Vehicle: 1990 Maazda MX-5/Miata
Engine: 1.8l 99-00 NB engine with CAI, full exhaust and soon to have lumpy cams.
Injection: Port, alternating, stock 230cc injectors.
Description: Fuel, spark and idle control using MSnS-E 29h and MegaTune 2.25.
My Miata/MX has recently had an NB8A engine fitted and while that was being done I upgraded my MS (which had been running fuel on the 1.6) to also run spark and idle control for the 1.8. I used the CAS board upgrade as described on the diyautotune site which works for a Miata CAS as well as the Toyota 4ag. The ignition mods were borrowed from Nate Sullieâ€™s success story.
The VE table was generated using MegaTune, the spark advance table was sourced from a FM Link table and then modified for the 12 x 12 MS spark tables, and the idle settings were used from a post on the MS EFI forum also by NateSully.
The car literally started at the first attempt. I mucked around with the idle screw for 30 seconds to stabilise the idle between 840 - 860 rpm and it happily drove around the block without any problems other than a bit of adjustment being needed for the acceleration settings.
I'm just amazed that the MS is working so well with the spark and idle given that all I've done is a few board mods based on some forum posts, and expanded and guestimated a spark table from a FM link spark table. I admit that it's nowhere near being properly tuned but for it to be behaving this well straight away has simply stunned me.
After taking the car for a 30 min drive and it is almost as good as the OEM setup without any tuning what-so-ever. If it's this good already, I can't wait until I start tuning it!!!