With my mods in sig what spark plugs should I use and at what gap? Thanks for help

 

I think the NGK TR5's would be good. I run the TR6 for nitrous but the 5's are mainly for N/A motors and I believe they are 1 or 2 steps colder in heat range than stock.

 

I think you should go with a colder plug. I tried A LOT of combinations for my setup and found out that .035 was perfect! Pretty cold plug if you ask me but thats what worked the best. I tried .06,.055,.05,.045, then finally .035. I'm almost tempted to go hotter to .04

 

.35 is a good starting point. If you raised the CR any with a stock ignition you may want to go .30. If you have a near stock CR and an aftermarket ignition you may try .40 or .45

 

I raised the compression just a little and Im using stock ignition other than high output coil. Ill try ngk tr5 at .035 then. Thanks