Pro Street Trans -70 or 71 and later?

[ryans88gt]

I am buying a new trans and clutch.

I see there is a cutoff at 1970 for the IRS transmissions.

I have a 1971 bug that was built in 1970.

Is the only difference the clutch throw out deal and is one preferable to the other?

If I am replacing both, does it matter which ones I get as long as they match each other?

I realize this is a kind of basic question so thanks for any help anyone can provide!

[Marc]

...If I am replacing both, does it matter which ones I get as long as they match each other?...

Yes, it does matter - the late setup is more robust and much more desirable IMO - and in mid`72 it was even improved further with the adoption of a larger-diameter/beefier cross-shaft (same as found on the `73-up single-sidecover transmissions such as the AT with 3.88 ring & pinion) for which a longer release lever is the norm. You can get longer levers for the early cross-shafts (or shorter ones for the late, for that matter) but the vast majority of the early ones are shorter, making for a stiffer pedal...harder on both your leg and the "hook" on the pedal cluster.

The arms on the cross-shaft are different, and the `71-up design requires a guide tube for the TOB to ride on - without it, the TOB would probably pop off before you made it around the block.

`70 cases have the three added bosses in the casting surrounding the input shaft seal, they just aren't drilled/tapped for guide tube hardware. There's also an aftermarket tube that plugs into the input seal bore - not as stout as the bolt-on type but it works if you need to convert a pre`70 trans to take the late TOB.

`71/early `72 cases will accept the pre`71 cross-shaft, so they can be back-dated to the early setup...although the only reason I can imagine for wanting to do that would be if you already owned an early cover that was balanced to your engine and couldn't be modified (see below)

So, if your present trans is the original `71 item it should have the small-diameter cross-shaft for the late-style TOB, with bolt-on guide tube. Since the TOB stays concentric with the cover throughout its range of travel, the thrust ring found on the center of the pre`71 covers is neither required or desired - and if you tried to use it with the guide tube in place it would almost certainly jam against it and damage it as you bolted in the engine.

Some covers, such as the Kennedy "Stage One/Two" etc. come with a thrust ring installed which can be removed, and the exposed "fingers" are short enough to clear the tube allowing them to be used with the late TOB...but there are other covers which have longer fingers so they can't be used this way (unless you grind them back).

[ryans88gt]

...If I am replacing both, does it matter which ones I get as long as they match each other?...

Yes, it does matter - the late setup is more robust and much more desirable IMO - and in mid`72 it was even improved further with the adoption of a larger-diameter/beefier cross-shaft (same as found on the `73-up single-sidecover transmissions such as the AT with 3.88 ring & pinion) for which a longer release lever is the norm. You can get longer levers for the early cross-shafts (or shorter ones for the late, for that matter) but the vast majority of the early ones are shorter, making for a stiffer pedal...harder on both your leg and the "hook" on the pedal cluster.

The arms on the cross-shaft are different, and the `71-up design requires a guide tube for the TOB to ride on - without it, the TOB would probably pop off before you made it around the block.

`70 cases have the three added bosses in the casting surrounding the input shaft seal, they just aren't drilled/tapped for guide tube hardware. There's also an aftermarket tube that plugs into the input seal bore - not as stout as the bolt-on type but it works if you need to convert a pre`70 trans to take the late TOB.

`71/early `72 cases will accept the pre`71 cross-shaft, so they can be back-dated to the early setup...although the only reason I can imagine for wanting to do that would be if you already owned an early cover that was balanced to your engine and couldn't be modified (see below)

So, if your present trans is the original `71 item it should have the small-diameter cross-shaft for the late-style TOB, with bolt-on guide tube. Since the TOB stays concentric with the cover throughout its range of travel, the thrust ring found on the center of the pre`71 covers is neither required or desired - and if you tried to use it with the guide tube in place it would almost certainly jam against it and damage it as you bolted in the engine.

Some covers, such as the Kennedy "Stage One/Two" etc. come with a thrust ring installed which can be removed, and the exposed "fingers" are short enough to clear the tube allowing them to be used with the late TOB...but there are other covers which have longer fingers so they can't be used this way (unless you grind them back).

OK thanks for the very detailed description. I am using the kennedy stage two. It has the ring, but can be removed. I am buying a pro street trans. So the ideal way to go is to get the 71-up design transmission and pop the ring off the pressure plate? The cross-shaft etc... 'should' transfer over if the trans in there is original. Did I get that right?

Thanks!

[Marc]

Yes.


The early-style (`61-`70) cross-shaft 113 141 701C, and the first-edition late style (`71/early`72) 113 141 701E are the same 16mm diameter and use the same bushings - they'll interchange in any trans case bushed for the 16mm shaft.

The second-edition late style (late`72-`79) 113 141 701F is 20mm in diameter so it won't fit in the earlier cases.

The E and the F both accept the 113 141 165B release bearing, for use against a clutch cover without the center thrust ring.

The "standard" release arm for the 16mm shafts is ~85mm center-to-center; you'll most likely want the longer ~100mm one from a Brazilian-market trans, especially if you'll be using a stout pressure plate. Bruce2 can probably fix you up if you can't find one.


While never offered from the factory (in the US market anyway, I dunno what might've been available overseas) there is a 20mm cross-shaft available that accepts the early 111/113 141 165A release bearing. Hard to imagine a scenario where you'd want one, but they're out there.



viewtopic.php?f=50&t=104581

[Henryhoehandle]

Never saw a 20mm shaft that used the early bearing..weird. i don't know why anyone would want one either. Nothing about a vw transmission surprises me anymore lol

[Bruce2]

While I was at KCR once, I spied a 5 gal bucket full of 71-72 Type 1 cross shafts. When I asked, he said they were take-offs. Most of his off-road customers prefer the early floppy TO bearing, so they request he downgrade their 71 and 72 gearboxes.
That's why a 20mm early TO bearing cross shaft exist, people demand it.
So many stupid people out there.

[Marc]

My son bought a `67 Beetle a few years back which came with a rebuilt transaxle (not sure who it was from but I suspect Rancho). They had used a late DSC case and fitted it with an early-style 20mm cross-shaft, probably to make it "correct" for a `67. Cadmium-plated P.O.S. part, probably had less than 10,000mi on it and the cradles in the arms were already worn badly.

[Henryhoehandle]

I routinely make cv flanges for the type 1 so a type 2 joint can be used, but I have also had people wanting to put type 1 cv joints onto a type 2 bus transmission. When I asked why they want to do that, they say that the type 1 joint is stronger.....

[Bruce2]

Back in the 80s there were a few guys changing Beetle axles to Datsun 510 axles with U-joints, because they said they are stronger.
I once worked with a guy who was into 510s and he said the hot ticket was to convert their 510s to Beetle axles because CVs are better than U-joints.