Trans retrofit question.

[joetiii]

I have a 70/71 901 trans installed in my 69.

The clutch seems to be nearing its end. It still pulls fine, but the linkage is set so that the clutch engages high up on the pedal. Before doing a new clutch I'm thinkinga about replacing the cable. I discovered the PO had installed a 70/71 model year clutch cable and cable ends which are different than what is called for in a 69.

Should I be using parts based on a 69? or 70/71?

[Evans, Marv]

Somebody else who knows more about the specifics will probably chime in. The '70 & '71 cars had clutches with the engagement different than other years. I can't remember right now if it was a "push" or "pull" type clutch. Yours was put in the car to use the 225mm pressure plate. So, if yours has been working OK, except for maybe an adjustment to change where it engages, you have to go with the cable that matches the transaxle. So stay with what you have.

[Grady Clay]

Installing a ’70-‘71 type 911 transmission in a ’69 911, replacing the type 901: There are two ways this will work.

1) Changing the clutch, flywheel, ring gear, release bearing, clutch cable, etc. to ’70-71 225 mm clutch.

2) Machining the different pivot location on the ’70-’71 transmission and using the ’69 ball pivot, arm, etc. with the ’69 and earlier 215 mm clutch, flywheel, etc..

I have done this both ways.

It sounds like you have choice 1) if the clutch cable is from a ’70-71. If so, this gives you the larger clutch. That said, it takes careful tinkering to have the ’70-71 clutch operate best possible.

A lot has to do with how carefully the conversion was done. There is a lot of opportunity for mischief from someone who didn’t know.

Here are some links to peruse. While not directly addressing your issue, the info you need is here.


’70-’71 clutch
clutch cable for 70-71 901
and
'70-71 T.O. arm play?
and
http://forums.pelicanparts.com/porsche-911-technical-forum/166598-clutch-cable-70-71-901-a-post1520882.html#post1520882
“How to ID a Type 911 transmission”
How to ID a 911 ty[e transmission tranny
“Moving the clutch lever pivot ball”
Moving the clutch lever pivot ball

“'70 (pull) clutch woes -- help!” Good photos.
'70 (pull) clutch woes -- help!

'70 clutch still broken, help needed to make race
'70 clutch still broken, help needed to make race

911 Gearbox Rebuild Underway. Beadblast?
911 Gearbox Rebuild Underway. Beadblast?


Best,
Grady

[joetiii]

Yeah I kinda figured that the clutch parts should match the trans and not the model year. Since it's only been 3 years and 4,000 miles since the cable and Bullet proof weltmeister cable ends have been replaced, I'm thinking the I need to check where the cable attaches at the rear tube.

If all looks ok it might just be the clutch is near its end. Seems odd that it would deteriorate over a short period of time.

[chuckw951]

Originally posted by joetiii
I have a 70/71 901 trans installed in my 69.

The clutch seems to be nearing its end. It still pulls fine, but the linkage is set so that the clutch engages high up on the pedal. Before doing a new clutch I'm thinkinga about replacing the cable. I discovered the PO had installed a 70/71 model year clutch cable and cable ends which are different than what is called for in a 69.

Should I be using parts based on a 69? or 70/71?

Really? Already? When I did the motor swap I installed a new 70/71 clutch package. Cost like $500... The trans is a 70/71 which is why it has the different clutch cable. I happen to have a brand new 70/71 cable if you need it....though I think the one that we installed during the swap was new. I think you should take a closer look at the linkage.

[joetiii]

Chuck,

Got your PM. I went back to the car's history binder and couldn't find any invoices or slips on the clutch package so I assumed the rebuild was limited to the pedal cluster and the cable. Thats why I PM'd and thought the clutch was on its way out.

Anyway, the car left me stranded on Friday. When I came to a stop, the clutch pedal stayed down and I heard a rotational wrapping noise. (that's around here in a different thread). At first I thought it was the clutch cable but apparently something else snapped and the clutch fork is hitting against the disc. (prssure plate?) I've got the the entire assembly coming out so we can get inside and discover what broke. It'll be a quick pit stop if the guys at Musante Motorsport can get it together by friday afternoon. I'm signed up for CVR PCA "Car Control Clinic" and "autocross" on Sunday. Stay tuned

[chuckw951]

Joe,

Sorry that the car left you stranded. Gotta love "pushing a Porsche" I've been there before.

That is one receipt that I didn't have in the binder. The person that did the engine swap was in NC so I had the clutch package sent directly to him. It was from German Parts and Restoration I believe. I suppose it is possible that the clutch it toast but I guess you will not for certain until you get in there.

The good news is that the engine/trans is fairly easy to remove.

Good luck....the 69 911E 3.0 is a fun car to drive.

Chuck

Originally posted by joetiii
Chuck,

Got your PM. I went back to the car's history binder and couldn't find any invoices or slips on the clutch package so I assumed the rebuild was limited to the pedal cluster and the cable. Thats why I PM'd and thought the clutch was on its way out.

Anyway, the car left me stranded on Friday. When I came to a stop, the clutch pedal stayed down and I heard a rotational wrapping noise. (that's around here in a different thread). At first I thought it was the clutch cable but apparently something else snapped and the clutch fork is hitting against the disc. (prssure plate?) I've got the the entire assembly coming out so we can get inside and discover what broke. It'll be a quick pit stop if the guys at Musante Motorsport can get it together by friday afternoon. I'm signed up for CVR PCA "Car Control Clinic" and "autocross" on Sunday. Stay tuned

[joetiii]

Looks like the fork pivot failed and startled rattling around inside the housing. The flywheel is looking pretty bad from all this. The shop thinks there is wear equivalent to the amount of miles that we think is on the clutch. Chime in here Chuck on the clutch pkg relacement. The odometer now says 104,000 and the rivets are starting to show.

[chuckw951]

Originally posted by joetiii
Looks like the fork pivot failed and startled rattling around inside the housing. The flywheel is looking pretty bad from all this. The shop thinks there is wear equivalent to the amount of miles that we think is on the clutch. Chime in here Chuck on the clutch pkg relacement. The odometer now says 104,000 and the rivets are starting to show.

Well I did the swap and put 3000 miles on the car, I think the odometer was around 95K at that time. I can't say that the clutch had an easy life so maybe you should replace it while you are in there and not worry about it for a while?