Hey folks a few questions on gearboxes please.

My 63 Beetle that i am currently working on has the original 1200cc engine and gearbox.

My plans are to upgrade the engine to a 1641cc and would like to upgrade the gearbox accordingly, however reading deeper into this i have found out that there are a few things i need to consider.

• I need to source a 12v bellhousing case which is pre clearanced for a 200mm flywheel.

• I need to ensure that i use my current short axle shafts and tubes and not use long axle tubes to avoid the rear wheels sticking out past the wings.

I have also read that a freeway flyer gearbox is considered a good match for the 1641 engne.

My ask was, has anyone here done a similar upgrade or can anyone recommend a setup that works please as my knowledge on VW gearboxes is preety much zero.

Late 66 and 67 gearboxes were 6volt electrics but these were 12v size and fitting they were also wide 5 with the wider brake shoes but they were later longer shaft axles. Any 12v box after that will also fit with a change of shafts and perhaps a nose cone depending on the year as front mounts changed a few times. Post 72 boxes have a stronger clutch linkage and need a matching clutch cover.
Never had a freeway flier box but a 4.125 1500 or 1600 is fine, using smaller tyres than the buggy a 3.88 diff GT box would also do
To use your gearbox it is grinding the lugs off the bell housing inner where the bolts go through to clear the 12v flywheel and a 6v to 12v conversion bush for the starter motor.
Careful grinding gearboxes the dust can ignite and flash burn.

I run one on a stock 1600 reduces rev to just over 2000rpm @ 70 instead of 4000 on average consider it's an overdrive 4th 

Snoopy is correct.......   VW often used magnesium in the alloy mix when casting gearbox casings. The ground particles can be very hot. Anybody remember their first introduction to magnesium by the school physics/chemistry teacher ??  Out with a roll, strip to each pupil. Bunsen burner lit. Magnesium to flame and all but blinded. No safety glasses. No gloves. Just childish delight.   Those were days when "kids were kids" & teachers were"... well let me be nice and give a smile.      

If messing with gearboxes or tyre size combos, I wrote a quick spreadsheet that may help

https://www.beachbuggy.info/index.php/topic,7448.msg76863.html#msg76863

This spreadsheet is really useful thanks Dave....

Well im on the lookout for a good 1600 gearbox and a 1641cc or 1176cc engine for the beetle as there are no plans of sourcing top end new parts and getting a complete engine built, this time a good ready built one will suffice, not because its the wife's car but pockets arent as deep as they were for Ludicruz.

pockets arent as deep as they were

Know this feeling..... My state pension does not go far at all.