Race clutch back to street able clutch

[stubble88]

Converting this Tilton dual race clutch back to stock. Wondering if I can keep this clutch arm arrangement? I believe there should be a return spring here? Also need help ID inv if this flywheel can be used with a stick sachs? Or I need it change that aswell. Sorry. I’m just not familiar with this area of the car just yet. Any help would be appreciated. Thanks

[dannobee]

923/02 gearbox is out of a 912E, IIRC. It takes a push style clutch like a '69 911.

[stownsen914]

Guessing this is in a 911? Based on dannobee's comments, looks like someone may have adapted 912E trans to a 911 because of the push style clutch actuation, to use on the Tilton clutch. A 915 in a 911 uses a pull style clutch actuation. Assuming you're planning to use the usual 911 style clutch, someone here can chime in on what parts will be different between the two tranny types.

[stubble88]

Originally Posted by stownsen914

Guessing this is in a 911? Based on dannobee's comments, looks like someone may have adapted 912E trans to a 911 because of the push style clutch actuation, to use on the Tilton clutch. A 915 in a 911 uses a pull style clutch actuation. Assuming you're planning to use the usual 911 style clutch, someone here can chime in on what parts will be different between the two tranny types.

Yes. Correct. I’m just wondering if I can keep the flywheel and just add a regular sachs clutch?

[john walker's workshop]

The 912e guide tube is smaller than a 915 tube, so ya got a problem there. Looks like a 915 mainshaft was used.

[stubble88]

Why would one want this setup for the track? I guess that’s what Tilton clutch requires. What are the benefits? Trans has a LSD. 915 301 101 11r is the front half of the trans

[stownsen914]

A Tilton clutch is smaller/lighter than a stock clutch and since it's twin plate, probably has a good deal more torque capacity.

To your q about the flywheel, it almost certainly is a specially made one to accommodate the Tilton bolt pattern. Probably won't work with a stock clutch.

[john walker's workshop]

Probably going to need a 915 diff housing swap.

[Evan Fullerton]

Yes, looks like you have a 7.25in Tilton setup. JB Racing or Aasco among others made these. Definitely need stock flywheel, clutch, throw out bearing, and clutch cable arm to go back to the stock pull type arrangement.

Using a 912E 923 trans for racing was common back in the day as a you got a close ratio trans with an electronic speedo 7-31 R&P. Will need to count/measure the input shaft splines to see if a 915 main shaft was built into it or not as the spline size is different and would require a matching/special disk to make work with a normal 225mm 911 clutch/pressure plate setup. 912E clutches are 215mm with a different spline on the disk to fit the smaller flywheel setup of the T4 engine.

[dannobee]

Originally Posted by stubble88

Why would one want this setup for the track? I guess that’s what Tilton clutch requires. What are the benefits? Trans has a LSD. 915 301 101 11r is the front half of the trans

The gear ratios are better for racing. Although the 7:31 ring and pinion is weaker.

I would highly doubt if anything but the starter ring gear would cross over to a "regular" clutch. Plan on buying all new.

[Dan J]

I think you could sell that set up for equal to or more then a stock set up
You might want to post it on the HSR classifieds as that is likely where your buyer is

[Dan J]

By set up I meant clutch, flywheel and trans

[stubble88]

Originally Posted by Dan J

I think you could sell that set up for equal to or more then a stock set up
You might want to post it on the HSR classifieds as that is likely where your buyer is

Yeah. I think you’re correct. Would love to stick with an lsd though.
I think AASE built this trans using parts from ASCO

[stubble88]

Has a small crack here in pic. Guessing this can be welded pretty easily. I have paper work this trans from AASE in the rebuild. Anyone have any advice on the value?

[Nditiz1]

If you search my name I just converted my 923 to a 915 setup and put in what was needed for the conversion. As Evan and others said count your main shaft. If 24 then you have the original main shaft and need to use a 70-71 clutch disc. If it has 20 splines then you are already good for 915 so you can use any 72 - 89 clutch/pressure plate package. I have mine mated to a 75 engine, but could just as easily be a 3.2.

The 923 with a 7:31 ratio is exactly the same gearing as a 74 trans with a slightly taller 4th gear.

[john walker's workshop]

Y'all are missing the guide tube size between 912E and 915. They don't interchange. The hole spacing is wider on the 915 also. The diff housing is 912E only. You can't use a pull style clutch with a 912E diff housing with the smaller guide tube.

[john walker's workshop]

[Nditiz1]

I swapped over to a 915 guide tube and have no problems with my 923 and pull style bearing

[stubble88]

Well. I count 20 splines. Counted twice and marked with sharpie as I went.

[stubble88]