How to make the 5 th gear longer ?is there some other gearbox that has longear gears?

Maybe some TD 2,5 fiat/alfa or something simillar ,,, but it is only idea without any confirmation

some ideas_?

I think the 8 valve Lancia Thema IE Turbo had the tallest gearing with a final drive of 2.944:1.

Fit a 20VT 6 speed box?

Ideas .. http://www.bacciromano.com/index.php?p=prodotti&l=eng&cat1=24&cat2=37&mar=4

Huh...$$$, what should be expected indeed...

yhm $$$ but you can see what are you looking for...

True...remember, few years ago, been asked 600E for one only in/out-toothed ring for daimler-steyr gearbox. And it seems the possibility to source exactly matching parts from other fiat-alfa-lancia car tends to zero.

the best thing is to fit the 6 speed but it isn possible...are there some lancia alfa,fiat parts to combine?

Not so great approval the 6 speeder though...imo

You can fit a 6 speed to a 16v, but there is a lot of work involved.

what kind of modifications?

Hubs, brakes, drive shaft, visco and wheels

i think that the flywheel is diferent or?

this will help

The 16v starter motor does fit, but needs to be ground down.
You will need to drill out one of the main fixing points on the engine.
As for the driveshafts, i never did figure out what would be needed, as i gave up with fitting it.

so i need a 20 vt flywheel and a clutch+driveshafts,gearlinkage,?why i ask about the flywheel because here in italy they tell me that its not possible because of the diferent flywheel teth...if i do it i will be the first in italy to mount the 6 speed..whats the rpm in 6th gear on highway at about 70/80 miles?

No, you keep the 16v flywheel, else the starter motor teeth wont line up on the flywheel

ok thanks 4 the info> are these good to replace the 5th gear >36/33 turbo /primary drive >11/39
35/32 turbo
37/33 aspirated
39/34 aspirated

CROMA> Tipo>
32/28
37/33
39/34
46/35 38/31
39/30 39/34
39/30 52/43
38/29 34/27
47/34 39/31
43/31
36/33
35/32
43/35
30/37


what would be the best ?

can someone post the gear ratios of the original gears and final drive cant find them...i think i would put a thema 5 th gear diesel if its possible..are the gearboxes similar or?i intend just to swap the 2 5th gear teeth

You can check it in eper for example :-)

if you download the following programme it will allow you to put in the different gear ratios so you can see what difference altering the gearing will make
http://www.locost7.info/gearcalc.php

already have the program.calculating around ...i have been on eper only can se the thema t.d. ratios..cant see the alfa ratios..and calculating the original final drive off t16 from eper is wrong..just need to know are the gearboxes similar from alfa ,lancia?

its seems that the gears would go just fine in these ratios >tipo td,thema td,multipla td,bravo/brava td,croma td,,if someone knows if these gearboxes are similar,,??i think the 5th gear can be changed by just taking of the wheel and the gearbox cap that has the 5 th on the external side..someone?dont wanna pay 500 euros for the bacci-romano gears

Petrol Thema is definitely similar/same box. I believe the Croma and Tipo are not similar (more similar to the Beta box) and so I don't think you can swap components between the two types.

I don't know anything about the diesel gearboxes and their compatibility though.

heard from a friend here..he swaped from a multipla td but made a swap in a coupe aspirated 1.8..doubt we have the same gearboxes?

...if somebody have a disassembled gearbox and could take accurate measurements of the mentioned gear, would be some starting point...

A diesel Thema/Croma has the longest final gear I believe. I used it on my friend's Thema 2000, he has smth like 150kmh at 3000 rpm on 5th.

thanks,so you have changed just the 5 th gear not the final drive...?

be careful you don't use to long a gear, something like the above would be 31mph per 1000rpm giving a jump of over 10mph per 1000rpm from 4th to 5th

to be honest i think the coupe would struggle to pull much over 28mph per 1000rpm as a gear ratio

think of your torque curve before you go for to long a gear