The easy gearbox solution for a Torero with a Rover V8 is to use a Renault 21/25 'UN1' Type unit. Parallel are able to supply a suitable bell-housing to mate this box to the Rover engine and also supply some special driveshaft flange adaptors to suit the Ford Granada driveshafts. The downside of the Renault 'box is that it isn't terribly strong. However, with the only real option being a Porsche unit at considerably more cost most builders will without doubt go for the Renault item. Even if a breakage is experienced, you could probably buy 10 Renault boxes for the price of one Porsche unit. Also, you would need to try and mate it to the Rover unit. There are probably bellhousings around to do this but I didn't look any further into it. Anyway, only an extremely hard driver with a very powerful V8 would experience continual Renault box problems.

Finding a new Renault 'box would be fairly difficult these days, and at the time of ordering my chassis Bill at Parallel pointed out that I should keep my eyes open for a secondhand one. About 7 weeks later Bill said one had been offered to him and did I want it. At the usual 250.00 I said yes and this is the unit I have now. It came complete with a clutch slave cylinder and even had clean gearbox oil in it which doesn't mean a lot but it's better than finding it full of dirt. It came with the Renault bellhousing which had to be removed for Parallel's custom Rover V8 type to be fitted. The only other preparation I did was to throughly clean and paint the box. After all, it had to look new to keep the registration guy happy... The pic below shows what you should be looking for- a tag at the very rear of the box, on the lowermost bolt with UN1 stamped into it. It's worth counting the crownwheel & pinion teeth as well (which can only be done with the bellhousing off) mine had a 9 tooth pinion with a 31 tooth crownwheel. 31 divided by 9 = 3.44 which means that mine is indeed a Renault 21 Turbo or Alpine Turbo/Alpine GTA. The tag on the back of the box shows '13' which means it has to be a Renault 21 Turbo. Below is some data found on the Renault transaxle gearbox range, which was kindly supplied by Andrew Williams (another Torero builder).

Model Part No. 1st 2nd 3rd 4th 5th Reverse Final
20 369.00 3.36 2.06 1.38 1.06 0.82 3.55 4.11
20 369.05 3.36 2.06 1.38 1.06 0.82 3.55 4.11
20TX 369 3.36 2.06 1.38 1.06 0.87 3.55 3.778
20LS/TS 369 3.82 2.18 1.41 1.03 0.86 3.55 3.778
21 Turbo UN1-13 3.36 2.05 1.38 1.03 0.82 3.54 3.44
25GTX UN1-03 3.36 2.05 1.38 1.04 0.82 3.55 3.89
25V6 UN1-04 3.36 2.05 1.38 0.96 0.76 3.55 3.89
Alpine GTA UN1-05 3.36 2.05 1.38 1.04 0.82 3.55 3.44
25 Blindee UN1-06 3.36 2.05 1.38 0.96 0.76 3.55 4.11
Alpine Turbo UN1-07 3.36 2.05 1.38 0.96 0.76 3.55 3.44
25V6 Turbo UN1-08 3.36 2.05 1.38 0.96 0.76 3.55 3.778
30TX 369-01/06/17 3.36 2.05 1.38 1.06 0.82 3.55 3.89
30TS 369-01/06/14 3.36 2.05 1.38 1.06 0.82 3.55 3.89


The Renault 21 Turbo is the preferred transaxle for use in the most replicas although the 25 Turbo and GTA boxes are also often used. Also note that if the GTA box is used it either has to be inverted or the differential reversed unless five reverse gears are required.
The selector shaft has to be modified to extend out of the right hand side of the gearbox so as to link up with the right hand gear change linkage.

A word of warning to those about to remove the Renault bellhousing to fit Parallels one.....empty the gearbox of oil first! I went blind into this and learnt the hard way. On the renault box the bellhousing also forms the front part of the gearbox and thus when I removed it I managed to dump the entire 75W contents on my nice freshly-cut lawn. I should have looked into it a bit further first but I have seen a large amount of gearboxes in my time and never have I seen a gearbox which uses the bellhousing as an integral part of it's design. Bloody French.

UN1 gearbox with no bellhousing UN1 gearbox with no bellhousing

FROM THIS......

........TO THIS!

 

So, once the bellhousing was off I gave the gearbox a good external clean with degreasant, being careful not to get any inside the now-exposed internals. Once clean and dry, I painted the casing with Hammerite (smooth) silver and to make it look really nice I replaced every nut, bolt and washer that holds the two halves together. I wouldn't have normally bothered with this but I needed to make the box look brand new for registration purposes, as you are only allowed one reconditioned component to get a new registration and that was going to be the engine. For the sake of a tin of Hammerite, a brush and some hardware totalling about 15 quid I think it's well worth doing. Finally, there is a deep horizontal hole at the rear of the gearbox which is originally used for the reverse lock on the Renault. You will need to block this with a gromment or bung as oil will drip from it otherwise.

 

DRIVESHAFT ADAPTORS & DRIVESHAFTS

Another part well worth buying is the ready-made adaptors from Parallel. These replace the Renault ones and enable you to use Ford Granada Mk2 2.8i driveshafts without any cutting/shortening/messing about of the shafts whatsoever, which is nice as the SVA doesn't allow it anyway. Fitting is fairly easy- drive out the spring pins that pass through the original Renault shafts to just leave you the multi-splined shaft sticking out of the box. Using a small file, carefully remove any sharp edges of metal from the Parallel adaptors where the holes have been drilled for the pins, and try sliding them on the gearbox splined shaft. NOTE: the adaptors will only line up one way with the holes in the gearbox shafts, so if they don't line up at first turn them through 180 degrees and try again. Once you are happy that they fit OK, remove them and wipe some 'Copperslip' or other anti-sieze agent onto the gearbox shafts. Slide the adaptors back on and once you are happy that the holes line up correctly tap in the spring pin with a drift. It takes a bit of care to get it started but once in they are fairly easy to tap through. Once fitted, pump some silicone sealant into one end of them until it comes out the other side. If you don't do this then a small amount of oil can work it's way out of the pins. Not a lot, but I hate oil leaks.

Once the adaptors are on, coat the edge of the supplied core plugs with silicon sealant and tap them into the centre of the adaptors. This will stop any gearbox oil from seeping down the splines and out of the adaptor. In reality you wouldn't get much anyway due to the tight interference fit but Parallel are quite thorough..... Also in the adaptor kit you should have 24 nice new allen cap head bolts to fit the driveshafts with.

The driveshafts themselves again came from Parallel which are fully reconditioned but look new so the registration man is kept happy. To be honest I'm not even sure if you can buy 'brand new' ones from Ford now. I decided to also buy 12 new 'banana' washers/plates each of which sit behind a pair of driveshaft bolts. I'm not sure what part they play but at 95p each I'm really not going to look too deep into it. For sure, 12 is far less worrying than some bolts coming loose and a driveshaft falling out.

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GEAR LINKAGE

When you buy the Parallel 'cable gearshift assembly' you also get the bracketry and levers needed to connect them to the Renault gearbox. This is somewhat handy. Some minor fitting work is required to fit the levers to the box such as drilling and tapping but it's no real drama. As with a lot of the Parallel-manufactured parts, the items are nicely produced and finished off with some powder-coating.


The locations of the linkage parts above were simply derived from putting the gearlever into the neutral position on the gearshift gate (mid-way between 3rd and 4th gear) and measuring the length of the cables from the nut adjusters (centralised on the thread) to the balljoints. I found that on my car the cable that comes round the back of the gearbox had a length of 22cm, and the side one was 19.5cm. I basically fitted the brackets and levers on the gearbox so that the distances were virtually the same (making sure the box was in neutral of course ;-)

Side cable fixed bracket: I found that I needed to pack out one of the mounts with a few washers as the 2 gearbox bolts it mounted to were not at the same level. It's possible that this is because the bracket has been fitted to the wrong pair of bolts but the two I picked were the only ones that would give me the correct 19.5cm distance. I must admit I'm not sure that my placement is correct, simply because of the spacing scenario, but I won't really be able to tell until the box is fitted. For sure though, theres no reason why the bracket can't be left where it is.

Side cable selection lever: This is the only piece that I have not fitted (you will see it held in place with mole grips in the aboves pics), simply because the location that I feel it should be in will require a hole to be drilled and tapped into the centre of the operating bar that goes into the gearbox. I don't want to do this until I am absolutely sure the placement is correct, so I will try and confirm with Parallel first. Will update with pics and text when done. UPDATE 13/10/03: I have now fitted the side lever after Naz visiting me and explaining where it should go. Pics above. There are two holes pre-drilled on the lever but I only used one of them as the other fell right in the middle of the operating shaft into the gearbox and I didn't fancy drilling it. So, I drilled another hole on the lever below it. It's certainly secure enough with two 8mm bolts. Note how close you need to get the lever to the rear bracket. Basically push the original lever back until it engages gear (I think it's 3rd) then affix the Parallel lever so that it's just off the big rear bracket.

Rear cable fixed bracket: Not really much you can go wrong with here. It's held on by two bolts, and you use the ones that are already in the gearbox. Just remove them, fit the bracket then bolt back in. You can't get it in the wrong place, or fit it upside down. Job done.

Rear cable selection lever: This is the one that requires the most work. The first thing you need to do is remove the original lever (it has two 6mm threads in it) which you do by removing the split pin from the centre of the shaft. Oddly, mine had a split pin inside another split pin which I've never seen before but it made no real difference. I drove out the smaller one first, then drove out the larger one. Make sure you buy the proper size drifts for this job as you can create a nightmare otherwise. Once done, the lever should freely spin on the shaft. Turn it through 180 degrees and temporarily affix it with anything that comes to hand (a matchstick poked in the hole may work) then find out what your cable distance is. Mine was 22cm as I said above. Measure the distance from the fixed bracket, whilst holding the moving lever in place with say mole grips and adjust the lever's position until the distance matches. Keeping the lever firmly clamped to the original Renault lever, take the lot off the shaft and drill the two 8mm holes through the Renault lever. While you're at it, also score along the edge of the Parallel lever onto the Renault lever. This is the material you will be cutting off to make a nice job, so that when finished the Renault lever follows the line of the Parallel one. You can see what I mean in the pictures above. When the Renault lever is painted black, the whole lot will look very neat and original.

Bolt the two levers together using 8mm nuts, bolts and washers (none are supplied in the kit so you'll have to go to a hardware store) then remove the molegrips and affix the lever back onto the shaft using the same two split pins that you removed earlier. They will be fine to use again providing you punched them out with the correct sized drift, Once all in place, check you have the correct distance to the fixed bracket and thats it. The only thing I will add is that the brackets could have been made so that the cable wasn't so offset (looking down from on top of the gearbox), but I think it will still work perfectly.

 

BELLHOUSING

The bellhousing fitment is made simple by Parallel. Their own casting, along with the comprehensive fitting kit which includes the actuating levers and even the slave cylinder mountings (for the UN1 cylinder) is about as pain-free as you can get (aside from the cost of course). The picture below shows the kit along with the 3-piece clutch kit, again specially supplied by Parallel to suit the combination of Rover V8 flywheel and Renault UN1 gearbox. Fit the bellhousing to the gearbox using a new paper gasket (part no. 7700565780), two new locating dowls (part no. 7705010123) and 2 new 'O' rings (part no. 7703065056) for the input shaft tube. I say 2 because the tube is initially slightly crushed when first bolted together when new so you need to make sure it's all snug again when you come to do it. Using 2 'O' rings ensures this. You could of course just buy a new input shaft tube but it's uneccessary. 2 'O' rings works just fine.

Whilst I was around the area and ordering some bits from Renault I also bought a new clutch slave cylinder dust cover for no other reason than to make it look new. It all helps at registration time if details like this look new.

The only gripe I have with the bellhousing 'kit' is that it doesn't come with new mounting bolts for the bellhousing to engine. The originals are too long, which is rather irritating when I ordered a brand new set thinking they would. So, you need to buy 6x 30mm and 2x 63mm long 3/8" UNC bolts. It would be nice to have a shank on all of them but I only managed to get that with the longer ones. I decided to buy cap-heads (allen-key type) rather than hex-heads as the clearance between the bolt head and surrounding bellhousing is pretty tight and I wasn't even sure if I was going to get a socket over them. Cap-heads are also high-tensile.

Bellhousing to engine bolts

 

CLUTCH ACTUATION

The clutch slave cylinder is the original Renault one, and bolts to the Parallel bellhousing with the two steel brackets supplied in the 'bellhousing kit' (they can be seen in the exploding view above right). There were no instructions for fitting the brackets and I didn't think they were the most self explanatory parts so I thought posting pics of the setup might help prospective builders. No other special work was needed- just s quick bleed of the fulid was necessary, which was actually very quick and easy. After that, I checked clutch operation and dis-engagement and all was fine. A nice setup actually, and certainly far neater than some of the bodged slave cylinder mountings I have seen on other kitcars.

clutchslave.jpg (77137 bytes) clutchslave2.jpg (77890 bytes) clutchslave3.jpg (74825 bytes)

 

FINAL FITMENT

A few pics of the installed setup. My guesstimate of the clearance required between the gearbox and the rear valance was actually over-conservative. I was paranoid that the box would hit so I spaced the valance out by quite a lot before fibreglassing it in place. I had previously fitted the box by itself to try and get an idea but without having it attached to the engine you can't be exactly sure where it will sit because you don't know what angle the box will be at. I guessed, and ended up with a 20mm gap. Well over considering you only really need 10mm but better that than getting a hoist, a friend to help and sorting out the logistics of everything only to find out that none of it will fit.

As for the linkages themselves, the bracketry for the gear cables was pretty much spot on. I did have a fairly major headache setting up the gearchange though- the problem is that the reverse on this box needs a longer travel than the other 5 foward gears. There is no provision for this in the Parallel linkage kit. It applies the same throw to ALL gears. Thus, I could set it up so that I could get reverse, but it then meant that the other gears were selecting halfway down the gate. If I set it up so the 5 foward gears were shifting just right, there wasn't enough travel to get reverse at all. The only proper answer would be to construct a fancy gear linkage that change the ratio of the throw only when selecting reverse. This would be some task, so my only option was to just elongate the gate on the reverse plane. Even then, I struggled to get enough throw. I also had to set up the cable so that my gearstick is slightly foward when in neutral, and I found I could also make the shift action better by swopping the cable balljoint from one side of the gearstick lug to the other. This meant that when the gearstick was pushed over to the left (as when selecting reverse) the cable itself wasn't forced into such an acute angle, and meant that all rearward action of the lever was translated directly to the cable, rather than sideways, as was happening originally when Parallel supplied it. Although the Parallel linkage id far bette rthan some other options I have seen, I think there is still room for improvement. If I hadn't spent a lot of extra time on my setup, it would be easy to build a car with a really nasty lever action, and to be selecting gears when the gearstick itself was nowhere near the ends of the gate.

One word of advice- make sure you have the reverse light connected and operational when checking reverse. It it easy to think that reverse has been selected but on checking the light you will find it hasn't. The light will ONLY illuminate when reverse has been properly selected.

As regard to the balljoints themselves, I would advise changing the plastic Parallel ones for metal. I found a broken one and it meant I spent a lot of unnecessary time trying to sort out excessive play. Even ones that were not broken had free movement in them so I bought 4 metal ones and replaced the lot. Not only will they wear better but I'll never have to worry about one breaking either.

For reference, all the pictures below were taken with the gearbox in the 'neutral' position.

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