Spark Plugs on modded 16v

[apardal]

Hi!

I've been wondering which spark plugs would suit best my engine setup as I'm having some trouble starting the engine cold.

If I use NGK's Heat 6 standard spark plugs (BCPR6ES) the engine will have an easy start but when hot it will eventually start to fail at high revs.

So I've tried a number of different spark plugs (different heat 6 and heat 7) ending with BCPR9ES (Heat 9) spark plugs to get it running properly when hot.

As time goes by, I'm gradually finding it harder to start the engine cold.

I know I may have some cold start tuning on megasquirt to do, but I think the spark plugs will have a say on it too.

What do you think?

This is my setup:

-Blue Top 4A-GE
-Wiseco Pistons 81.5
-Kent Cams 298º duration and 9.4mm lift
-Shimless lifters
-Slightly ported and polished head
-Compression Ratio 12:1
-Silvertop AE101 ITB's
-Tsudo Exhaust headers with 2.25" pipe with mid muffler and final muffler (Apexi WS Universal)
-Megasquirt V2.2
-Rev Limit 8900rpm
-Dynoed with 170hp@8100 and 160Nm@6700