What did I buy? Help

Lukesportsman · 02-03-2007, 12:53 PM

Ok, so the day was going well. The OBX headers actually fit!

Then I got out the clutch parts and all h$ll broke loose. Can you guys help me figure out what I bought? I'm trying to put a clutch package together for my 81' 3.0 SC 9 bolt crank.

Here is what I thought it should look (end of my 3.2):

Here is what my new flywheel looks like that I bought from fellow Pelican for this application:

My starter ring won't bolt or fit:

The Sach clutch is much smaller:

Finally the bolt pattern of the Sach pressure plate is smaller. Imagine that the other side bolts line up visually:

Lukesportsman · 02-03-2007, 01:03 PM

Ok, my internet connection stinks so I just wanted to make sure I got all the photos up. I took the measurements in inches so there maybe so error in conversion off a tape measure, but at this point I don't think small details are going to matter.

Hand etched part number in flywheel: P4 1174

Starter ring measures: 10 7/8" or 276mm
Clutch : 8 7/8" or 225mm
Flywheel diameter: 11" or 279.4mm
Flywheel step: 10 1/2" or 266.7mm
Flywheel clutch surface: 9 1/2" or 241mm

Just a few more pictures for a helpful hint:

Any help would be greatly appreciated.

SP2 · 02-03-2007, 02:12 PM

I am doing the same project this weekend. Can you not compare your old clutch and flywheel with the new stuff? The clutch loos right, but the flywheel looks to be the part that is off. Obviously too big. By the way, you know that the starter ring goes on top of the pressure plate, and the pressure plate bolts go thru the starter ring and the pressure plate. Looks like one or the other needs to be returned.

Lukesportsman · 02-03-2007, 02:32 PM

James,
I don't have an old 3.0 clutch/flywheel to compare. My 3.2 is still mounted, but of course it is a little different with the Motronic stuff. I didn't try to place them in the correct orientation, but set them out just to show size in reference to bolt holes. Could of done better, I suppose. Thanks for your input.

Yes, I agree the flywheel seems to be the oddball of the three parts and since that is the part bought from an individual it also makes it suspect.

Can anyone identify the flywheel? Could it be a 930? or a G50 (i doubt)? Why does the center look so different without room (?) for the pilot bearing bolts?

Lukesportsman · 02-04-2007, 10:18 AM

Can't anyone identify the flywheel? Anyone know the application?

The pilot bushing tube area looks unusual and maybe like an earlier crank? I can't remember what the 2.7 looks like, but obviously it has 9 wholes since I can count that high

Eagledriver · 02-04-2007, 07:21 PM

The pressure plate looks right. I suspect you have the wrong flywheel. I don't know what a G50 flywheel looks like but I bet that's what you have.

-Andy

1972_911T · 02-05-2007, 05:50 PM

Quote:

Originally posted by Eagledriver
The pressure plate looks right. I suspect you have the wrong flywheel. I don't know what a G50 flywheel looks like but I bet that's what you have.

-Andy

Its not a G50 flywheel because it does not have the raised bumps on the outer edge for the DME sensors maybe a turbo flywheel as these were also bigger than the 915 type. Does it not have a part number cast into the back of the flywheel?

Steve

Lukesportsman · 02-05-2007, 07:07 PM

I will look again, but I couldn't find anything before beyond the hand etch number above. I think its a Fidanza flywheel. I could try contacting them, but without a part number I doubt I would get a meaningful answer from a generic tech helper.

Sure, it would seem that the lact of Motronic teeth would rule out both 3.2 and G50 up use. I still wonder about the turbo issue and I just might be able to use that later with the 930 box I just don't know. The 240mm diameter I think correlates with the 930.

The small pilot bearing hole is throwing me too. Wouldn't the 3.3 crank be similar to a 3.0SC or 3.2? I would have thought someone could've nailed this by now.

MBEngineering · 02-06-2007, 03:53 AM

HI Luke the flywheel looks to fit a 3.3 turbo early as the spigot bearing is the old type to press in to the flywheel and not the bolt on type you have, if require it for a 3.2 with motronic, no good as you have no teeth for the sensors and the clutch to fit will be the larger turbo/g50 box type, with the bolt pattern you have in the photo, do you have a 915 or G50 box?? The 3.2 engine with a 915 or a G50 both have to have teeth on the flywheel for the sensors and both have different clutches and flywheels.

regards mike

Lukesportsman · 02-06-2007, 01:15 PM

Now we might be getting somewhere, thanks Mike.

This application is for a 78-79 915 behind a 3.0 with bolt on pilot bearing tube. So I guess I'll order up a new lightweight flywheel for this application to go with the Sach's clutch setup.

Now, I'm thinking to use a 930 long bell-housing behind the turbo build up. COULD I maybe getting lucky and use this for my NON Motronic 3.2 based (86') mated up to a 930 box? I had planned a steel flywheel for durability but if I own an Al one, why not burn it up before investing in another.

Can I use a press in pilot bearing like whats in my 2.7? I don't know the differences/similarities of the crank end machine work. I'd like to make this work since I own it and its new, if not one application than strangely maybe the other :O

cab83_750 · 02-06-2007, 05:24 PM

Luke,

I have an '83 and had the sam dilemna with the flywheel. I did not get much assistance, so I decided to buy what you referred to as pressed-in pilot bearing..........and............it worked for me!

Good luck.

cab83_750 · 02-06-2007, 05:33 PM

Luke,

Check out this thread for pics of my clutch package.

High performance Clutch/pressure plate?

Ken911 · 02-06-2007, 07:10 PM

when you pull out the old flywheel why not get it resurfaced? I did the one in my 3.2 works fine. didnt cost much either less than $60.00

Lukesportsman · 02-07-2007, 03:30 PM

I appreciate the thought Ken.

My 3.0 has no flywheel. My current engine in car is 6 bolt 2.4(big bore) with great but unuseable flywheel/clutchsetup.

My 3.2 flywheel might very well be saveable but is being mated up to 930 box.

It is for the 3.0 I'm assembling at this time. I now conclude that the flywheel is going to be replaced. I'm just trying to identify the flywheels application since it might be a 3.3Turbo and if so it might be applicable to the 3.2/930 box application.

Thanks for all the help to all above. I'm still following if someone can add more.

Ken911 · 02-07-2007, 04:51 PM

it doesnt look like the one in my 3.3 turbo either yours has rivited wear surfaces the flywheel in my turbo didnt look like that

Lukesportsman · 02-08-2007, 06:33 PM

Ken,

Thanks for looking, this is an aluminum flywheel and is the usual method of attachment.

Ken911 · 02-08-2007, 08:11 PM

ohok mine has the stock steel flywheel

Lukesportsman · 02-11-2007, 01:39 PM

I'm pretty sure I've narrowed it down. 240mm clutch surface indicates a turbo, agreed. 9 bolts signals post 77 crank. Small press in pilot bearing points towards 78-79 as some 79 started to use bolt on pilot bearing tube.

My tentative answer: 78-79 3.3 turbo flywheel w/press in pilot