i had a race this past weekend at LRP. on the first lap, there were some on track incidents which brought out double yellow and we were doing pace lap speed for about 8 minutes. then when the green flag drop, i car was misfiring like crazy. like it was hitting rev limit at 5k rpm but it was still accelerating slightly. check engine lit up on the dash. i stayed out and nurse the car slightly. then after a few lap, it cleared up and happened less and less and eventually went away. the engine light went away on the last lap. i pulled the code and it said engine misfire bank 2.

could it be because the ignition coils got hot from doing slow pace laps, not enough air going through the engine bay? then once we got moving at race pace, it cooled down. i was planning to get all new oem coil packs, plugs and wires when i do the new engine in a few months. or should i upgrade ignition coils to something else? not sure what's a reliable ignition setup that has been proven on track. i've learn my lesson with the Evo and stay with oem as much as i can.

 

I would suggest upgrading to the BHR ignition with the new engine. Even without tuning the dwells they are better then the oem coils.

 

Definitely sounds like heat. Definitely go BHR, ignition is the one component of these cars where stock is not best, especially for racing.
Rotor 2 coils are toward the back of the coil bank and get the least cooling air, so that adds up...

I wonder if it would do the same if you just drove around town on a hot day.

 

i was thinking of adding an air duct from the front of the car to the coils to help bring cool air to it. since its getting blasted by hot air from the radiator.

 

You can, but I'm not sure anyone has had to do that. It sounds to me like a coil is already worn out, and a little bit of heat pushed it over the edge, so you're on borrowed time there anyway.

 

well everything in the engine bay has 75k miles on it before i turned it into a race car. and has 4 race weekend since then.

 

Coils tend to die around the 20K mile mark. One of my OE rev B coils died before 10K. That led me to upgrade to the BHR offering. 30K miles and ~50 track days later, and they are still going strong with no misfires.