What are the differences in gear boxes ?

Just a quick question about gear boxes to enhance my limited knowledge.

Is there any main differences between gearboxes with the same engine sizes or same type of engine? I have seen on @paradox resto thread he has, I believe, a three ribbed gear box for his 1600 engine.
Mine is a five ribbed gear box for the same size engine. My van is a 1979 van, it originally had a T4 1900 engine, now it has a 1600tp. the PO swapped it over, do you think the engine was swapped by the PO but not the gearbox, if so what mods would they have had to have done to the gear box.

Is it just the external case is different or are the internals slightly different between the different type of gear boxes thinking gear ratios etc, I have read @Paul Weeding or @zed mentioning that there are different ones on other threads but not if there are differences.

Thanks for sharing the knowledge

 

You have a sought after gearbox. The input shafts sometimes need swapping and sometimes people chop a few mm off the end if they're going from long to short. I think you need a shorter one for your box with your engine.

 

The ribs offer greater strength so 5 is better than 3, 6 better than 5. My understanding is that >76 input shafts don't need to be changed. The boxes which come with type 4 engines had longer input shafts, I've just swapped boxes over and can concur that there is a difference of around 5mm between a 1600 'type 1' engined box and a 1700 'type 4' engined box.
There wasn't a stock type 4 style 1900 engine, I guess you mean 2000? If so it will also have a longer 4th

 

Thanks for that I was just being inquisitive, I hate not knowing the answers to small questions.

@Joker reply got me looking deeper. On the original V5c that was with the van it had it down as 1970cc capacity. I knew the engine in the van wasn't a type 4 engine and so got the paper work changed. The engine was a code CJ so it was a 2000cc.

 

CJ is actually 1971cc, so classed as a 2l

 

One final thing, does this mean then when I look at uprating the engine going down the type 4 route, can that be an option without to much fabrication, no need for a new gear box, gear box mount?

 

Check the code on your gearbox... it's on the lower left side on the midsection!! It's stamped in on a flat section just forward of the diff

mounts on the gearbox stay the same, but the engine has a different engine bar and chassis hangers