johny

If theres no pinking then theres no need to use an octane booster either as an additive or a higher RON fuel in any of our cars. Remember the power available in the fuel isnt changed by its octane level.....

We're going round in circles here: 'unless you want to maintain standard timing and the engine pinks excessively (see test above) in which case you could use an octane booster which might as well include a lead substitute'.....

Brian I really recommend going through the complete sequence of engine adjustments rather than just stabs in the dark. If you do that you then know 100% that those things are right and if theres still problems it narrows down the search and can save a lot of time......

Cant find much info on Dynolite as to exactly what the lead substitute is (not supposed to mix different types) but have noticed that the product with octane booster works out rather more expensive than I thought as its 250ml for only 40L of fuel (25p a litre!). The Millers and Castrol equivalents at around 20 quid to treat 500L are much more economical....

Thats not a bad price although Dynolite wasnt one of the VSR additives approved by FBHVC (however apparently all the various companies invited for testing had to pay for it themselves so some judged it to be uneconomical and declined.....)

yes I think you have to match the petrol octane to the engine compression or even the other way round if, as in some countries, the necessary octane additives arent available. Of course if you have got a higher octane petrol you can run more compression and so make more horses even though the energy content is pretty much the same whatever its octane.....

I imagine if you take the octane too high you might actually be making the mixture more difficult to ignite or certainly changing its combustion characteristics....

If you carry out the test as described you will end up with the correct octane to run your engine with standard timing....

Looking on line it turns out that ethanol is actually an octane booster and the petrol companies now produce a lower octane petrol specifically so that on mixing it with ethanol it gives the correct reading. Of course unfortunately for some engines it can bring other problems.....

I think you might be going overboard a bit. First of all higher octane in itself gives no more power but just allows the engine to run at the correct ignition timing without excessive pinking (pinging, knocking etc). This is optimum if a correctly running engine stops pinking on reaching 2000rpm when under full acceleration in 4th gear on the flat (air temperature will have an effect so best to do the test on the hottest day) and all you need is a fuel/additive that achieves this, any more is unnecessary. Note that valve seat recession is another matter that can occur with or without pinking taking place so other measures may be needed to prevent it.

but its a no brainer if as most people find 95 gives pinking but they want to maintain standard timing then instead of going to 97 use an octane booster + lead additive which works out cheaper per litre fuel and additionally gives the possibility of avoiding VSR. The new concentrated 500L treatment container is convenient to use and although its valve protection is an unknown (it was certified in the tests however) I can confirm the immediate reduction in pinking it gives....

orrrrr use Millers VSPe at 5p a litre of fuel to up 95 to 97ron so that normal running can be maintained while protecting your valve seats and so (hopefully) the jam jar will not be needed.....

Dont think either of those received FBHVC endorsement as their list only shows Millers, Red lIne, Castrol and Tetra Boost. On longer high speed runs I use Millers lead/octane booster with 95 fuel in my Vitesse 2L as it runs better. Also I hope it protects my valves as they have been reground and I believe, for a period, suffered quite severe valve seat recession although this was probably due to running a weak mixture due to air leaks which have now been cured....

It sounds like with polybushes its not necessary to tighten the bolts on the ground cos, as has been indicated, the bushes rotate on the metal sleeves anyway.....

yes my originals are 50 years old and still going strong - no fancy colours and dont look very pretty but doing the job!

Certainly in the original bushes the metal tube was bonded to the rubber hence the recommendation not to finally tighten the bolts until the wheels are supporting the cars weight. Doing this the rubber has to twist less for the full movement of the suspension.....

hmmm not easy to adjust the spring. I take it youve not found any dirt? How about getting a drop of thin oil in the bearing between cup and magnet? At least you can test it easily unlike a speedo.....

I get this after draining the system and have to force the air out of the heater by opening and closing the heater valve a few times while driving.....

yes this article is quite good although its for a speedo: http://obswww.unige.ch/~wildif/cars/docs/Smith-jaeger_speedo_repair.pdf Looks like the coil spring can become weaker so allowing the instrument to read proportionally higher across the complete range or possibly a lack of lubrication in the bearing between the magnet and cup might have the same effect....

There is a permanent magnet that spins around driven by the cable and is mounted just above that brass worm gear in the photo. It spins very close to the thin metal inverted 'cup' on top of it which if you gently move will move the pointer. The distance between these two is obviously critical for the calibration of the instrument so excessive wear in the bearings will cause misreadings as will any dirt that causes contact between the two. Cleaning/lubing is worth trying but overhaul and calibration is really a specialist job....

The standard brakes wont feel like a modern cos they need more effort but then should still be pretty effective. As mentioned above I found the pads used makes a big difference....

yes when you look at the faster/heavier cars right up to the end of the eighties that used the type 16 calipers there cant be much wrong with them: TR6, Capri 2.8 turbo, MK3 Cortina and Granada incl Estate.....

If your going to use one of those economically priced radiators they seem to be fine except for the inlet connection which aligns very poorly with thermostat housing outlet. On a recent thread somebody went as far as having the pipe re-welded at the correct angle however I dont think Id go that far. My prefered option would be to cut off the angle and find a rubber pipe with a suitable bend to make the connection....

What width tyres have you got fitted Bob?

yes fraid your thread suffered a severe hijack but glad to hear the problem is resolved. Hopefully the gearbox will give many miles of good service but remember they do tend to be noisy (especially if the cover isnt very well soundproofed) which makes it difficult to tell when a real problem is developing so that you run the risk of not catching it in time and suffering major expensive damage. With my 2L Ive developed a 'kind as possible' gear changing technique, well techniques as its different for different gears and of course religiously keep the oil level topped up. This last point is critical as theres not much capacity to start with and then the oil seems to evaporate away😁 leaving a low level which is the quickest way to finish off the box.....