Will Fiat coupe 16vt "viscodrive" box fit onto HF Turbo?

[Infectus-Guy]

Bit of a long shot, but i'm wondering if anyone has ever fitted or knows if a Fiat coupe 16vt "viscodrive" gearbox will fit onto a 1.6 Delta HF Turbo? The diff output bearings have given up and although i have a spare box i'd like to fit one with LSD. I've heard some of the Prismas were fitted with LSD but i don't think i'm going to have much luck tracking one of them down! This being the reason why i'd like to fit a readily available coupe box with "viscodrive". Not sure what i can do about the fact that my HFT has got a cable clutch, but if that's the only obstacle then i'm game.
Castle Combe in a FWD HF turbo with over 200bhp through the front wheels is a pretty scary place without LSD, and i really want to get ALL of the power down.
Thanks for any ideas,
Guy

[Guy Croft]

Well, the two blocks do have common M12 mounting points (4 off).

I think the Delta FW will accept the starter/bellhousing setup from the bigger engine, think they have common ring gear diameters and are set up in the same position axial position. The Delta has no balance shafts and will accept the starter (on the inlet side if it's reversed port 'ie' version head type). I have no idea where the started was fitted or whether the Delta 1.6 HF Turbo ie (if that's what it is) is common to the other engine.

As for shafts fitted along the side of the crankcase etc., no idea, sorry, but probably do-able.

Hope this helps some,

G

[Infectus-Guy]

Thanks for the ideas Guy, i might have found a more simple solution though! Its only the LSD i'm really after and having done a bit of homework i've found out that the funny looking black cylinder hanging off the side of the Fiat coupe turbo boxes is infact the Viscodrive LSD unit. I'm hoping that all of the parts required will unbolt from a coupe gearbox and that i will be able to fit them into my HF turbo box. I'll do some more homework and have a go, so will report back with any findings.
Guy

[Rik]

Please do let us know your findings on this one as I'm building a similar setup, I have the 2ltr Beta Block with a Thema Viscodrive box and everything marrys up just fine except for the driveshaft bearing housing on the back of the block, I simply can't find one that fits. although I've yet to try a 1.6 HF housing as I haven't tracked one down yet.

Rik

[Uros Piperski]

This box is actually a Delta integrale box with diferent differential cover and gearshift linkage. Inside is an open diff paired to the viscodrive coupler and you can't connect an ordinary diff to the viscodrive. That means you'll have to use both the differential and the viscodrive, plus the right-hand driveshaft because it has two splines on the diff/visco end (to connect it both to the diff and the viscodrive). With all those parts needed it's maybe better to use the whole gearbox and figure out the driveshafts and shift linkage. I'm using this box in my Dedra sw so I'll try to find some photos..

[Infectus-Guy]

Uros- Yes i realised i'd need the whole diff/viscodrive and driveshaft. My main concern with changing the whole box is that i'm not sure if all the gearbox to body mountings will line up. Shift mechanism looks like it would link up without too much trouble, but the other problem is that my HF turbo has a cable operated clutch so i'd have to convert to hydraulic. The slave cylinder end is easy, by the pedal/master cylinder end might cause problems.
Guy

[Uros Piperski]

The gearbox from the Dedra turbo that I installed in my Dedra sw is with a regular push type clutch. If you can get one of those, it's not too hard to convert it to cable operation. I have attached two photos where you can see my "mod". The cable lever is from my delta integrale gearbox (same spline) and I fabricated myself the cable "holder" (what is it called?). I got a custom cable made and everything is working fine for a few thousand kilometeres now.
Hope this helps a bit.

Uros

[Infectus-Guy]

That's brilliant thanks for the photos, i like what you've done there. I'm still not sure about the mounting points though, but when i start work on the delta i will offer it up next to my integrale box (same as coupe) and report back with my findings.
Guy

[Testament]

The Delta HF Turbo i.e. has the starter on the inlet side (next to the firewall) - I thought the coupe used a different gearbox though, similar to the larger croma/thema (integrale?) box - where the HF turbo uses a Tipo type gearbox. and then the six speed 20v gearbox may be different again?

No idea if the delta half shafts will fit to the 16vt gearbox if you were to fit the whole thing.

[SteveNZ]

Converting the gearbox just for the viscodrive seems silly. It's not a straight fit, its big and heavy and has much longer gear ratios. The car will be noticeably slower pulling through the gears.

I would suggest you buy a Quaife ATB diff. They have one off the shelf for the HF turbo i.e.

[Infectus-Guy]

Converting the gearbox just for the viscodrive seems silly. It's not a straight fit, its big and heavy and has much longer gear ratios. The car will be noticeably slower pulling through the gears.

I would suggest you buy a Quaife ATB diff. They have one off the shelf for the HF turbo i.e.

Thats all very well but i'm not willing to spend nearly £600 on a car that i bought for £200, the idea of the car is that it's a budget racer. I've got an Integrale evo for the "no expense spared" approach, which is why i've got to kerb my spending on the HFT. Having done the homework it looks like i'm on a raod to nowhere though, time to knock this idea on the head for the moment i think. Thanks for everyone's input.
Guy

[tmvolumex]

I was looking into this some years ago and I think you will find that the diff is actually locked and all the diff function is handled by the viscodrive. The diff is essentially locked because both stub shafts, inside the diff, connect to the ring gear. The swing axle connected to the viscodrive can slip relative the other side when turning etc. You should be able to swap the right side half shaft and the diff, keeping your ring gear and thus your existing final drive ratio.
Tom

[Infectus-Guy]

Thanks for the ideas Tom, I may well just have to settle for a "low ratio" 5 speed from an Uno or something similar.
thank you
Guy