Ignition advance

[chj]

Could anyone advise me as to roughly what ignition advance I should expect at top end. Is 30degrees enough? Thanks,

Chris
420SEAC

[chj]

B-Reight said:

Chris, The 'How to Powertune the Rover V8' states MAXIMUM of;

3.5 - 36 degrees
3.9 - 34
4.2 - 30
4.5+ 28

On my 390 there was no additional power measurable above 29 degrees all in, but it was possible to fatten up the torque curve at lower rpms by bringing more advance in earlier.

Excellent, thank you . Currently maxing out at just 22 degrees, so expect there is quite a bit more power to come when adjusted properly

[cuneus]

Chris those figures are for total advance so made up of static/idle advance and mechanical advance

How is the 22 degrees being measured ?

[chj]

cuneus said:

Chris those figures are for total advance so made up of static/idle advance and mechanical advance

How is the 22 degrees being measured ?

Hi David

I believe it is total advance which is being reached at approx 2500rpm - there is no more advance at all after that. I dropped the car off at the classic Jag race engineers that are near to where I work, mainly for them to check/adjust the geo. I also asked them to check the mixture if they had time, as I thought that the engine was running lean and the MOT emmissions were only 0.7%CO as you know. Luckily they put the car on the dyno and found that the engine was running way too lean at all rpm. They adjusted that across the range to "something half-sensible" (as they put it), but they also picked up on the ignition advance. They are extremely busy at the moment and needed the space in the workshop overnight so left it as it is, but would like the car back a bit later in the year. They suggested somewhere around 30 to 35 degrees total advance would be what they would expect to see, hence my question, in case it might help.

The richening of the mixture has made a big difference already. Initially on buying the car I thought it was not really all that different overall to the 400 acceleration wise - it is now much more rapid ... a completely different animal altogether. I am really quite excited to see what it is like when they have spent another hour or two with it.

Cheers,

Chris

[cuneus]

That's great news (won't be needing the Mark Adams appointment from 2009!)