Nigel Clark

Check the old gudgeon pins visually for wear marks and if they all appear clean and unmarked, I would reuse them. You could also measure their diameters at different points using a micrometer as an additional check, though probably unnecessary if they are free from visual signs of wear. Nigel

I would echo Clive's advice regarding uprating the Spit 1500 engine. Don't forget the brakes if the car is going to be driven hard. The standard system is good if well maintained but needs decent pads for the front discs. Ideally, fit Mintex 1144 pads in place of standard, overhaul the brake system and fill with fresh fluid. Nigel

That happened on my GT6 and I had to weld up the hole and re-drill. The oval hole resulted in a bit of lost movement and a rattle on rough roads that took ages to diagnose. Nigel

I've only ever seen vacuum take offs for carb balancing downstream of the throttle butterflies on multi-cylinder bikes, where each inlet tract is separate and not connected to the others while testing. I've tuned three and four cylinder bike engines this way with a bank of vacuum gauges but never a twin carb car engine. With a Triumph four or six cylinder set up, there is a large balancing pipe on the manifold which will tend to equalise vacuum downstream of each butterfly. For balancing these carbs, I believe it's the airflow through each carb is what needs to be matched or balanced. And the airflow is detected either by listening to the hiss with a tube in the mouth of the carb, or with an airflow meter. I'm happy to be corrected if wrong. Nigel

Like Pete, I've always balanced twin SU or Stromberg carbs by listening to the hiss with a tube held in the inlet, or by holding an airflow meter in the inlet. This type of meter is widely available and works well enough: https://www.ebay.co.uk/itm/STE-Carburettor-Synchrometer-Air-Flow-Meter-SK-40-42-45-48-SU-Weber-Dellorto-ADV-/352992790086?mkcid=16&mkevt=1&_trksid=p2349624.m46890.l49286&mkrid=710-127635-2958-0 Nigel

Chris Witor's site has excellent technical info, though I believe his cylinder head data only covers later 2 litre and 2.5 litre types. Nigel

Nice looking car, the Revolution wheels suit it perfectly. And there definitely is space for a centre silencer between the chassis rails on all GT6s, it's tight but it does fit. Nigel

When I acquired my GT6 about 20 years ago it didn't have a centre box but that didn't make it correct (I've since fitted a centre box). Rimmer Bros website shows centre silencers on Mk1 and Mk3 GT6 but not Mk2. Nigel

Exactly what I have found re the centre silencer. I believe Mk2s had the centre silencer originally and Triumph deleted it for the Mk3, probably cost saving. But the centre silencer does fit on the Mk3. Nigel

Yep, code 72 Pimento. Nigel

One further point to consider is whether to fit a centre silencer. Some GT6s had a small silencer between the manifold and the main silencer at the back, in between the chassis rails, and some didn't. Pro's and cons of the centre silencer as follows - Without the centre silencer the exhaust note can have a bit of a rasp, it's not quite so well muted with only the back silencer - With the centre silencer the exhaust note is less intrusive but it's a tight fit between the chassis rails and can rattle. Normally if the exhaust is fitted carefully with all the correct mountings, it doesn't rattle. I have both silencers on my GT6. Nigel

The Bells semi sports system from the Club Shop fits your description and is guaranteed for as long as you own the car. It's single pipe from manifold to silencer. The silencer hangs in the same position under the boot floor and exits via twin pipes under the bumper, as original. The only only difference is the tail pipes are larger diameter polished stainless. I would describe the sound as purposeful rather than loud. Here's a pic of this system on my Mk3. Nigel

That could be something for the Club Shop to organise. Nigel

Tracy Tools may be able to help with the reamer: https://www.tracytools.com/ Burlen Fuel Systems have a comprehensive list of spares for Stromberg (and SU) carbs so may be worth trying for the bushes: http://burlen.co.uk/ I've used Burlen several times for Stromberg and SU parts. I never dealt with Tracy Tools but see them advertising in classic bike mags. Nigel

NOS can be good but with a wiring loom, I would be a little concerned that the vinyl insulation may have lost plasticiser and become hard and brittle over nearly 50 years in storage. Not as bad as when exposed to high temperatures under the bonnet perhaps, but personally, if I was rewiring a car, I would play safe and buy a brand new loom from the Club Shop, Autosparks etc, avoiding the risk of old insulation failing. Nigel

Good advice above, it may simply be a cheap fix with new thrust washers. I can also vouch for Ivor Searle, having shot a feature on machining a Spitfire engine for Practical Classics in their factory. I also had them refurb my Scimitar's cylinder heads and convert for unleaded. Top quality work at fair prices. Nigel

Do you mean none of the instrument lights are working, or none of the instruments give any reading? Assuming it's the lighting, the problem is likely be an accidentally disconnected live feed to the instrument lights (white/red wires), or earth (black wires). Nigel

The advice above is spot on. One other little tip... Don't wait for the new gasket to arrive, start squirting the manifold/downpipe nuts and studs with penetrating oil now, and repeat every few hours to give yourself the best chance of removing the nuts without snapping the studs. Use a proper penetrating oil like Plus Gas or the there's a 3 in 1 version that works well. Don't use WD40, although it's great as a water dispersant, it was never meant to be a penetrant. One other tip if the nuts are stubborn is to heat them with a blow lamp but be very careful of the carbs and petrol nearby. Nigel

The Blackline limited slip diff in my GT6 is an aftermarket product, working on the principle of rising helical gears. Nigel

As you already have the Blackline differential, which Paul would normally supply, I think you need to call him for a price. Nigel

+1 for Pete's advice on the seal. Once you're certain you have the correct seal thickness, there is some adjustment in the latch mounting screws and if one corner still sits proud, you can try shimming the hinge mounts with gasket paper or washers. It's also possible that the hatch frame is slightly twisted if it's up on one corner. Nigel

My 1970 CP series TR6 has an A type overdrive, which has worked fine during about 15 years ownership. I can't comment on differences in numbers of springs, hadn't heard that before. Something to watch out for is the gearbox/overdrive breather. Some applications have a breather hole at the front of the gearbox top cover, others have a brass breather fitting on the overdrive casing. When mixing and matching gearboxes and overdrive, it's possible to end up with no breather, inevitably resulting in oil leakage. Nigel

That's the solution I've used for mg GT6 2.5 litre. The 3.27:1 ratio is ideal for the torquey 2.5 litre engine. The weakness of the original Triumph diff has been mentioned in previous posts. Paul Hughes at 2Spec built me a 3.27 diff using a Blackline limited slip diff, which should overcome the weakness of the original. Nigel

I've used Bosch WR78 and NGK BUR6ET multi-electrode plugs successfully in Triumph four and six pot engines for about 15 years. Sorry to contradict, but my experience is that I've had absolutely no problems with these resistive plugs, indeed they've given easier starting, smoother idling and crisper acceleration than the standard non-resistive single electrode plugs. all a little subjective, and merely my experience. If the ignition system is in good condition, I would say resistive plugs are perfectly suitable for our cars. Nigel

I fitted a tubular manifold to my GT6 20 years ago. Never had a problem with it. Don't know if it makes any more power though! Nigel