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maual, to automatic
mattie182 - December 25th, 2002 at 01:14 PM

Hi, I have just inhertited a manual Superbug, not sure of the year.

i also got a auto gearbox, how hard is it to change,to the auto box, as I have no manual one?????

Are there any real probs????

Any information would be helpful


Matt

[Edited on 25-12-2002 by mattie182]


The_Bronze. - December 26th, 2002 at 12:46 AM

I would like to know this answer as well but for a 1300 standard 71. I'd like to power it up to tp1600 and would like to know if a stronger auto kombi box (or type 1) would be a good addition to beach / bush and road baja use.

Yes I know it would be slower - but I'm not in a hurry.


aussiebug - December 26th, 2002 at 06:00 AM

Here's a URL which explains the whole process of changing a xsemi-auto to a manual.

http://www.claydons.demon.co.uk/beetle/autostick/ 

If you are lucky, the tunnel may already have a clutch tube in it (some do, some don't). It's the only "hard" part of the operation.

I have a 68 semi-auto which a PO converted to manual (the clutch tube had to be installed). Works just fine, except that the clutch tube has been set forward just a few mm too far, so it's hard top get sufficient bend in the bowden tube (too many washers needed at the rear end of it).


aussiebug - December 26th, 2002 at 06:12 AM

Oh - and Bronze...there's no reason why you can't put a 1600 engine into the semi-auto - the US had lots of them. Just transfer the drive plate (the "flywheel";) from the 1300 engine to the 1600, plus the double oil pump for the back of the engine, and make sure your 1600 manifold has a vacuum point under the carby for the vacuum operated clutch.

The 1600 semi-auto uses the same 180mm clutch that all the semi-autos use, and this works OK because the torque converter takes most of the slip when you change gears - not the clutch plate.

The gearbox strength is no problem for the 1600, because the semi-auto gearbox is in fact the same as the manual box, but without 1st gear. The other ratios are the same as the manual - Low is the same as 2nd in a manual, D1 is 3rd and D2 is 4th.

The semi-auto gearbox usually has the 1200/1300 final drive ratios - 4.375:1, rather than the 4.125 or 3.875 of the manual 1500/1600s. This means that the semi-auto engine spins a little faster than the manual running at the same road speed, both because of the lower gearing and because the torque converter MUST have about 2 percent slip for it to work at all (the differential speed of the engine and gearbox sides make it work like a hydraulic pump and transfer power from engine to gearbox - if both were running at the same speed there would be no transference of torque from one to the other).

This results in a slightly lower top speed for the semi-autos compared to the same engine in a manual, and also to slightly higher fuel consumption.


11CAB - December 26th, 2002 at 06:49 AM

The beetles never came out with an automatic gearbox. The type 3 was the first with an automatic trans which is the same as the 003 kombi auto but with a different differential. The type 3 doesn't have frame horns like the beetle to interfere with so you will need some serious modifications to fit it between the horns. Also if you are going to use a type 1 engine you will need to get a type 3 flex plate which will bolt up ( the kombi one won't work on a beetle engine).
You will also need to get the type 3 linkages for the gearshift lever.
My advice would be to sell the auto and buy a manual which will fit straight in.
:thumb
Graham


The_Bronze. - December 27th, 2002 at 11:35 AM

Thanks Rob and Graham.

This is an interesting concept. Like engine thermodynamics it is another one that I am very interested in. I can't wait to get out of this place and into another where I can do some fiddling. Where we will be isn't that far from where i will be working so if things don't go back together so well or how I had planned then it's no hassle to use the wifes car or simple walk!

Cheers and happy new year to you all.


mattie182 - December 27th, 2002 at 12:38 PM

Thanks!!!!1