Header question for those who have them.

[Rmtt]

Just a quick question. Any header upgrade I've ever done always (especially on LS Engines) always involved running a slightly colder spark plug. It just made tuning so much more stable.

For those of you who went to catless longtubes like AA which I have, did you guys do this or just stick to the stock OEM recommended plug?

I will still have my secondaries although I'm still debating my set up from there back.

Thanks!

[desertman123]

Haven't heard anything about this, following for more info.

[MCShred]

Stuck with OEM plugs and haven't had any issues with them

[Rmtt]

I know when I was learning HP Tuners software and working with other guys who had been tuning for years....modifications such as increasing compression, headers which allow timing/fuel changes, use of alternate fuels, can alter the plug tip temperature, necessitating a colder plug.

Now with BMW tuning, I didn't know how much timing and/or fuel is added if at all when dyno tuning.

For all I know, none of this may even be addressed as its a completely different animal. I just wanted to be sure I wasn't short changing myself.

Never seen it mentioned, so apparently it isn't maybe even needed!

[desertman123]

He's a real busy guy, but contact hassmaschine. He's been tuning these DMEs for years (MSV70/80).

I do know these DMEs are target-based systems, always running in closed loop. So not much needs to get changed as far as fuel/timing: you adjust the (math) model of the engine the DME uses, target AFRs and the DME will adjust accordingly.