3.5 Ignition Advance

Having just fitted an electronic ignition kit to my 3.5 V8 (SU carbs) and as I had the use of a rather nifty Snap-On timing strobe, I thought I would check the ignition advance right through the specified rev range. It appears my old dizzy (35D8 41317B) is not advancing as much as it should (see graph). After fitting the electronic ignition my engine now starts and runs brilliantly and is a pleasure to drive again, other than perhaps lacking the power I would expect from a high compression 3.5. I am currently running it on standard unleaded, but will try super unleaded on the next fill and see what difference that makes.
I would appreciate any constructive comments on what I would need to do to improve/correct the advance so I can get the most out of my V8?

I think you can get lighter springs for the bob weights. also check their not seized up. Best way to set a V8 base timing is to keep advancing it till the engine pinks then back it off till it stops pinking! Trust me it works! The timing makes can be way out. Tune it by ear its the only way!

Great, sounds a sensible idea I'll get the spanners out at the weekend and see if the bob weights are ok then move onto advancing the timing until she pinks, luckily I have a nice gentle hill nearby I can trundle up in 5th!

v8hotrodboy said:

I think you can get lighter springs for the bob weights.

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SimonBBC sorted me out with bob weight springs as I bent mine - it's easily done if you pull the rotor arm up and it is stuck. The whole shaft moves up and springs bend against the posts. Be careful!