I get it, your math makes good sense.

If Snap-on is out of stock, btw, worth checking with Zelenda. I've bought my Porsche/VW/Audi special tools from them for a long time, they are good people.

Cheers,

tocobill · 02-12-2019, 04:53 PM

Thanks Kevin. I’ll keep them in mind in the future.