Re: A question regarding ignition timing

Mungo Jerry wrote: Snips

If I advance the timing on my car, it gives much better acceleration.

It'll give better acceleration, but you may be burning the pistons/valves by running the ignition advanced.

Will this affect the top speed also ? Should the car be "faster" ? > I know the timing should be set with a light etc and I`ve tried that as have > a local garage but the end result was either a distinct lack of power OR > power with "pinking".

Pinking (pre-ignition) is the ignition advanced too far. If it is retarded, it will give slower acceleration,but will not pink, and will run cooler. Pinking is not a good thing.The cylinders will be getting hotter than normal, and in the worst case, a hole(s) will be burnt in the piston.

> The garage suggested I set the timing using the "trial & error" method! I`ve > done so and have got the pinking down to a minimum (just a split second of > it if I change up and accelerate hard immediately).

It shouldnt be pinking at all.You may need a decoke.If the head has never been off on a 10yo car, then I think that would be a certain part of the pinking. Also, it may pay to get a 'cooler' (or is is hotter?) set of plugs.I had this a few years ago with a motorbike - it would always 'pink' with the recommended plugs, but once a cooler set were fitted, it was fine.

But I noticed today that the top speed seems to have reduced slightly. Now I > suppose this could be down to the fact that a new aux-shaft oil seal has > increased the oil pressure - but I just don`t know! (previously, the oil was > really pouring out of this - the garage said that the seal was just hanging > on the shaft)

I cant see how a leaking oil seal would affect the top/any speed at all.What is a aux-shaft?

> I`m tempted to have another twiddle with the distributor - but just thought > I`d ask for some opinions here.

Yes, turn it just a little toward TDC, to try to get rid of the pinking.Buy a strobe light and see what it says.If the ignition advance is retarded more than it should be, and it is still pinking, then you'll need to do a decoke to cure it. A DIY decoke shouldnt cost more than £100 for the gaskets and fluids.

Alan.