Hi everyone,

I am looking for some feedback on my current ignition table before I continue tuning the car further.

I know it is not possible to properly optimise ignition timing without dyno time and knock detection, but I would like to build a reasonably safe and usable base ignition table based on other people’s experience with similar MX5 / BP4W supercharged setups. The plan is to use this only for a few weeks until I can get the car on a dyno. I am not trying to tune for maximum power on the road. I only want a bit more "spicy" temporary ignition map so I can continue sorting out the rest of the setup before taking the car to a dyno.

The car is a Mazda MX5 NB with the 1.8 BP4W engine. The engine is currently stock internally. My supercharger makes around 7.5 PSI boost.

Current setup:

- Link G4X ECU
- FIC 525cc injectors
- Walbro 255 LPH fuel pump
- AEM wideband controller with Bosch wideband sensor
- Eaton M45 supercharger
- 15% reduced supercharger pulley
- Dual throttle body setup
- Larger intercooler
- M2 aluminium radiator

I have attached the ignition table I am considering using.

My goal is not to create an aggressive “maximum power” table without dyno tuning, but I would like something a little stronger than a very conservative base map, while still being reliable enough for light road use until the dyno session.

Could you please have a look at the attached ignition table and let me know:

- Does this table look generally reasonable for a supercharged BP4W engine?
- Are there any areas that look too aggressive or unsafe?
- Are the higher load / boost areas too advanced?
- Would you reduce timing anywhere before driving the car?
- Does the off-boost / cruise area look sensible?
- Is there anything obvious I should change before using this as a temporary base table?

I will be keeping AFR safe and monitoring the car carefully. I understand that final ignition timing should be set properly on a dyno, but I would really appreciate any advice from people who have tuned or run similar M45 / BP4W setups.

Thank you.

MX5 MK2 NB1 Ignition table

 

You got some great feedback on the Link forum, although I'll add to that that you should linearly interpolate from your 100kpa to 200kpa row.

And although Adamw doesn't know BP's, he's pretty close, although you could edge closer to 28 in the 100kpa row, then make sure you lose ~1*/psi. 200kpa is 14.5psi, so you should be around 14 degrees, but it'd be safer to end closer to 12 like the table you posted on the Link forum. I just don't like how some rows don't change, like 140 to 150kpa.

 

Hello curly,

Yeah I got few really good feedback from Adamw, so I adjusted a bit my ignition table. Also I tried to follow your advice.

Is there anything else which should be adjusted on this ignition talbe? Or is it would be a good enough? I try to find something which I can use before my dyno session.

 

No, I’d say that looks ok, especially if you’re headed to the dyno. You may find a different timing curve is better, it’s a little weird to peak and then lower towards redline, but superchargers are weird anyways.