Roger K

Great stuff! Just to say on the exhaust, you can weld a stainless exhaust with a Mig, using ordinary mild steel wire. It works just as well, you just get the welds going rusty before the exhaust does. Or you can just buy a small role of stainless wire and use that on the Mig, same gas. I do it all the time, no problems. I do Tig as well, but for exhaust repairs it's just easier to use the Mig which is much more user-friendly for an exhaust that's still on the car!

2BA is easy enough to find. Namrick stock them, amongst others. Slotted head, usually - round or countersunk.

Yes, it all looks good. I’ll just add the O/D in and see how I go! Thanks all. What a helpful forum!

Just checked the speedo, and the tpm is 980. I know for sure that this speedo was in the car in 1976 so it is almost certainly the original, so the diff should be a 3.27. Car was first reg in late ‘73. The number stamped on the underside of the diff is KC81416, last digit might be a 5. Any help identifying it?

Yes, my XK140 is like that. I'll be fitting an unleaded head when I do the job as well, so while the head's off I'll stick a dial gauge on no.1 and check TDC against the pointer.

Did the GT6 ever have that? Don't remember ever seeing one.

I need to look at the numbers on the casing. As Rob suggests above, I have a vague recollection that only the overdrive ratio (3.89) was fitted to the very late cars. That said, it's not going anywhere with the rear spring out whilst I get around to fitting the correct GT6 one that arrived yesterday. It'll be nice to get rid of the positive camber, courtesy of the Spitfire swing spring...

Car is a late (post KE2000) non-roto GT6 MkIII. The lump of sound deadener on the front of my timing chain cover has been damaged for ages, trapping water behind it which has finally produced a leak in the timing cover. According to my original BL parts book, this is part no. 207492, but according to Rimmers this is the correct number for the Vitesse 1600 cover, which is NLA. Rimmers show the GT6 part as 217069 - is this correct, and will it fit a late GT6 OK? Thanks, Roger

Thanks for the advice. The car's not running at the moment so I can't comment on the revs, but your comments on the single diff for later cars rings a dim, distant bell with me from the eighties when I had six very late GT6s (yes, all at once - don't ask). I'll fit the gearbox and see how it goes. Roger

I have bought an overdrive gearbox to fit to my non-o/d late GT6 Mk3. I’m wondering whether to leave the non-o/d rear axle ratio in, to give better motorway cruising for the modern world - any thoughts?

My 'new' GT6 has sealed beam headlamps still, which I think I'd like to change for halogens. I'm wondering what the perceived wisdom is on wiring - does the stock MkIII rocker switch handle the increased current OK, or would you recommend sticking some relays in there? I'm assuming the current is increased... Thanks Roger

Depends what cars you are working on - my AC and Jaguar are both predominantly BSF and BSW, with all small fasteners on both cars being BA. Engine parts tend to be a mix of UNF and UNC (unified fine and coarse). The AC has an American engine, so I'd expect UNC threads on that, but I was a bit surprised they were so prevalent on the XK engine. Cars from the fifties and earlier used BA liberally for small mechanical items, body fittings, everything on the dash etc. My Series 2A Landie is also almost exclusively Whitworth and BA. As a result I have several sets of taps and dies, mostly from http://www.tapdie.com/ . Their range is huge and quality very good - as usual with tools, you get what you pay for. I only use split dies, so if I'm cleaning up a thread I can screw the spreader screw in and the die takes a light cut only. If cutting a new thread I usually do it in two or three passes until the thread fit is snug and not loose.

I too have a Lincoln Viking 3550, and very nice indeed it is too. I've had a few auto helmets and you definitely get what you pay for. They can be had for under £200 and at that price they are a bargain. I have the optical screen as well, as once past 60 the quality of your welds becomes inextricably linked to your ability to see what you're doing. I use mine with my trusty Portamig and a R-Tech AC/DC tig, works great. I've been using it for a good few hours a day over lockdown doing the bodyshell on the XK140DHC, which is now just about ready for paint. Roger

Thanks - and yes, I've discovered the last bit!

Could someone tell me if the clip-on seam cover under the rear quarter, below the side sections of the rear bumper, on a late MkIII GT6 should be black (like the very visible ones on the top of the rear wing), or body colour? Thanks, Roger

Just to follow up on this - I made up a pair out of mild steel bar, which has done the trick. Solid as a rock and I haven’t had to use nuts on the inside of the mountings. Thanks all!

Thanks Ben, but those are 5.5s and it's 5s I need. I don't think the offset of the 5.5s will work with non-roto driveshafts.

Good man - fingers crossed!

Thanks for the advice Peter - I really want to keep this GT6 looking as standard as possible, so will probably end up keeping the 4.5s. It’s not had a single mod since it was built, not even an unleaded head. I have a set of 5.5 reverse rims but they are a problem with the non-roto long drive shafts, and look a bit too much for my taste, so I need to find some 5” rims. I’m happy to pay top dollar!

Thanks Mark, but still looking, folks....

Hi Mark, pm sent. Thanks, Roger

If you have a head gasket fail it's always a good idea to check the block deck and head face for flat with a good quality straight edge and feeler gauges. Sometimes head gaskets fail for a reason!

As it says really - I'm looking for a set of 5J x 13 steel wheels as fitted to Spitfire 1500. I have a set of 5.5 x 13 (Formula Ford) wheels I would happily exchange if required. Please send a pm if you can help. Thanks, Roger

I'm planning a full rear end rebuild so once I get the driveshafts dismantled I'll be able to measure accurately. I've bought a spring from Rimmers - it has a different part number from the Spitfire 1500 spring and is listed as only fitting GT6 Mk3 non-rotoflex, so hopefully it'll be right. Its number is 159654 whilst the Spitfire IV and 1500 is 159650, which is what my car has currently fitted. I'm used to settling leafsprings. One of my cars has a front one and a back one, so double trouble! As the GT6 spring settles, would that result in more negative camber? I'd presume at rest the spring would sit with a downward curve at the ends, meaning that settling would produce more positive camber.

The late '73 non-roto GT6 I have just bought is suffering with rather odd positive camber on the rear wheels. I have checked back through the invoices that came with the car, and it turns out a few years ago the car was fitted with a new transverse leafspring, the part number of which ties in with a late non-roto Spitfire. This is a different number to that for the GT6, so I have ordered the correct part. However I'm confused, because the car has positive rear camber. I would expect the GT6 to be heavier than a Spitfire, and therefore to use a stiffer spring. Surely with the weaker Spitfire spring it should have negative rear camber? Thoughts welcomed. I'm wondering if the drivshafts are the correct length (although there's no record of them having been changed). Could someone tell me the correct length of a late non-roto GT6 driveshaft, please? Thanks, Roger