How to lighten clutch pressure on 308

I have read that myself. In 1980 Ferrari changed the pedal pivot design to reduce pressure by 20%. Only certain chassis #'s can be modified according to the article. I think it was in a PH magazine. I'll dig around for you.

 

There was a letter on this in the October 2000 issue of Forza, page 30. Basically the modification involved using the updated clutch lever (part #116472) at the bell housing.

If you want, I can scan/email the article. The issue may be out of print at this point.

Or, the other option...
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Your post makes me wonder if anyone has ever installed a hudraulic clutch in a 308. Master-Slave-Line and a few custom mounts and linkages. Probably wouldn't be too difficult.

 

From the Service Bulletin, see bulletin page 37:
http://www.icbm.org/erkson/personal/cavallino_rampante/Service%20Bulletins%201981-82%20All%20models.pdf

 

Hello all,

it's not only the required force which makes driving through heavy traffic some kind of exhaustive. It's also the long travel of the clutch pedal compared to more common cars. And the level of the pedal arrangement also doesn't help. I have the later design on my 308 and can state, that this design improvement didn't solve the problem completely.

Best Regards from Germany

Martin

 

Martin, the longer travel is what adds to the leverage. More leverage lightens the input load, not unlike trying to move a rock. A longer lever requires less effort to do more work, but requires more travel. I believe the updated design was simply to alter the angle of the pedal arm, but the stroke remains the same?

The early 308 has an overcenter spring incorporated into the linkage at the clutch bell housing. It should be adjusted to be just past center with the spring just starting to decompress, and the spring adjuster tightened as far as possible without binding. Also make sure all pivot points are lubricated. The overcenter spring reduces pedal pressure once your overcenter, but does require more initial force to get past it.

And once again everybody, its not a Honda. We are dealing with much greater horsepower and torque, and it requires a much stouter clutch. No matter if you use hydraulics, push rods, or cables, the principle leverage is equal. The pedal travel distance:clutch throwout distance ratio is what determines the pedal effort, based upon the wieght of the pressure plate. The only possible advantages to hydraulics or cables would be the drag involved in the effort. Once the pedal is down to the floor, all designs would have the same load on your foot provided they use the same leverage.

 

looking over the 308 and Mondi linkage cut sheets the effort is the same or should be the same between the two. Having used both I'd say it didn't feel different to me other than the 'smoothness' associated with the hydraulics of the Mondi. If you switch to hydraulics all you need is some parts off a Mondi.

 

Hi
The Service Bulletins are on http://dino308gt4.com as well. My set was scanned by Rob Garven.

Gerrit
http://dino308gt4.com

 

Try changing the clutch cable... or at least lubricating it well.. (get inside the LH wheel arch, pull up the rubber sleeve and squirt something like M/cycle chain lube in... get an assisitant to pump the clutch to draw the lube into it)

the inner cables cut a chanel for themselves within the outer cable lining, which makes them progressively heavier.

I changed one recently that had broken at the little wheel near the adjuster, I couldn't believe the difference just a new cable made... didn't touch adjustment...

 

dismantling, thorough cleaning and lubricating with grease makes it act like new.

Best Regards from Germany

Martin

 

If the pulley wheel doesn't rotate freely, then not only does the clutch feel heavy, but the cable gradually saws itself in half...I know this from experience!

 

on a 1980 308 I futzed around with, the bell crank mod was already done. Heavy clutch. I relocated the clutch pedal spring, not much difference. Replaced the pressure plate with a 328 one....huge difference.

the tsb called for replacing the clutch pedal (for the spring attach point), the bell crank arm, the pressure plate, the TO bearing and carrier. Why the carrier I don't remember...I didn't change it because it was unclear whether it was the old one or newer one. I did change the TO bearing.

 

Phil, what is the different between the 308 and the 328 preasure plate? Also is the clutch disc and TO bearing the same?

 

keep in mind the following is comparing:
1] what came out of the 308 the first time I changed the clutch
2] the valeo kit sold by george evans in ohio (which others have commented on)
3] a borg-and-beck kit I got for my 328 from gt car parts which I put into the 308.

I don't know what you'd get from a dealer or other parts vendors.

I think [1] and [2] above were the same.

in [3], the TO bearing was different. On the 328, the face of the bearing that is constantly in contact with the pplate can spin independently of the outer/inner races of the TO bearing. I assume this is the same for the qv and any 308 with a constant contact TO bearing.

The pplates look about the same, but the effort required to depress the release fingers is different. Whether that means the clamping force is different, or it's just a design difference I don't know.

the clutch disc appeared to be the same.

If anyone wants/needs the valeo pplate to test/compare, I don't need it. It's got around 1K miles on it. pm me.

 

Benjamin, can you post some photo of the new bellcrank assembly perhaps the before and after if not just the after, Thanks