Smallcar bellhousing clutch options

[ALIKA T3]

[Sodo]

Oooops back when I made this image, there were notions that it had a bellows inside (wrong). Here's a cutaway of the metal 0A5141671.

The purpose of this pedal modification:

Moving the hole inward matches the fluid output of the Vanagon master cylinder to the 0A5141761_ GTI clutch slave/bearing.
It is theorized that the larger Vanagon Master Cylinder "overdrives" the 0A5141761_ causing damage. It is likely that drivers who push the pedal hard to the floor, bottoming the slave, 'inflate' the slave, deforming it and breach the slave's static seal (especially on the Plastic version).
With this modification, Smallcar clutch modulation (driving) is soft and silky-smooth.

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'90 Westy EJ25, NEW oil rings (!) 2Peloquins, 3knobs, SyncroShop pressure-oiled pinion-bearing & GT mainshaft, filtered, cooled gearbox.
'87 Tintop w 47k 53k, '12 SmallCar EJ25, cooled filtered original gearbox
....KTMs, GasGas, SPOT mtb

[Franklinstower]

[syncrodoka]

I saw that smallcar was offering stan's headers in 2 different finishes recently. This kind of makes sense now.
Good to hear the new owner trying to improve the business. Product support was pretty poor in the past.

[Sodo]

The main reason for the 13mm hole offset was to match the fluid output of the Vanagon master to the Golf slave.
It was proposed that the 13mm offset can eliminate the spacer and also restore proper 'modulation'.

But now I know 13mm is not far enough to match the master fluid output to the Golf slave.
The pivot needs to be moved further inward (maybe 15mm? 16mm?), to eliminate the spacer.
But of course 13mm does improve modulation, widening the friction band by about 20%.

Anyone who does this "13mm" mod should STILL use the smallcar spacer to ABSOLUTELY limit the fluid output.

========

The slave release bearing is spring-loaded against the pressure-plate fingers.
It spins on the fingers full-time, which it can, because it's perfectly concentric.

One detail about this clutch/slave I've realized:
When the clutch components are ALL NEW, the slave extends farther rearward, more towards its 'stop'.
This is a CRITICAL limit, that we cannot see or ascertain.
When I visited Smallcar with a NEW install, they said they could "feel" my slave bumping against the stop.
I was being cocky and didn't use the spacer, because I thought 13mm mod was enough to match the master to the slave.
Which I asserted to Smallcar ..... and they were not convinced.
The (metal) slave blew shortly thereafter.

If 15mm, 16mm etc is sufficient so the nut does not touch the smallcar spacer, ONLY then can the spacer can be deleted.
But we don't know this snd nobody has tested it AFAIK.

As the clutch disc wears thinner, the slave moves away from the "far stop".
Its "when the clutch is new" and the diaphragm spring's fingers are 'farthest forward' that the limit is critical.

Got that?

It should be noted that with a "too thick" clutch disc, the pressure-plate fingers are more rearward, thus will position the start point of the slave "too far" and it may hit the stops when you press the clutch to the floor, even WITH the spacer.
The spacer absolutely limits the fluid output volume, but the spacer doesn't know the slave's 'starting point'.
The starting point is determined by the position of the pressure-plate fingers.
And if the disc is too thick, the pressure-plate fingers are 'farther rearward'
thus the slave's starting position is 'farther rearward' too,
and the slave may encounter the stops
with one full master "pump volume".

Smallcar owners should know that you cannot use a disc thicker than what smallcar specifies,
or it can blow the slave cylinder.
I don't know the disc max thickness, but it may be 'critical'.
Maybe Smallcar will provide it.

IMPORTANT NOTES

1) If you must install a thicker disc, you need to shim the pressure plate out the distance of the over-thickness.

2) You should never press the clutch HARD while there's no pressure-plate. Because the slave is spring-loaded, it's already against its max stops. The clutch pedal (in the van) would only go down a little because the slave is already against the far stop. Pressing the pedal hard will blow the slave apart. Don't press hard if bleeding.

3) You can replace the internal slave without fully "dropping" the trans. I did it by cradling the trans on ratchet straps. Here you can see the trans a few inches forward; far enough to get the slave over the input shaft. Possibly this method may be used to drop the trans to the ground, and perhaps to lift it off the ground too. I only moved the trans laterally in the cradle.
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'90 Westy EJ25, NEW oil rings (!) 2Peloquins, 3knobs, SyncroShop pressure-oiled pinion-bearing & GT mainshaft, filtered, cooled gearbox.
'87 Tintop w 47k 53k, '12 SmallCar EJ25, cooled filtered original gearbox
....KTMs, GasGas, SPOT mtb

[ALIKA T3]

The ratchet strap craddle works, I replaced my first transmission in the streets like that as I didn't have a floor jack. Whatever works!

I think I published a while back the dimensions of the slave cylinder at rest in the bellhousing in relation to the clutch diaphragm fingers/engine block
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Silicone Steering Boots and 930 Cv boots for sale in the classifieds.
Syncro transmission upgrade parts in the Classifieds.
Subaru EJ22+UN1 5 speed transmission
http://www.thesamba.com/vw/forum/viewtopic.php?t=416343
Syncro http://www.thesamba.com/vw/forum/viewtopic.php?t=4...num+gadget

[r39o]

When Fred S and I created our pedal mod it was because Small Car ignored the issue completely.

I forget exactly, but we weld on a new end using some tooling we made.

No spacer needed. Just the modded pedal.

We kind of stopped because people would infrequently return cores and we never could get enough fresh cores to justify the set up time.

But years later my clutch is still butter smooth. No blow outs. It just works. Smoother than stock VW too.

I basically forgot about this topic until I seen it here again.

I am happy.
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"Use the SEARCH, Luke" But first visit the Vanagon FAQ!

1990 Multivan EJ 22, Rancho trans 0.82 4th, Small Car front AC, CLKs w/ 215/65-16, homemade big brakes 303mm, Konis, Recaros, etc....

Click to see my ads for Cup holders, Subaru clutch fix and CLK wheels (no wheels currently)

[Sodo]

[daebir]

[Sodo]