Vitesse/Mazda 5-speed gearbox

Earth Strap

July 17th: After a couple of weeks of pondering I arrange a test-drive of the Vitesse engineer's roadster V8 conversion travelling there in Vee to get a back to back comparison - carefully! A very different driving experience in the car as a whole with large capacity Rover engine, fuel injected, modified suspension and what felt like power steering - took a bit of getting used to, and unsurprisingly the gearbox itself is very different as well. Very light changes - finger-tip from 3rd to 4th for example, but with a positive detent action confirming it was in gear. I was looking forward to no longer having the baulking trying to select 1st or reverse from a standstill ... until I read an MX5 5-speed page with people saying they get baulking in reverse! We shall see. I did make a comment on the test drive that I have never had a gearbox yet where it never happened, and the chap with me didn't comment. (November 24: So far I think it has baulked once in 1st and definitely has once in reverse in less than 1000 miles). Many comments about 'ideal ratios', it's never been a issue with the torque of the V8 unlike the roadster where pulling away uphill you need more revs in 1st and 2nd before changing up as there is quite a big gap compared to between 3rd and 4th (some 57% as opposed to 38% for the 4-cylinder with 58% and 26% for the factory V8). Reverse is in the same fore and aft plane as fifth (but with an interlock to prevent you going direct from 5th to reverse without going across the the left in neutral first) where ideally it would have been 4th and 5th and reverse with a 'dog-leg' first. The biggest risk is that it's of course possible to go from 3rd to reverse if you happen to put a bit of sideways pressure on the lever (which I have managed to do once) when aiming for 4th. But you can't have everything, so I've decided to go with it - The pre-sales information and support from Vitesse has been faultless. I know I'll miss the overdrive as it is just so good to flick the column stalk for overtaking, but it's either go with the 5-speed or sell the car with a suspect gearbox. Installation to start in just under three weeks, should take one week. I'll have all the 'old bits' back and take a view on what to with them later on. Good factory V8 boxes can fetch up to £1k, I may decide to keep it with the car as I have done with the original block for the next custodian. I may have a look at what might be wrong myself, I'm unlikely to pay out more money to have it 'fixed' yet again when I'm not going to use it. (I did, and found and fixed the problem), and subsequently sold the whole kit from clutch to prop-shaft plus cross-member to someone wanting to reverse an LT77 conversion at a fair price, so we were both happy.

August 5th: I deliver Vee to Vitesse at Hinckley and get two trains and a bus back home, expected completion one week. However I get a phone call on the Wednesday asking if it would be possible to delay it by a couple of days as they are having problems installing fuel injection on the previous job. Obviously I'm keen to get the car back, but I know it's not a good idea to park a job for something else half-way through then have to go back to it, and we are in the main holiday period with some staff away, so I agree as I don't want them rushing my job either. In the meantime I've sent the speedo off to Speedograph Richfield (recommended by Vitesse) for recalibration, and to clean it up after the faulty speedo drive pinion oil seal from the OD refurbish had leaked, contaminated the speedo and left the ODO wheels mucky. The initial estimate of £180 (recalibration only via Vitesse £65) was to include changing the wheels so I sent it off complete with correspondence and got a firm quote back of £125, I put the lower cost down to the fact that the speedo was otherwise sound and functioning correctly.

Two weeks later it comes back - and the odo wheels (with the possible exception of the 10k) are still mucky! Not best pleased. Email them and get an apologetic letter back saying if I send it back to them they will replace them - which means another £10 postage and another two or three week wait, by which time I should have the car back and be wanting to drive it - without a speedo! I could leave it, but before all this I was aware of the mucky wheels every time I looked at the mileage so will send it back ... after checking that it has actually been recalibrated! Expecting a gap between car and speedo return at the outset I've put a speedo app on my phone so can use that. I hope this isn't a sign that I should have cut my losses and sold it.

More gloom when I get an email with photos showing both inlet manifolds cracked between the front and rear pairs, and oil pooling on top of the inlet manifold gasket. They offered to take the manifolds to a local TIG welder but couldn't give me an idea of price or timescales, and as they hadn't been blowing I declined - maybe a foolish decision:

They also offered to replace the gasket for about £80 without delaying the job. Ordinarily I would have accepted that but I know the front offside thread is weak and won't fully torque up, and I didn't want more issues to come to light with taking the manifold off, so declined that as well. I've done both jobs myself in the past so can do them again, and will helicoil the head thread first, maybe over winter.

August 15th: Vee ready with her new 5-speed box on the Tuesday, but easier for me to collect on the Thursday. Reversed the journey by bus and trains and a half-hour walk to Vitesse rather than asking them to pick me up although they did offer. Couldn't see Vee walking in through the gates until I got past a delivery van to see her suddenly come into view gleaming and resplendent because they had washed her - attention to detail. Had a bit of a chat with Wendy in the office then her and Christian down at the car. He said despite their best efforts the near-side manifold was now blowing, disturbing the manifold has unsurprisingly opened up the crack. One of the things that surprised me was that they remove the engine first and then the gearbox (as I did at home) as the two together are so unwieldy, despite having a lift and a large engine hoist in the workshop. That was a huge job just to get at the top two bell-housing bolts, but ironically the Vitesse bell-housing has a significantly thinner flange and the bolts are much more accessible for installation at least!

Another comment was that he recommended installing an earth strap between the block and the chassis rail somewhere as the original is removed along with the removable crossmember. I expressed surprise asking how the engine got an earth at the moment, as they had road-tested it after installation and I had started it up, and he said 'other paths'. I know they recommend fitting one in the self-install instructions and thought they would have done so as part of the turnkey operation, so that will be something to look at.

Then to get the old box into the back of Vee! Discussing it on my test-drive visit Wendy said they could put it in the box the Mazda gearbox comes in so that gives me a size and we measure one up minus it's feet which are several inches high - 100cm long x 44 high and 47 wide. Back home I make a 44 x 47 template and that will just go through the open hatch, and most of the way to the front with the seat tilted forward, and 100 long fits easily with several inches clearance to the roof at the front. In hindsight I should have taken the wheel cover carpet and rear seat back out, as with those in and cloths on them to protect against any oil but they had drained it at my request and put it in a poly bag so with that and being in a very stout cardboard box there would be little chance. As it was it only just went in with me pushing the rear cant rail up out of the way while two of them (not Wendy!) pushed and pulled, and it was in!

A bit of good news concerns the speedo cable. I'd previously asked about the length as the original 57" had to be removed and attached groping behind the dash, but the later 60" allows it to be pulled forwards. Asking about that earlier they just mentioned reaching behind the dash to attach, but in fact it projects forwards about as far as the 60" so it can be attached from the front. They had also put a cable-tie round the cable to stop the knurled wheel sliding down into the spaghetti behind the dash - more attention to detail:

And then the journey home! First stop a petrol station as I'd only been putting minimal fuel in while all this was going on, and a chap came up and said "You don't see one for years and then two appear within ten minutes!" Wendy had mentioned a black one was just about to leave but I was upstairs in the office and didn't see it. He had a 4-cylinder so a bit of a chat ensued, then after I had put a couple of gallons in an old chap doing a bit of cleaning up round the pumps also wanted a chat. Then I could get away. Got on the M69 and went for OD ... but of course I don't have OD any more, so select 5th instead. That started me thinking about 5th and reverse being in the same plane. The old box is biased to the 1/2 plane so you have to move it across to the right against spring pressure for 3rd and 4th. This box is biased to the 3/4 plane and there is spring pressure to move it to the right for 5th and reverse. I will have to be very careful not to knock it out of gear in 4th or 5th, and while rolling along move it to the right and pull it back for 4th as I would have done with the old box ... because that will be reverse! Very careful, as of course I can still do that in Bee without causing a problem. That's probably the biggest short-coming with this box i.e. no 'lift' or detent in order to select reverse. The quid pro quo is that you can't hit reverse when doing a rapid down-change from 3rd to 2nd and going through the reverse detent as you can with the original boxes. On that subject reverse seems to have a shorter 'throw' than forward gears, so at first I think it has baulked and not gone in and needed a tentative lift of the clutch to confirm, but it has gone in.

Sounds and feels different although at the moment the near-side exhaust manifold is blowing - the disturbance of removal and replacement having opened up the crack (or not, it's blowing badly from one of the flanges), I'll get that sorted sooner rather than later and it is the easier one of the two to get off. There does seem more mechanical noise when driving - even idling there is a sound like the cooling fans running although quieter. This may be down to the gearbox mounting being different, but could also be the flexible pipe down from the master cylinder to the slave cylinder inside the bell-housing and the bleed pipe coming back up resting against the body. In both Bee and Vee there was always slightly more mechanical noise when in OD which I put down to the additional epicyclic gearing, this makes a similar but quieter noise in all gears which I wasn't expecting. On further thought the MX5 probably has more sound-deadening! I also seem to be able to feel a draught on the palm of my hand while it is resting on the knob which puzzled me. Going into gears there seems to be 'detent' noise and feel which the original didn't have, but then that could be quite heavy (especially sometimes in Bee going between 3rd and 4th which has always been there) whereas this is very light in all the gears. With varying speeds on the M6 and M42 coming home I found I was leaving it in 5th, which the engine pulled perfectly happily, whereas I would normally have flicked OD out and back in as required, so something to get used to, I will miss that.

Back home and looking around under the bonnet I realised the prop had been refitted the wrong way round with the release lever at the back, so I corrected that.

Also noticed that the front rack mounting bolts had been fitted upside down (the rack has to come off to remove the engine as the exhaust manifold that side fouls it), the bolts should be fitted from the bottom as there is a section of weld inside the bracket to hold the bolt while the nut is tightened from above. They had also changed the front bolts, and fitted Nylocs underneath, with lock-washers which is odd.

Then looking round inside I could see the edge of the leather gear lever gaiter sticking out from under the chrome trim ring. Took the ring off (noticing they had the short screw at the side instead of the front and it hadn't picked up the threads) and realised they had unstapled the leather gaiter from the rubber gaiter. I had previously reversed and restapled it to prevent the rubber gaiter from pulling on the lever which was opening the gearbox switch and turning OD off, the V8 having OD in 4th gear only it only closes when the lever is pulled down into 4th as well as across. It's operation is marginal compared to the 4-cylinder where you only have to pull the lever across to the 3/4 plane to close the switch, and after 230k miles the mechanism was probably as worn as everything else. I restapled it back as it would have been originally and refitted the ring with the screws in the right places. With the gaiter off I can see the gearbox through the hole in the tunnel is noticeably offset towards the driver - but actually it is the hole that is offset towards the passenger if you line it up with the arm-rest cubby, the gearbox itself is central. Bee is almost central to the hole, Vee originally was a small amount towards the driver presumably from the original remote housing. But the Mazda gearbox socket is central to the car so the lever has a very definite double-bend to come up through the middle of the gaiter:

The gear-knob had to come off for that, it has a 9/16" lock-nut underneath. I had already done that because since a visit to the Land Rover factory some years ago where they gave me rubber 'sleeves' with Jaguar and Land Rover logos to cover my engagement and wedding rings, and I had put them on the lever afterwards as a keep-sake. I noticed they were missing when I picked up the car, but found them in a poly bag (one of several) with the old gear lever bits and pieces. My gear knob is missing though which was an original for which I had to pay quite a bit to replace an after-market one. This gear knob seemed higher than I remembered and measuring from the console up to a spirit-level on the knob on both Bee and Vee it is 1cm higher. I did screw it down as far as it would go before tightening the lock-nut, but there are plenty of unused threads (3/8" UNC) on the lever (clearly visible from the driving seat and to the touch), it took 10 turns to 'bottom' on the lever so I'll cut about 1/2" off.

After a 20-miler Sunday morning to get the paper a very early impression is that it's changed the character of the car. I remember years ago at a V8 event being asked if I wanted a 5-speed and I replied with a smile "Not while I can have a standard box with OD". Having now been forced into getting one that view has been reinforced. If it has a dodgy gearbox then the first choice should always be repair or replacement with the same - for me not an option with this having already had two rebuilds the last one less than 5k ago and a different box being an unknown quantity. Not being able to flick it in and out of OD with the column stalk is a huge loss, but what choice did I have? If I'd sold the car with a dodgy gearbox (at a considerable discount to its true worth) I would always have wondered what a conversion would have been like, at least now I know.

Subsequently I realise that the lever is noticeably thinner than the original at 0.375" as opposed to 0.447", so whereas before the top of the rubber gaiter was a snug fit to the lever there is a gap to the new one, and the noise is probably coming up through that gap ... and so is the draught I can feel! Pondering options I consider wrapping tape round to build it up with a bit of heat-shrink to stop it unravelling, then hit on the idea of a short length of hose. I have off-cuts of 1/4" and 5/16" but it needs 3/8" which I don't have, and that would only butt up against the top of the gaiter so may leave gaps or move around in different gears. Or successive layers of heat-shrink to build the thickness up to about .447" and fit inside the top of the gaiter like the original shaft - but I don't have any big enough. So I opt for layers of insulating tape and keep wrapping them round - the top of the rubber gaiter is less than half the height of the leather outer - until I can feel the resistance of the rubber gaiter going over them in trial fits. No heat-shrink for an outer layer to resist the tape unravelling, but as it's inside the neck of the rubber gaiter that should keep it in place. If not I'll get a piece of suitably-sized heat-shrink. Note the length of the thread:

I wrap some cloth round the gear lever, pushing it down through the hole in the centre console, and spread it out to catch metal bits while I shorten the lever with a hack-saw. But first I spin a 3/8" UNC die on to clean up the thread after it has been cut. Thankfully not hardened steel, I cut through in a few minutes.

Remove the die, drop the gaiters over and push the neck of the rubber one down over the tape, pop my JLR finger-ring protectors on, then the lock-nut to the bottom of the threads, then the knob which goes all the way down to meet the lock-nut, which I tighten up to the underside of the knob. The threads are now completely covered by the knob and any remaining bare shaft is covered by the finger-ring protectors - much better aesthetically, it remains to be seen what it has done to the noise and draught:

And the answer is that it has stopped both the noise and the draught, which I'm pleased about. After a 37-mile jolly on a sunny morning that involved inadvertently getting tangled up in Redditch suburbs which at least gave me the 'opportunity' to use the gearbox much more that it otherwise would have done, and once in gear either it is now the same as the old box or I'm getting used to it. Or both. Changing gear the lever still seems to have a closer physical relationship to the mechanicals - the original lever seemed 'damped' by comparison, But the lightness and (so far) no baulking is good. One thing I'm noticing is that with the original boxes I rarely put the clutch to the floor to change gear but now I find myself doing so as otherwise there is more of a sensation though the knob.

I enquired about the original gear knob and they said it had been put in the footwell - where I found it, ironically appearing in the above photos but not noticed!

Coming back from another trip over our multitude of traffic calming measures there was a dull thump that sounded like something big was hitting body-work, also mentioned on the V8 Register account, that turned out to be to do with the engine steady bar. I noticed that the engine mount location plates had not been refitted to the underside of the chassis brackets for some reason, so possibly something to do with it. Then when looking at the nearside exhaust manifold thinking ahead to getting it off I realised the third branch was practically touching my heat insulation on the inner wing, whereas the other side there was getting on for a 1/2" gap! Then looking at the air-box it did seem to be tilted down to the right, and a spirit level showed it was half a bubble down that side. Also having an engine steady bar the easiest thing (pending looking at the engine mounts) was to adjust that, and it did seem to be pulling the engine practically all the way to the nearside. So I slacken the Nyloc nut on the inboard side of the head bracket many turns. I try turning the outer plain nut but it is locked to the inner nut, and I don't have a 3/4" spanner thin enough to hold that one while I turn the outer. Both plus the bar are turning together, so I have to grip the bar with Stilsons and that does allow me to turn both nuts to push the top of the engine towards the offside. I keep going until the spirit level bubble has moved to the other side, and it has opened up a bit of a gap between the manifold and the inner wing, but not much. Looking at the mounts the near-side is definitely lower on the chassis bracket than the offside so I'll see about refitting the location plates.

Three weeks after sending the speedo back to Speedograph I have heard nothing - not even confirmation of receipt as asked - so phone to be told "We were waiting for the orange wheels, they have come in today so I will be assembling it and it will go out in the post first thing tomorrow". Firstly I have no confidence that I'm being told the truth when you chase someone and they say it 'arrived today', and why aren't things collected by the Post Office at the end of the day instead of first thing in the morning? Three days later still nothing so I'll be making another phone call this afternoon and asking for tracking information. However I had no delivery info for the first time it came back, so I'm not hopeful. Clive Wheatley said 'not to bother' getting it recalibrated! Oh well, too late now. Call again to be told about some problem or other, should have gone out last night but didn't, will send it Special Delivery today and I should get it tomorrow morning! We shall see ...

And wonder of wonders it arrives with nice clean wheels. Another £54 to pay which I wasn't surprised at as the formal quote was less than the estimate at initial enquiry. After only a brief trip out at no more that 35mph it seems to be over-reading by the legal maximum of 10% compared with my smart phone speedo app. Irritating, previously (and Bee) it was only 1% or 2% over at most speeds. Needs a longer/faster run to be sure, and see what the mileage is doing. Over several runs the mileage is pretty-well spot on, but the speed is consistently 10% if not 11% over. This is governed by the hair-spring in the pointer, which I'm not going to be able to do much about, but at the lower speeds I might be able to 'correct' it by resetting the pointer on the spindle, which does the trick.

Still, it's nice to get Vee back together again (mileage tweaked to add on what we had done without a speedo):

Earth strap: After a few weeks I decide to check the voltage between the engine and the body while cranking - which shows the amount of voltage being lost in that connection, to find it was about 1.3v i.e. less than 9v with a good battery instead of close to 10v so definitely worth doing something about. How it's earthing now I don't know as the factory engine and gearbox mounts completely isolate it which means if the factory earth connection fails it can only earth through things like throttle, choke and heater cables plus possibly temp gauge capillary and speedo cable, which get hot if not smoke, as well as giving slow cranking. I've also read about someone with a braided clutch hose that exploded while cranking because it was carrying the majority of the current. Whilst cranking seemed 'normal' when I first got the car back the last couple of times on cold starts it has seemed a bit slower than normal, which was why I checked it.

Vitesse mentioned the now unused clutch hose bracket on the chassis rail and a bolt on the engine can be used for the earth strap, and the most sensible place for the latter seems to be the lower starter bolt. The starter has a pretty big bolt with a 3/8" thread (the hole in the earth strap terminals I had bought 5/16") so second choice would be where the flywheel cover is screwed to the gearbox casing. Both those are about 20cm from the chassis bracket so a 22cm braided strap is a nice fit. Always use braided for engine/gearbox earth straps for their flexibility with engine/gearbox movement, insulated stranded cables are intended for fixed items like batteries (having said that the 12v cable to the starter is insulated and stranded but it's free length is much longer which gives it more flex without strands fracturing). Comparing sources as I do, Halfords just down the road have one at £2.59 whereas the cheapest eBay is over £5. The hole in the chassis rail bracket is pretty big at 15mm so I'll need an M12 x 20.5mm shakeproof washer (outside serrations) to sit between that and the earth strap lug to ensure a good connection and two largish flat washers to clamp it all together. All a bit of a fiddle as well as grovelling underneath. A strap with 10mm terminations would have been preferable for that location.

But having just discovered that late 1980 4-cylinder models gained a more accessible engine earth strap from a gearbox bolt to the gauge hose connector mounting point on the heater shelf I wondered if that was a possibility on the V8. It could be but the gearbox bolts are recessed into the tunnel on the V8 more than the 4-cylinder and would probably need the air-box to be removed if not the carbs complete, and the V8 does not have the oil gauge connector or its mounting bolt. An alternative high position from an alternator bolt to an oil filter housing bolt was a possibility but I didn't want it to interfere with changing the filter - that's a bit of a fiddle anyway having to slacken the three housing bolts to get my chain wrench round the filter, and detach the outlet hose from the housing to make enough space to get the filter out and back in.

Another possibility is between alternator and radiator mounting bolts running past the other side of the oil filter, or the other side of the engine from the lifting bracket bolt, but I'm wondering if the relatively flimsy panel spot-welded to the inner wing is less than ideal as an earthing point. From a lifting bracket bolt to an expansion tank mounting bolt was briefly considered but the tank would no longer lie flat against that inner wing. From a lifting bracket bolt to a near-side wing mounting bolt, under the flange, is yet another, with a longer bolt and second nut (like the support bracket for the bonnet release cable) as the existing nuts are welded. Very little engine movement here as it would be right beside the steady bar, but the bolts are nicely painted and a new one would need painting to match. Which leaves underneath.

In the end, given that the diaphragm panel has got to be more robust that the clutch hose bracket, and it's much easier to get at, I opt for plan C i.e. between alternator and radiator mounting bolts which is by the oil filter but not in the way of its removal. In less than an hour it's on and there is now only 0.1v difference between engine and body so well worth it. A bit of a mystery as to why - when they recommend one for DIY installation of the gearbox - Vitesse don't fit one as part of the installation you are paying them for when they have a 2-post lift, but there we are.