Slant 6 Turbo 68Dart Project
got me thinking about this now. might have to open up the gap on my plugs and see what happens. wondering if it might help with what i got going on at cruise.
Jr, let me tell you, gapping those plugs open a bit - the difference is night and day, I was obviously not burning everything - the car doesn't smell like gas anymore, and the idle was way smoother. It even drives a hell of a lot quieter and everything - is just - night and day - totally, but I'm also running low boost, so this may be a safer option for me. Remember the gap is amplified by the amount of pressure in the cylinder, but i think even at a 20psi increase it's not going to effect it too hard.
Everyone on sl6.org suggests somehwere in the .040 + range for a stock slant, and that's what the engine guy at the shop said if you have electronic ignition. Everyone with a turbo has it gapped to .028 - .030 or something like that. I've found that .035 is kind of centered to what is being said, so I went with as close to that as I could bend. If you have a MSD or HEI I'm sure your ignition system can handle the distance. I'm thinking the problem with the gap and turbos is when the pressure is too high, the distance needing to be covered exceeds the voltage of your coil, therfor you have a misfire under higher load.
It can't really be a temp issue I think because I'm running the stock engine - 1 step colder plugs, and there is no overheat, and the car just sounds better - audibly.
Granted - this may be an isolated incident and my setup just wants a bigger gap, but we'll see. Driving around today I had no issue getting up to 8psi smoothly and the car even starts the first time now and stays running in the morning. The idle speed was also way higher once I did that and ran with a lot less stumbling when cold - had to turn the idle screws down.