Anything and everything Herald. Talk about anything from the first 948s to the last 13/60s.

The Spitfire engine (FC3510HE) in my Herald seems to be causing me no end of problems when it come to tuning...however I should not blame the engine as I am sure it is me!

I have a mark II spitty engine in my 1200 Herald which is using the Herald's Lucas Distributor. I have set the timing to 13 degree's BTDC and the points gap 0.015 giving a dwell angle of 58.6 as indicated in the front section the workshop manual...later in the manual it says the timing should be 9 degree's BTDC and the points gap should be 0.02 giving a dwell angle of 36 degrees (assuming that the dwell angle is the closed period as on all the other pages of the manual!).

Can anyone confirm what the correct settings are? I ask because the car seems to be lacking power, I have balanced the carbs (SU HS2&195;&8218;&226;&8364;&8482;s) and have set the mixture level so the spark plugs come out nice and brown looking and the Colortune looks correct, and am running out of ideas!

Help please Nig

Many thanks in advance...
Matt

Matt,

After a bit of checking around, I find that the recomended static timing for the 1147 is 17degrees BTDC. However, I don't know how much I trust that, as for you points gap I think your first figure is the right one. I don't know if these figures differ from Herald to Spitfire though and if they do then that will be were the confusion is occuring.

I've alwasy found that getting the right timing is less of an exact science these days, as fuels are different but the engines aren't. There are two ways to find your optimum timing.

The first is to accellerate (on a flat road) from say 30 - 60 mph and time it (on stopwatch), then adjust by a degree and do it again. You'll either be slower or faster and can adjust the timing accordingly. Then as you adjust further you will find a 'peak' (fastest accelleration) and that is where you should 'lock' the timing off.

The other opition is to do the same thing but on a sloped road and listen for pinking, keep adjusting until you get only slight pinking and that is right.

Each will take a little while to find and include a bit of zooming up and down some B road somewhere. But I would get the carbs fully balanced and lixture adjusted first (which you seem to have already done).

Of course the final option is to get a rolling road to do it all for you - this will cost &163;&194;&163;&194;&163; but will be money well spent.

Cheers
NiG

Matthew, As you are using the Herald Dizzy then the Dwell Angle should be 60 deg (closed period) if the gap is set to 0.015. Bearing in mind the wear and tolerance involved 58.6 deg is not bad.

The Herald Lucas Dizzy has a max centrifugal advance of 20 deg on the crank. The Herald static timing figure is 15 deg BTDC.

Where as the Spitfire MkII Delco Dizzy has a Max centrifugal advance of 26 deg on the crank and the static timing figure is 17 deg BTDC.

So if you are running the engine on LRP or super un-leaded I would start with the timing set to 17 deg BTDC. Carry out a road test as Nigel has suggested advancing the ignition up until the engine starts to pink, then back it off to a point where the pinking stops.

In theory the best setting should be 20 deg BTDC but then we do not have 4 or 5 star leaded fuel these days.

Thanks

Dave

Hi Dave and Nigel

Many thanks for the advice, I set the initial timing to 17 deg and then proceeded to drive up and down a nice hill until it started to pink. The engine now idles quite happily, sounds smoother and does indeed have more power...reaching 85mph before I got too scared to go any further.

The only thing is, the timing now seems to be at 24 deg BTDC...is this an issue or can I put it down to the engine set-up and the fuel catalyst in the petrol tank!

Your opinions would be appreciated!!

Thanks once again

Matt

If the engine will start from cold and isn't pinking or knocking then I wouldn't worry too much. The unfortunate truth is that the timing marks on the pulley wheel are not exactly accurate.

All kinds of things can effect the corerct setting which is why the books only serve as a guide.

Compression ratio, fuel rating, additives, mixture settings.

Drive it for a while and do a plug test to see if there's anything going on that you don't know about. Specifically you should look for silver/black balls of metal (almost microscopic) on the plug insulation (can look brown) this is an indication of pinking (even though you may not hear it).

NiG
http://www.niginthecar.net
racing@tssc.org.uk

Hi Matt,
The fuel catalyst certainly won't have any bearing on your timing.... or anything else for that matter, they're just a con.
Cheers,
Bill.

With the state of the tune on your engine the BTDC does not sound to far out to me. If it is not pinking then all should be OK.

Thanks

Dave

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