Jump to content
Kingpin32

Mechanical clutch and 5 speed

14 posts / 465 viewsLast Reply

Recommended Posts

We have a 68 1600 with the original 4 speed. We would like to do rally’s with it and are opting for a 5 speed. We really like the originality of the car and don’t want to change the pedal box. It has a mechanical clutch and was wondering what can be done to make a 5 speed work with this. Anyway here is a photo of the car all help would be great thanks! 

156EA139-F173-4920-B4C6-BA624E6D67BD.jpeg

9E7639AE-B474-463C-8798-1ED52E7B4D53.jpeg

  • Like 3

Share this post


Link to post
Share on other sites

Describing which 5 speed will help you get an accurate answer. -KB

Share this post


Link to post
Share on other sites

Your pressure plate should be the coil spring (early style) design that was used up until about March 1969, along with the six bolt flywheel and crankshaft.  While the disk itself is the same, the coil spring pressure plate uses a different throwout bearing than the diaphragm clutch used on later cars.  Early 2002s used the same coil spring pressure plate (only larger diameter) so I'm sure someone on the FAQ has fitted a 5 speed to a '68 or early '69 with this clutch setup and can tell you which throwout bearing to use. 

 

I'd like to know myself in case I ever decide to put a 5 speed in my Feb '69 production 2002 without having to change the crankshaft, flywheel and clutch assembly...

 

mike

  • Like 2

Share this post


Link to post
Share on other sites

To utilize the mechanical clutch with a 5 speed would require a early getrag 235 close ratio gearbox due to the throw out bearing fork arm location in the bell housing.

If you plan on using the later E21 transmission it will require a E 21 clutch slave and you will need to change the pedal box for the later type with a clutch master mount.

  • Thanks 1

Share this post


Link to post
Share on other sites

Anything's possible- you could mount the hydraulic master under the hood, and actuate it 

remotely.  But I agree with Jeff- only an earlier 235 would work with your complete linkage.

 

I suppose you could modify the 245 bellhousing to use the 235 release fork...  

 

t

 

  • Thanks 1

Share this post


Link to post
Share on other sites
11 hours ago, Jeff said:

If you plan on using the later E21 transmission it will require a E 21 clutch slave and you will need to change the pedal box for the later type with a clutch master mount.

If using this setup (i.e. the hydraulic clutch activation as found on 2002s), what throwout bearing would you use that's compatible with the early coil spring pressure plate?  Someday I may want to put an O/D 5 speed in my '69, built 400 cars before they switched to the 8 bolt flywheel and diaphragm clutch...

 

mike

 

 

Share this post


Link to post
Share on other sites

I would really like something with an over drive 5th.  I hear a lot about the Getrag 245. So that is what I was thinking. I think modifying the bell-housing yo accept a 235 clutch fork would be the best.  Just curious if anyone has done this before 

Share this post


Link to post
Share on other sites

Cutting the hole for the arm would be the easy part.  installing a Fulcrum/pivot would be a bit more difficult as you would need to mount it to the housing. You would need to research the strength of the housing on a gearbox not intended to have that kind of load put into it in that location.  Probably not a do-it-yourself at home project for the Non Fabricator.   

Share this post


Link to post
Share on other sites
If using this setup (i.e. the hydraulic clutch activation as found on 2002s), what throwout bearing would you use that's compatible with the early coil spring pressure plate?  Someday I may want to put an O/D 5 speed in my '69, built 400 cars before they switched to the 8 bolt flywheel and diaphragm clutch...
 
mike
 
 

I’m not sure what the throwout bearing is used with the early clutch. There are two different off set throwout bearing depending on the clutch used. The 215mm clutch or the 228mm clutch. You should measure your throwout bearing offset before choosing

Share this post


Link to post
Share on other sites
8 hours ago, Jeff said:

There are two different off set throwout bearing depending on the clutch used. The 215mm clutch or the 228mm clutch. You should measure your throwout bearing offset before choosing

My '69 has its original 228mm, 6 bolt flywheel, with the coil spring pressure plate.  I know the T/O bearing for this pressure plate is different from that used with the diaphragm spring pressure plate and IIRC with that setup you use a T/ O bearing from an E21 323 to work properly with the O/D 5 speed.  What I don't know is what T/O bearing you'd use with the O/D E21 5 speed mated to a coil spring pressure plate...

 

mike 

Share this post


Link to post
Share on other sites
19 hours ago, Preyupy said:

 Probably not a do-it-yourself at home project for the Non Fabricator.   

 

Whups- you're right, Byron, not everyone keeps a Bridgeport in the barn...

 

Mike, as to a throwout bearing, the only way to know for sure would be to measure everything.

I've only taken apart 1 6- bolt clutch, and I didn't think to get dimensions from it.  

I do sort of recall that the diameter of the bearing itself was larger, so a later bearing

wouldn't work no matter its set- up height.  But that was a long time ago...  in a hurry.

 

t

 

Share this post


Link to post
Share on other sites

I have modified 4-5 6 bolt flywheels to accept the later diaphragm style 228 mm pressure plates over the years. It’s not that hard if you “have a Bridgeport in the barn”. 

Share this post


Link to post
Share on other sites

As far as the mechanical clutch is concerned, you can only retain it if you use the 235/5 close ratio 5 speed, which is both, rare and expensive. There were 3 versions of the close ratio 5 speed available for the 02s, one version was considered the street version while the other two were considered as the race and rally versions. They only differ in the ratios or lengths of the 1st and 2nd gear. The first gear in particular is much longer or taller in the close ratio 5 speed vs. your stock 4 speed. And, in the "Race" and "Rally" versions the 1st gear is even taller. This was done to give the cars a chance to get a good start out of the hole without having to almost immediately shift into second.

 

You can adopt the hydraulic clutch, but you would need to switch out to the 2002 pedal box and associated booster assembly and booster where the brake master is mounted to the booster. In this scenario, you would have to ditch your existing remote style T50 booster, pedal box mounted brake master, and re-bend your brake lines etc. In your current configuration, it is more difficult finding someone to rebuild your brake master and booster. They are out there, just more expensive to rebuild. I have a 67 1600 with a similar set-up to yours, and I have also decided to leave the original booster and brakes for both originality purposes and because I like all the extra space in the engine compartment that would otherwise be taken up by the more modern booster assembly.

 

Now as far as converting the 1600 to a speed, there are some misconceptions about the similarity of the 1600 clutch assembly to the early 2002 (1968-mid69) 225mm clutch assembly. While similar in principle, they are completely different. The 200mm three prong 1600 clutch assembly, including clutch disk, throw-out bearing and flywheel are all a left over from the earlier NK 1800 and 1800ti. The throwout bearing is also identical to the later throw-out bearing used on the 215mm diagphram clutch of the 2002. And, this 215mm  dighphram pressure plate is identical to the 215mm pressure plate of the 320i including the 5 speed overdrive version. Since the pressure plates are identical in dimension, the throw-out bearings are also identical in the critical dimension of height and diameter. While I have not attempted this, there are a few people on this board who have mated a 320i overdrive 5 speed to the 200mm stock 1600 clutch assembly. Other people who were unsure have torn apart their early 1600 motors and used a 8 bolt crankshaft from the later 1602 ( from 1970-76) along with the larger 215mm flywheel and diaghram pressure plate.

 

Your car looks clean, and the 13" Compagnolos look great. In the end you may opt for the 5 speed close ratio 235/5, but you will be 1:1 in 5th and won't decrease your revs. If you want to achieve that with the close ratio 5 speed, you would need to replace your 4.11 diff with the slightly taller 3.90. But, you have a longneck diff, and while the 4.10 is abundant in the long neck version diff, the 3.90 is rare in the longneck form in the USA. It was used on some 1600ti cars along with the NK 2000ti and 2000CS. But, the drive flange on the NK long necks needs to be replaced with your drive flange, as your deiveshaft is different.

 

The 3.90 diffs are more readily available in the shortneck version, but you will need to replace your rear subframe and driveshaft to include this diff. Many of the 1600 pilots have done this. It sounds scarier than it actually is to do.

 

Another way to decrease revs in your 1600 is to replace the 4.11 longneck diff with the 3.64 longneck diff from the 1968-mid 69 2002. They are easier to find than the 3.90 longneck, and they feel great in 3rd and 4th gear, however you will notice the 12% loss in torque in 1st and 2nd. This is the most economical route, though. And, you might want to give it a try before embarking on the more expensive and labor intensive approaches.

 

So, there you have it.

 

Slavs

  • Thanks 1

Share this post


Link to post
Share on other sites

Another possibility is to adopt the hydraulic clutch by retaining your existing pedal box, booster and brake master. In this case, you will need to modify your existing pedal box to include a mounting location for the clutch master. This was done on my 67 1600 where the fabricator welded on a piece of sheet metal to the back of the pedal box where the clutch slave is mounted. He then drilled holes for the clutch slave bolts. The welded on piece of sheet metal serves as reinforcement for the clutch master mounting location. I was able to convert to a 5 speed without replacing the brake booster and pedal box and rebending the brake lines. I'm running a 2.0L, though. The down side to my set-up is that the older brake components are more expensive to maintain. But, I'm happy with it.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.




×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.