Hi chaps, i wonder if anyone has, or knows of anyone who has experience with swapping gears between various fiat/alfa boxes. The reason i ask is that i want to build up a box for my FWD lancia delta hf turbo hillclimb car with a tall first gear then try and bunch up the rest (2nd, 3rd, 4th, not to worried about 5th) using swapped over gear sets. I can't afford to have a custom box made up so this is my only real option, i'd like to use a coupe box with the visco drive if possible, better than no slipper at all. So i guess this will be the box i will start with, then I'm hoping if there are enough final drive options out there i might be able to get something sorted.
Anyone think this is possible of have i had one lungful of waxoyl smoke too many?
Thanks,
Guy

No idea on the gearbox front, but if you want the viscousdrive, you will definitely need a 16vt gearbox, then if you can get hold of a tipo 16v gearbox, this will give you a more shorter gear ratio. They are both hydraulic in operation, but the tipo is a pull clutch and the coupe a push.

As for swapping the cogs over, can't help I'm afraid

Coupe is a pull clutch.

you can use the final drive from various alfas to shorten the gears considerably, i have a final drive from an alfa in mine along with the main shaft from a lancia thesis although you wouldn't need the latter, significantly improves acceleration

http://www.fiatcoupeclub.org/forum/ubbthreads.php?ubb=showflat&Main=70800&Number=859856#Post859856

http://www.fiatcoupeclub.org/forum/ubbthreads.php?ubb=showflat&Main=86943&Number=1094010#Post1094010

above are a couple of posts which would be worth a read

So it is, the tipo is a push clutch then

Are you sure about Tipo? Out of my knowledge base that one, but I thought it was hydraulic operation which probably means pull type.

Def a push, as when I converted my tipo to a 16vt engine, I kept my old tipo gearbox, but couldn't use the tipo clutch and had to revert to a 'grale 8v clutch by keeping the push action

So old Tipo is cable? And you weren't able to use your Tipo clutch in your Tipo 'box (which sounds strange because....?

It wasn't strong enough presumably?

I believe the HF box is derived from the Beta box as are the Croma and Tipo (non 16V) boxes. The 5 speed Coupe Turbo boxes are derived from the Thema Turbo type box as are the 5 speed Alfa V6 boxes. 6 speed boxes from later Alfas are again a derivation of the earlier 5 speed boxes, but as far as I know, no parts are compatible with the 5 speed boxes. Alfa 2 litre front wheel drive gearboxes may be of the same type at the HF/Beta/Tipo/Croma as they are definitely not the same type as used on the V6 engines - so worth speaking to an Alfa garage/expert maybe.

For an LSD, one that fits a Beta-type diff would be required.

As far as I know, in all the boxes, first and second gears are machined onto the main and output shafts, so you need to swap the pair. The final drive pinion is also machined onto the output, so the correct mainshaft, output shaft and final drive ring gear all have to come from the same box, otherwise the gears won't mesh properly = broken gearbox.

I have details of the production ratios for the Thema/Alfa V6 type boxes, but not the Beta/Croma/Tipo so can't offer you any guidance.

The choice of first/second gear "pairs" in the Thema derived boxes is limited to only four:

3.5:1 first with a 2.235:1 second
3.5:1 first with a 2.176:1 second
3.75:1 first with a 2.176:1 second
3.75:1 first with a 2.235:1 second

Pretty hopeless really!

No, the tipo 16v (i don't know about the lesser models) had a hydraulic push clutch. When I converted to 16vt, I decided to keep my tipo gearbox and hydraulic, so used an 8v 'grale clutch and cover as this would take the torque and allowed me to keep my push style hydraulic clutch

At the time the Delta HF was advertised as having a ZF box

Gearsets from Alfa 6 speed box are interchangeable with the Fiat Coupe 6 speed box (and those of Lancia Thesis)

Gearboxman might know - www.gearboxman.co.uk

Tipo is a hydraulic fork push clutch.

Not quite right.

There are 2 series of gearbox for the FWD cars of the era. That which evolved from the Fiat 128 box. These were used in X19s Unos and upgraded for the early versions of, 130TC and HF turbo carb. This gearbox then went through annother evolution for the Tipo. A lot of other cars ended up sharing this Tipo derived gearbox, including HF turbo i.e., Uno turbo, Alfa twin spark 147, 156, Punto GT, Coupe NA. These gearboxes have a Quaife ATB avaiable off the shelf and it can be adapted to fit the pre Tipo 128 boxes. The ATB still fits the cases it however needs the crownwheel adapted to fit

The other series is that of the Beta which evolved into the the gearbox that was used in Cromas, Themas, Integrale, Coupe turbo 5 speed. Alfa V6.

For the original poster, the 128 and Tipo gearsets are all somewhat interchaneable. If you can find a set of gears that you like you maybe able to make it work. But I dont think you will find exactly what you want by mixing ratios like this.

Edit, just had a thought, if this is a Delta 2 HF turbo 16V, it has the Coupe turbo box, not Tipo of the old HF turbos.

It's a Delta 1.6 turbo that he has

Thanks for the ideas everyone, you guys sure know your stuff! Group5 - Well i didn't know that! I assumed you could split all the gears but if 1st and 2nd are machine out of one billet i probably won't have much luck! Maybe i could build box with an unusably short 1st and a usable long 2nd. Bit of a waste of a gear but on a hill climb it won't matter.
Guy

Gears are not machined on the shafts in the tipo 16v box.

Oooo thats good to know! Does the tipo 16v box have the visco drive? What have you done with your box Rich, have you switched gears around at all or are the standard ratios okay for the track?
Guy

I'm 99% certain the Tipo 16V doesn't have the Viscodrive, I'd have remembered from when it won a CAR Magazine Giant Test back in the day and they'd have mentioned it when that white one was PH's SOTW a few months ago.

It doesn't have a viscodrive.

another person worth speaking to is dave at rusper alfa, he built the box on mine and advised what gears would fit

Mine has all the gears changed for a Bacci synchro kit, bacci final drive, and bacci plate diff. The quaife is a slightly cheaper option. I had a 4.0:1 then changed to 4.2:1 FD had to increase the RPM for sliverstone, in hindsight I think I would have kept the 4:1.

My fist box was std gears but with a 3.9:1 FD from an alfa 1.4 tspark it was actually pretty good, with a quaife I would have been happy. Neil Smith at NJS alfa in Pershore worcs built it (a few times!!)

Big thanks again to everyone for sharing their knowledge, saves me a lot of time and may help me end up with a better box. I'll try Dave and Neil.
Thanks again,
Guy