Nigel Clark

I would expect the male connectors on the stabiliser are for the 12V supply, and the female terminals are for the instruments. It's a matter of safety, the wiring loom terminals are less likely to short out if female terminal on the loom connects to male terminal on the voltage stabiliser. However, can't guarantee this, so look for engravings on the back as Pete says. Nigel

Practical Classics magazine publish a classic car price guide, regularly updated by their market guru Russ Smith. You can download it here: https://static1.squarespace.com/static/5d31c18a98e9ae0001ecd934/t/5e271cbe9e40e20770b6e954/1579621578638/IPAD+Price+Guide+March+2020.pdf The TSSC insurance value of an A1+ Spit 1500 is £9,000, so using Clive's factor of 2/3 (which I agree is a good rule of thumb) that's £6,000. Practical Classics value a Condition 1 car at £5,250. It always helps to have multiple sources of information when trying to estimate the value of anything! Nigel

Rough 4 or 5 cylinder start up isn't unusual for Lucas PI TR6s. The two most likely causes are: - Faulty injectors that dribble and don't hold line pressure when the engine isn't running. Sometimes a good blow through with compressed air will clear traces of dirt and cure the problem, sometimes a refurbished injector is needed. - Non-return valves on the metering unit outputs to the injector lines failing and allowing pressure drop. This most often happens on cylinders 2 or 5, where the lines are connected by banjo bolts rather than straight unions. Slivers of rubber seal or dirt in the fuel are the most common culprits. When replacing any rubber seals on the injection system, only purchase from a recognised Lucas PI specialist. Some of the others may be the wrong type of rubber, or a metric 'close equivalent' to the original imperial size. Nigel

The J type from an 1850 Dolomite should be 25%. Nigel

Nice ratio, not easy to fit, but I imagine it would be bomb proof. Nigel

I'm still a bit torn... I really like the idea of relaxed cruising with the 3.27 final drive and reckon that the 2.5 litre engine with its long stroke and ample torque will pull the high 1st gear. Then again, as my thought process goes, 3.63 diffs are more widely available. And this ratio would give better acceleration through intermediate gears, with reasonable cruising in overdrive. The only certainty is that a 3.89 final drive in a GT6 with a bigger engine is too low. Decisions, decisions! Nigel

The Dolomite 1850 has identical ratios to the GT6/Vitesse 2 litre box. Nigel

At the moment, I'm running completely standard transmission, including the original gearbox and D type overdrive. Inevitably, this won't last long with the torque from the bigger engine. As well as the switch to 3.27 final drive with the LSD, Paul at 2Spec will build me a hybrid gearbox, with Dolomite 1850 internals in the original gearbox casing with J type overdrive. Nigel

Hi Peter, The 3.27 crown wheel and pinion do require some machining inside the casing to fit, if using the casing from any other ratio diff. I believe the pinion bearings are different too. My plan is to have Paul Hughes at 2Spec Transmissions build it up for me with one of his limited slip diffs: http://www.2specgroup.co.uk/transmissions/triumph/ This is for my 2.5 litre GT6, which I feel will easily pull a much higher ratio. The 3.27 diff is said to be the weakest of the small chassis ratios, but my understanding is that it's the differential rather than the crown wheel and pinion that are the Achilles heel. The 2Spec LSD should get over the weakness of the original differential. I'm not in a rush, so I'm going to keep looking, hoping a 3.27 diff will turn up. In the meantime, 2.5 litres plus a 3.89 final drive does make for amazing acceleration! Nigel

Thank you chaps. Ideally, I want to be able to drop the 3.89 from my GT6 and bolt in a reconditioned 3.27 as a direct swap. I'm trying to avoid cannibalizing my present diff to build the new one. Life always seems more complicated than it should be, especially when modifying a Triumph! Nigel

Hi Dave, Thank you for the heads up, don't know how I missed that one! It's got a broken crown wheel and pinion and it's a 4 stud spring mounting (unusual for a 3.27 diff), whereas I need 6 studs for my Rotflex GT6. I'm going to hang on and hope for a better starting point from which to build a new diff. Nigel

The short answer is NO. If the oil pressure is low, it's because the oil pump and/or bearings are worn. The pressure relief valve is a spring loaded valve. As engine revs rise, the oil pump is running faster and trying to deliver more oil, potentially causing excessive pressure and leaks. The spring on the pressure relief valve allows its piston to rise, so some of the oil delivered from the fast-spinning pump is diverted back to the sump, instead of following the usual path via the oil galleries to the crankshaft and cam bearings. This controlled return of excess oil to the sump prevents the pressure rising too high. Packing the pressure relief valve spring with washers will delay the point at which excess oil pressure is vented back to the sump, so at high rpm the oil pressure may be too high. This becomes more of a problem when the engine is cold and the oil is thick. The Triumph engineers did a good job when they designed our engines' lubrication system. My advice is don't try to adjust the relief valve and don't add one of those external rocker oil feed pipes either. The only modifications worth fitting on the lubrication system are a spin off filter conversion for six cylinder engines, and possibly an oil cooler with thermostat for highly tuned engines that are regularly driven hard. Other than that, keeping the lubrication system standard is best, with regular oil and filter changes. Nigel

GKN uprated universal joints, as sold by the Club Shop are worth the extra in my opinion. At £15 each (members' price), they're not expensive compared to the aggro of fitting and then soon having to replace a cheap UJ. Nigel

Best chrome plating, the firm I've used, is west Midlands, ACF Howell in Walsall. Derby Plating are also highly rated by some on the TR Register forum, though personally I've no experience of their work. You can use Google to find either. Nigel

Thank you gentlemen, I will follow up. Nigel

How did that needle get broken... Could it have caused damage to the cup that the needle was sitting in? Before simply adding another roller, I would want to check that the cup is okay. Nigel

Hi Julian, Well done in getting another round tail Spit back in the road! The H gate on a 3 rod Triumph box, as fitted to Spitfire Mk3s, is wider than some cars from the same era. For example, the MGB has a much narrower gate. Does the gear lever waggle from side to side much when a gear is selected? If so, there could still be some play in the remote selector linkage. This may be cured by carefully tightening the bolt on the fork at the bottom of the gear lever, and also the bolt in the fork half way along the remote linkage. Take care, as over tightening these bolts will make the linkage too stiff. Nigel

As above, does anyone have 3.27:1 ratio diff, as fitted to non-overdrive GT6s? Condition is unimportant as long as it is suitable for rebuilding. Please PM me if you have a 3.27 diff you would be willing to sell, or if you know someone who does. Thank you, Nigel

Yep, duck for cover! A good GT6 is reliable, well at least as reliable as a Herald. And as classic cars both will allow you to arrive in style at your chosen destination. But if your chosen destination is more than 10 miles away, there's only one choice! It comes with a 2 litre engine, 6 cylinders and overdrive. Time for my tin hat. Nigel

Looking forward very much to meeting again soon, and comparing notes on our GT6s. Sorry to say, the GT6 cooling system is marginal for hot weather. There are various threads on this forum with ideas and differing views on how to improve cooling capacity. My research and experimentation on this subject suggest the with the cooling system in good condition, airflow through the core of the (marginally sized) radiator is the most critical factor. Nigel

Richard, I'm glad to find you've retained your scientific curiosity and rigorous approach to research since we worked together more than four decades ago. However, during those decades health and safety have assumed far greater priority. We should certainly not be inhaling petrol these days, it's far more harmful now than in the seventies when it contained lead! Nigel

Dave, Good to see Finn enjoying life with a Triumph, he's a big chap. Jasper (my spaniel) is a working cocker that doesn't work. He's a rescue that's been absolutely devoted to me since we gave him a home just over 6 years ago. He's supposed to be 11-12 years old but recently has suddenly seemed a lot older and has developed a debilitating balance problem. The vet says it may clear up temporarily but there will be recurrences. Here he is, enjoying the TR6 a few years ago. Apologies for the thread drift! Nigel

By the way, the hoses in that photo are Club Shop silicone, over 10 years old and still in fine condition. Pete, I hope to get to Duxford but my elderly spaniel is a bit poorly and always very anxious when I'm not around. At this stage of his life, his needs may have to take priority. The things we do for our animals! Nigel

Here's how the GT6 Mk3 thermostat housing and top hoses should look. Nigel

The convoluted top hose is correct for a GT6. With a genuine GT6 thermostat housing, the top hose run is short and straight. The convolution is necessary to absorb engine vibration, not as a bodge to get around a curve. Nigel