Jonathan Kay

There's a trick with a magnet for locating hidden tubes*. Jonathan * Cue pun about coming over here and finding our poles...

I've just had second thoughts... but the principle stands. ;-) Jonathan

AMENDED Do you want a manual override? Expert advice, please: is it better practice to use a relay to use that switched earth to switch the feed or to make the feed permanent and switch the fan earth? (I can work out the wriing either way.) And if the latter should you add a relay? Jonathan

Second reminder for S7_248. Jonathan

It's quite a long and winding road through the multiple threads, but it looks as if it's the same as on the Vauxhall engined 7s: Thermostatic fan switch for rad; VW part VW823959481F There's also a suggestion of: Commercial Ignition (quniton hazell) XESF29 available as an alternative to the 'proper' vw one. motor factors and halfrauds for circa £6 Jonathan

There's a VW equivalent. I'll try and fix the link. Jonathan

Did you ever sort this out? Some interesting data on Duratec cooling has just appeared in this thread. Jonathan

Thanks for the update: very useful data. Isn't there an unresolved discussion somewhere about cooling a Duratec in the USA? Jonathan

I don't think it's in the Guide. Myles has "13mm bolt" which I think means 13mm head so probably M8. Are yours standard, and how old? But what options do you have... ? (And why are you changing them?) Jonathan

I used a Firwood floor paint on top of their sealer. It hasn't lifted but it can't take the pressure of the Vespa stand. I'd use a two-pack epoxy if I were doing it again. Jonathan PS: Are you doing the bottom of the walls? It adds quite a lot of light under the car.

2mph error is pretty good. But needle on dial speedometers are a very poor design for display. As it happens there's a fix that improves both the accuracy and the speed and ease of reading. Find the correct dial position for the speeds of interest, eg 30 mph, 50 mph, 70 mph using a GPS. Then mark the dial with a radius line using Letraset or similar. It's much easier to spot the needle in relation to a line like that than to a tag mark and number on the outside. This can also help when a small steering wheel hides some of the dial. Jonathan

... it may be a brilliant product but why is it not a OEM fitment if it's so much more performant ? a manufactor would be able to use smaller waterways in the engine and smaller radiator = less cost and a lighter car That comment about early 911s was harking back to Setright's wonderful observation that all car engines are air-cooled but some interpose another fluid. And I still haven't found the original since our discussion of VW Transporters. Is it possible to design much better cooling systems? In the last throes of very high performance piston engines for aircraft we saw evaporative cooling, 100% ethylene glycol and thrust generation from the waste heat. (All of those were studied in the development of the Spitfire and Merlin and are therefore very well documented.) In highly specialised cars there's a load of cold water without a radiator in drag racing, and the use of pure water in some racing cars. I think the latter is to get the greatest thermal capacity in a setting where freezing isn't a risk because you're prepared to drain frequently. Has anyone used waste heat from the cooling system to blow aerodynamic surfaces (as with F1 exhausts) or to generate thrust? But the most widely used technique is to use both oil and water as intermediate fluids. The 911 engines were the best and most persistent attempt to only use oil in a road car. This discussion prompted me to have a look at how they worked. They all had something like a radiator although the early ones hid it away. The exposed piping was responsible for quite a lot of the loss. But as the power went up they moved to bigger "external" radiators. And eventually they had to add the second fluid. Are there any estimates on how much heat goes which way in high-powered 7s with oil coolers? I don't think you could produce a radical design with big gains around waterways and radiator size based on propylene glycol: the thermal capacity is too low. But are there any other exotic fluids that would make it possible? Perhaps using a phase change? Or any good recent articles on heat management in F1 engines? In the days when I was interested there was an interview with someone who was designing a new F1 engine from scratch for a new formula, and his view was that heat management was the first thing to be considered. It might have been Duckworth and was certainly after the DFV era. Jonathan

Thanks: agreed. But is that the stuff widely sold for domestic use? Jonathan

Brake cleaner is prettty aggressive, and there's a big range of different constituents in different products. In general I'd keep it away from rubber and plastics. It's unlikely to leave a residue. What is the gasket made of? Could you post a photo of the affected area of the gasket? "Silicone remover/ cleaner" is available but I've never understood what it is. I wonder if petrol and a very gentle scrape might be the best method. Jonathan PS: Did you decide to sort this out yourself after the garage's effort?

The voltage figures don't suggest failure. I'd disconnect the panels, put a known load on it (with an ammeter if possible) for a long time and measure the capacity. Jonathan

Those voltages are a bit high: what sort of meter? Is it the sort that needs topping up? Jonathan

Is it a 12 V system? Why do you think there might be a problem? Jonathan

There's quite a lot in the archives on what's needed and the problems in practice, and some experiences with individual models: try this search. I'd be interested in what you choose, and how many might be interested in another Bulk Buy? Jonathan

How about the hole in the tunnel? (I'm happy with the approach from below, have sawn off some hex section, and won't be repeating the ratchet spanner fiasco now that I understand the subtle difference between the two types. And mine doesn't lose any oil.) Jonathan

... and can see the reasoning from all points of view. http://www.mirrorsforsevens.com/images/index_picture1.jpg :-) Jonathan

Discussed here, with Mankee's photo: (If that image doesn't appear inline, try here.) Jonathan

... what is the difference between wide track and narrow track suspension? You can buy bits from Caterham that hold your front wheels further part, eg: http://caterhamparts.co.uk/img/p/4089-4095-home.jpg#sthash.hV7wA8D0.dpuf Discussed here. Jonathan PS: Isn't there a problem with quantum suspension: if you position the car exactly how can you be certain how fast you're going?

Quaife make a top cover with an access hole: http://cfront.burtonpower.com/media/catalog/product/cache/1/image/285x/dbee39002c3ed3c5438224ee0989910f/G/B/GBT9101_Top_Cover_4.jpg Which way do you get to yours: up from below or through a hole in the tunnel? Jonathan

Do you want to upload photos from your computer directly or to use a hosting service? Ian B's incredibly helpful Guide, which describes both. Jonathan

Does the Club have a theme tune? ...Jonathan