Clutch measurement on late 930 long bell housing

[doozer]

Does anyone know the thickness of the clutch / pressure-plate assembly on the 930 long bell-housing?

Measurement from the flywheel to the top of the pressure-plate.

Thanks a lot!
Todd

[project935]

I have a '78 (long style) pp assembly in the garage ... I'll measure it tonight and post it here.

[doozer]

Thanks! I am trying to fit a Tilton triple Carbon/Carbon and a hydraulic throw out bearing. I decided to go with the long bell housing and move the engine back rather than go short bell housing because the Tilton tech said there would not be enough room. I will also ahve to come up with a custom flywheel that fits and has a V8 crank bolt pattern.

Thanks for all the help
Todd

[project935]

'78 OEM 930 pressure plate

Damn heavy!

Overall height looks to be 3-3/16" or 81mm


Sorry for the poor focus ...

Let me know if you need any other dimensions.

[doozer]

YOU ROCK! Thanks soooo much Project935!!

[project935]

No problem ... just give me a ride if I'm ever in Texas

What are you doing for a starter arrangement? I would think it'll be 930 if you're using a 930 transaxle. Let me know if you need the 930 ring gear height/width, OD, and tooth depth count. I can get to that later this weekend ...

Been awhile since I worked on a Chevy V8 - do the starters mount to the block or the bellhousing? If the block, you could maybe adapt the 930 trans housing or whatever adapter plate you're using to clear the Chevy starter and then have a Chevy style ring gear on your custom flywheel.

[doozer]

Thanks! Hell I will let you drive!

It would be great to have that info!

The starter is mounted on the 930 trans and is going to be replace with a Tilton gear reduction unit.

The flywheel will have to be custom unit.... Hey if you get the chance could you measure the exact diminsion from where the flywheel mates to the porsche engine to the friction surface of the flywheel (thickness)

I think I will have to do a custom offset because the V8 crank protrudes a little.

Thanks
Todd

[project935]

No problem ... I'll get you those dims later this weekend.

If you ever need one for reference, I could send you the used-up '78 930 flywheel I have ... but the dimensions are probably all you'll ever need. Hell I could CAD design your custom flywheel if needed ... I do that for a living. I'd need some of the Chevy/Tilton dimensions to finish it off. I could send you a 3D IGES/STEP file which any competant machine shop could CNC machine ... or give it to Tilton to finish off with the clutch steel details they plan on using.

Let me know.

[doozer]

A god among men......

I may take you up on that!

Thank you sooo much!

[doozer]

Hay, what are you using for wheels on your 935?

I have a set of 3 pice gold BBS wheels in 8x16 and 10x16 that came off of a turbo I once had - they have the centers that look like a knock off hub but it is really a spin on plate that covers the 5 lugs

[H20911]

Have you talked to kennedy eng? Brett could advise you on the way to go and build your flywheel.
with the hp that you have you will have a hard time hooking up at all.

[RarlyL8]

Both Renagaid Hybrids and Rod Simpson Hybrids have done what you propose. Rod Simpson loves to talk PorChev and I'm sure would help you out with tips on what works - and more importantly, what to avoid.

[beepbeep]

I saw this thread too late. We have brand new 88' 930 clutch and gearbox dissassembled, so we can do any measurments you like.

About starter and flywheel problematics, we too had to "reinvent the wheel".

First of all, forget about using anything but stock 911 starter. 930 bellhousing is tight and you cannot mount any other kind of starter there.

We machined the flywheel until it was so thick that OEM 930 ring gear was on it's right place. That solved all other problems: when ring-gear is right then starter engagement is right, so is throwout bearing and clutch clearence.

This is flywheel before machining:


After machining (and 60% lighter), with new holes drilled to accept 930 clutch:


With 930 clutch-package and ring gear installed in place:



It can all be solved with little common sense.

Stock rubber-damped 930 clutch is very thick, so is it's bell housing so I'm very certain you can install any clutch you please. Your main problem will be position of starter ring gear. You can solve it by using some sort of adapter between ring gear and your custom pressure-plate.

Frankly, I believe easiest way of solving your clutch problem would be to obtain strongest clutch package that can be fitted on original 930. Then it's just a matter of machining your flywheel until ring gear is on correct distance. I believe Renegade Hybrids already have correct flywheels in stock.

[doozer]

I actually have a Renegade Hybrids flywheel ( for 915 ) but the problem is the Tilton triple plate Carbon/Carbon clutch ( the one I am going to use ) has to have some special groovs cut in it to accept the disk cage.. I guess my best bet would be to get a Renegades 930 flywheel and machine the proper grooves in it.. This may be the simplest solution.. My inital quest for a custom flywheel was because I was going to try and fit the Tilton in a short bell housing 930 trans but now that I have decided to just move the engine back 1.200" I can use the bigger long bell housing 930 trans..
This I think solves a lot of problems..

[doozer]

Goran, can I use some of these (your) photos on my site to help document what I am doing?

Thanks
Todd

[doozer]

I guess what I need to know is the diffrence in offset ( crank to friction surface ) from an OEM 930 flywheel and a Renegade 930 conversion flywheel.

If they are the same or close I should be able to use it. If there is a great diffrence in offset then I will be concerned about fitting the Tilton..

By the way.. You guys have been great and thanks for all of the help!!

Todd

[doozer]

I just got the measurement on a Renegade 915 flywheel from crank to friction surface and it is 0.45"..

Anyone have an OEM 915 flywheel that they could measure for me from crank to friction surface????

Thanks
Todd

[project935]

The 930 ring gear specs are;
142 teeth - 11" OD
Max of 2.5" back from the flywheel surface - 5/16" thick towards the flywheel surface
7mm pitch between the top of the tooth centers, teeth are 4mm deep

915 flywheel crank to friction surface is 22mm

930 flywheel crank to friction surface is 22mm

I might be interested in your BBS wheels ... I'm still looking for something. Can you e-mail me some pics and prices to racer6692@yahoo.com ...

[doozer]

I don't understand 2.5" back from flywheel surface?

Thank you so much for the dimensions!!

Yes I will take some photos when I go out to my shop on monday..

Thanks
Todd

[project935]

Here's a quick layout sketch w/dimensions ... hope this explains it a bit better. I don't have a 930 engine - so I measured my 2.7L for RFOB-to-crank depth.


I have a 930 long housing trans, so I also measured that max depth (to the bosses for the T/O bearing fork shaft and starter mounting area).