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Ignition Map


Belle400

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Hi Guys

Id like some help with a base ignition map, ive posted up what i currently have which is a guess and not dyno tuned. I plan to dyno tune it next year after the christmas period.

Its in a light Tvr so maybe a Range Rover map etc isnt that suitable, although i doubt they are much different.

Im running Speed Density.

This is one ive found that looked good but im having a hard time trying to understand how to turn it into a Map based one.

https://forums.lr4x4.com/topic/84065-rover-v8-39-ignition-map/

Any tips are much appreciated, car likes to idle around 14 degrees and from what ive read needs 32 degrees max. Im idling at around 45 Kpa.

I used to run it at 18 degrees idle on the old 14cux and to be honest the car loved it and throttle response was great, i used the full manifold vacuum method as the ported method was very erratic.(a popular Tvr modification)

I will post up my current igniton map below.

car has the 3.9 engine with nice heads, cam and intake work.

Thanks in advance.

 

Screenshot (10).png

Edited by Belle400
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The one in the link you've posted is awful. Your current map you've posted is much better thought out! 

Have you booked some proper time on the dyno or just a power run? If so, is it capable of running steady state (holding to a certain speed no matter how hard you boot it)? 

With a spark advance table, you want to start from the 100KPa line and work down the table from there. The RV8 wants a lot of advance to make best power, but that opens up the risk of detonation if you go too far. As a rule you want to get almost full advance (probably somewhere a shade under 30 degrees in your case) just before the rpm where peak torque occurs. Keep it stable through peak torque and smoothly add a, few more degrees up to redline. The 90 kpa line should look the same shape - maybe a degree more from peak torque onwards. The danger zone for detonation is the high load, low rpm - peak torque area, which is why you don't want to run much more advance - if any more at all - than in the idle area. The lower-load, medium to higher rpm areas you can afford to safely run more advance, and this helps get the most out of the less dense mixture which combusts more slowly. Hopefully you can see how all of this reflects in your current map. 

I'm short: your current table is solidly thought out. Try a couple more degrees, not forgetting to adjust the fueling. Look at the power developed. If you're not making much more power, there's no advantage to running more advance and you're at the optimum level. Listen for pinging. It sounds like gravel being flung from a tyre into a metal wheel arch and will give spikes on the dyno plot. Back off the advance and add a little fuel if you find a problem area. 

Good luck! 

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