Roger King

Bob, your photo of the "cotton reel" bobbins looks about right. I'm afraid this isn't an exact science because the steel cups are not made to a precise and consistent dimension. Miker7's description is about right re. the amount you can move the carbs up and down at the air filter end so long as this is done without exerting significant force (yes I know that's really vague). Tiny air leaks are an absolute no-no at idle, but will have no significant effect at full throttle. What you can do is to spray WD40 or similar over the Misabs when the engine is idling. If it makes a noticeable change to the idle speed or smoothness that suggests a leak (which the spray has temporarily sealed).

Yes, that's a common failure with Supersprint Crossflows as well, due to using 1300ccm pistons designed for 50bhp in a (claimed) 135bhp application revving much higher than standard.

Yes, Oily is correct, the carbs need a certain amount of flexibility on the inlet manifold, but not so much that you end up with an air leak at the carb/manifold joint. What engine do you have? If it's a Supersprint Crossflow, they very often pop, splutter and behave nastily on very light throttle. If that is what you have (and only if) the solution is usually to change the 45F9 idle jets to 50F9. In affected cars this make a dramatic difference. If it's not a Supersprint, ignore the above jetting advice.

Not a guaranteed solution, but check the float levels are correct and the fuel pressure isn't too high (3psi max). And also the condition of the needle valves.

In similar vein I fitted a wind breaker to my Frogeye. Unfortunately, when we get home she complains about the difficulty of getting out of such a low car.

Dikko, as the owner of an actual Sprite (Frogeye) with a dynamo, I can only say that I have never had any issues with charging. The difference is that I have a mechanical fuel pump and contact breakers, but I suspect that won't make too much difference. I assume you are not driving this "strange" car to events so my view is that you are unlikely to have problems, particularly if you fully the charge the battery before events. This does of course assume that what you have is functioning well at present. One thing I have heard of - but never had to verify for myself - is that because dynamo casings have little in the way of venting compared to an alternator, overheating problems can arise with a dynamator.

I believe the reason for the cam change was cost - no cam to pay for, no engine strip down labour required.

I successfully honed the leaking wheel cylinders from my Austin Healey around 40 years ago. I used a flexhone for the job and with a new set of seals they worked perfectly. As others have said it all depends on there being no pitting. Mind you, it worked for me, but I've no idea if it's recommended practice; I only build engines.

A Sprint should come in one of two specifications. Later ones came bog standard as supplied by Ford, but with 2 x 40DCOE carbs, and earlier ones, the same but with an A2 camshaft fitted.

Unless this is a race engine with an expected limited life, I'd rather see the CR nearer 11:1. However, without knowing more about the engine that can only be a guesstimate. Whatever, you must use the highest octane fuel you can get. Regarding the Accralites - unless they've changed since I last used a set they are really excellent and use one of the lowest friction and best sealing ring packs available, but I always had to enlarge the valve pocket diameters if I was going for something like 1.625" inlet valves and 1.375" exhaust valves. They were fine with standard valve sizes.

Yes, you should be able to rock them by hand. I don't know which pistons you have, and it's 20 years since I last built an engine, but many of the pistons available in my day (even forged ones) had valve pockets that would need opening out if you were using larger than standard valves. Generally, the forged pistons have deep enough valve pockets to cater for longer duration, higher lift cam profiles, but you should always check piston/valve clearance unless the engine is completely standard. On my build sheets I always noted that figure, not so much because I might need the information for future reference, but because it ensured I checked it. Do you know the compression ratio? I would generally expect it to be in the range 10:1 to 11.6:1 depending on the engine spec and use. The lower figure would be for a mild road engine on 40DCOEs and the latter for a full race engine. There can be exceptions, such as supercharged and turbocharged engines.

Are you certain of this? A cold engine will have a large (.030"ish) piston to bore clearance which means they can rock considerably and the piston deck height can be "adjusted" simply by pushing them from side to side. If it's for real, I would most certainly be having a discussion with the builder. It may run, but it ain't right. However, the mere fact that you have piston/valve contact suggests some serious competence issues. You may now have slightly bent valves, and even if not, I would insist on them being replaced in case one of them decides to part company with its head.

Assuming it is low speed running that you are having problems with, then a standard GT cam should sort the problem. A 32/36 should run just fine with that. And definitely do fit a vac advance if you go for that combo. It is the old fashioned, and rather cruder, equivalent of 3D mapped ignition and will improve both economy and part throttle performance quite considerably. Sadly though, it doesn't really work with DCOEs because they lead to a strongly pulsing vacuum signal in the hose which can send the dizzy into spasms.

To be honest, I don't have the jetting for this, but from my experience you are likely to have problems with this carb/cam combination, particularly at idle and light throttle. The problem is that the A2 is relatively long duration and doesn't draw much air at idle which requires the throttle butterfly to be open more than a standard cam would. Unfortunately, this positions the butterfly beyond the idle jet and progression holes so that fuelling is very poor at this point. Once you get enough throttle and revs to get onto the main jet it normally runs OK. I have to declare that I don't have a lot of experience of this so I could be wrong, but this was my diagnosis the one time we tried this combination. Eventually, we fitted a pair of 40DCOEs and the engine was as sweet as a nut.

This is a constant energy system which means that the coil is a special part with low resistance so that it can charge very quickly. I've never tried running a standard type coil with this system but I expect there will be issues.