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I have used the std mk1 2000 stuff, spring, damper, needle etc. I am picking up the 1360 carbs tomorrow on semi-permanent loan, so can try those piston weights. See what effect it has. I will also dig out another wideband setup, possibly from the spitfire (though I need that this weekend for a trip, Gill is jumping out of a perfectly good aeroplane. Utter madness) As before, there is no clear progression with these carbs. Heaviy piston-light spring-heavier spring goes alongside progressively weaker needles, but as said the 6J 2000 mk1 needle is not too diffrenet to the 7J 1600 one. Anyway, I am on slightly restricted duties today and tomorrow as I have just had a steroid injection in my rather arthritic toe. Beginning to get painfully throbby now the local anaesthetic has worn off. Gill has read the "instructions" so no faffing around under cars etc.

Pity Alan OTU is no longer with us as he was good at this game….. I do agree with Colin’s suggestion - got to be worth a try as it wouldn’t take long. ISTR that there is/was a fella (Pete?) on the TSSC forum who’d done a fair bit with 1600 Vitesse fettling…..

Tuning Stromberg carbs. You must relish a challenge! Just a thought here but if you are running the Mk2 cam with a much higher than standard (for 1600) CR then the basic 1600 carb tune is going to be way off in pretty much every respect. With those mods I am guessing that you will be getting something like Mk1 2000 performance, or maybe a little more, from the 1600. Given that Triumph went for springs rather than just piston weight for the higher engine powers it is likely that there was a reason for this. On that basis I would have thought that rather than trying to adjust piston weights to try and match the piston lift to air demand (something of a rat hole I would aver) you would be better of with fitting a spring. And the 'light' spring from the Mk1 2000 would seem to be a reasonable starting point given the likely engine performance. You could also start with the Mk1 needles too. And by remarkable good fortune it would seem that you probably have a good stock of those.😁 Just a thought... I am with Nick on the AFR values you seem to be getting though.

I do like the XJC and very nicely proportioned car. Nice wheels those. And rmoving the vinyl from the roof is a major upgrade in my opinion. Although a non-trivial undertaking I would imagine. Definitely would benefit from being lowered a couple of inches in my opinion too.

My thoughts exactly, I had fuel pooling in the carbs and dry plugs. But perfect compression. Somthing didn't add up I'll seal it up priperly if I get time tonight and start again from there i guess! I remember a similar situation on my mini once, in traffic, the breather from the block to the carb decided to come off, i had to rev the tits off it to keep it going and not conk out

Thank you, yes it's definitely the culprit, I tightened the manifold bolts and carbs whilst trying yesterday. When I had the engine running, I was spraying easy start and wd40 around the manifold gasket and carb gaskets listening for change in tone, but nothing so they must be all good. Didn't think of that bolt! Yes, fibre washer either. This explains so much

I have uploaded this video link to save file space above https://youtu.be/Vet3iuNH69g?si=MAG6pthsoAYnYEd_

I recon that's a good candidate for the frustrations. An air leak of that size could make it run exceptionally lean at idle. It not only provides more air, but reduces the vacuum the carbs see so they won't draw so much fuel. Fingers crossed here that this is the source of the issue.

That would explain the dry plugs and consequent failure to proceed. Air leaks are very much a major issue with carburetted engines! I take it you have a copper washer on both sides of that aloy plate holding the return springs. With that lot found tomorrow should see a mjor improvement. Good luck

By chance, I think i found somthing whilst packing up. Now I can't confirm whether or not it was like this before I tried to run it, it's possible, or if it's worked its way loose. the larger blanking bolt on the top of the manifold was loose. And the little one to the side where someone had a servo previous doesn't seem like it's selling well and the threads appear stripped. its not clear but there does look like there's some fuel in that breather channel. That could explain a lot? The smaller hole i need to tap it to a larger size, I've removed the larger bolt so whilst tapping I can get the hoover over it to suck any shavings that might go into the passage. Anyway, if it was loose before it would explain the bad starting, do air leaks honestly cause this much drama? I'll still go through and check everything else again and hope for an improvement.

I'll check again for leaks. Yes powerspark Nick, same a accu spark more or less. I'll check the gap, the dizzy does have quit a bit of play up and down on the shaft. I managed to get it timed to about 13 btdc and able to start it again. But it's very lumpy and very hard to get started even on a powerlite starter. Got to mash the hell out of the throttle to get it going. I managed to get it to a point where I felt comfortable to drive it a few hundred metres. And horrible scraping noise coming from somewhere. It only does it when the drive train engages, won't do it whilst stationary with the engine running nor jacked up and wheels rotating etc. Sounds like metal on metal. I thought it might be the exhaust scraping on the drive shaft but no visible wear on the paint. At the moment the engine is the priority to get that to a decent point. This is another headache. God I hope it's nothing clutch or box related. Am I right in saying the timing with the strobe will always be what the manual states(13°) irrespective of what cam is in it? I want to check valve clearances again and float level to rule them out complelty. The car ran beautifully before, chuck all that time and money at it and it's somehow worse.

Woohhh hoooohh

Yes, I think you are right. Possibly you can experiment with other weighting methods for trial purposes? Definitely be wary of the wideband readings you are seeing. Seem very extreme to me and incompatible with running “ok”. Odd though, if the display and controller are matched items there shouldn’t be any range/span issues!

Assuming you have an Accuspark or Powerspark EI, how big a gap do you have between the unit and magnet ring? Might want closing up a bit?

Check for air leaks again.

Reasonably, sounded perfect, now hesitation etc. I did just get it going again, I got my sister to help whilst I twisted the dizzy and got it to go. Plugged the vacuum and strobed it and the pointer is prohably about 50 degrees or so btdc! I can strobe it and whilst adjusting the idle screws to about 13 degrees btdc. As soon as I switch off, it will not restart again, unless I move the dizzy back to where it was before the strobe. I'm stumped

Would need to be a BIG air leak…. How ?well was it running when it was?

Well some good news, the water leak fix worked. Had it running but had to switch it off as all the coolant that spilt was making a very unpleasant steam room. I now however cannot get the thing to go at all. I've checked static timing again with the bulb between coil- and ground until it goes off. Just won't kick at all. Fuel is puddling out the carbs and the plugs are dry. No fuel to cylinders? Makes sense. Am I right in saying there must be an air leak? Driving me up the wall.

Indeed, they are Series 3 Kent alloys. The intrepid owner has also fitted the 'challenging' Series 1 wing mirrors and, as an act of selfless bravery, removed the vinyl roof covering. Lovely as it is, it does look as if it's riding high, though.

There's a youtube series of a chap who recently rebuilt a mk3 engine which is well worth a watch as a guide/refresher on what to do. Red fox classics I think it is.

I picked up an unknown Spitfire Mk. 3 engine in the winter, I haven't really looked into its condition yet other than seeing the plugs were oil fouled (evenly, at least), but the crank end float feels okay so hoping its rebuildable. It also came with a Spitfire Mk. 4 3-rail gearbox, which I think I can make work... There are a few caveats, but I have worked most of it out in my head already. No doubt I'll be asking lots of questions to confirm my ideas are sound as a lot of it is unfamiliar territory for me. Thanks for the offer of engines, will keep you in mind if what I've bought ends up being bad.

LD performance with a genuine bosch 4.9 I wish it was a "dial" gauge, but instead has big red led numbers that change rather fast.... I do have 2xcolortunes somewhere, I will dig them out. I have also discovered there are several different piston weights. At least it seems to be the diaphragm clamp ring that varies. I might play with adding weight, but I will see what happens with the 1360 bits.

What engine are you wanting to end up with? We have a small crank Spit 1300 that runs well apart from needing exhaust valve seats. Also a 1360 block, crank, head etc needing rebuild but still on original sizes. The latter is free to a good home!

Interesting, though I’m a bit wary of your wideband. 9 at idle should be black smoking, mid-firing, hunting and surging rich. Likewise, it should be hitching and hesitating, even falling on its face well before 20! Which wideband is it and what are you using to read it with? At idle, you could use a colour tune plug as a sanity check. Change from orange to blue occurs mid 14s

Didn't realise your in Wick, spent a lot of my childhood in Melvich, such a stunning part of Scotland. We head up quite often to the NC500, the weather has brought out a lot more unusual cars ( Porsche club seem to be up every weekend ). My favourite so far was an old boy towing his mint Morgan behind an equality trick Defender, apparently the wife only enjoyed short journeys in the Morgan