[thevinman01]

Ever since I got the car I haven't changed the spark plugs. and it has been about 33000 miles. Is it okay to go with 2 steps colder spark plugs for Stage 2 or should I go with 1 step colder and what gap size?

Also, is it possible for flames to shoot with new spark plugs?

BM3 stage 2 (agg)/ Bms intake/ Vrsf catless Dp

[Efftooto]

Not sure about flames, or which plug to use. But I wouldn't flash Stage 2 without a new FMIC and Charge Pipe added to your mod list first. Charge Pipe the most crucial.

Chris

[Tomskeed]

Originally Posted by Efftooto

Not sure about flames, or which plug to use. But I wouldn't flash Stage 2 without a new FMIC and Charge Pipe added to your mod list first. Charge Pipe the most crucial.

Chris

^100% this! These things blow the charge pipe all the time, even under stock boost. Change it now and avoid limping it home or a flatbed later.

To your original question, they have recommendations on BM3's site: https://bootmod3.atlassian.net/wiki/...+and+which+gap

I used the NGK SILZKBR8D8S (97506) gapped at .022

[OldCrow7xx]

Originally Posted by Tomskeed

^100% this! These things blow the charge pipe all the time, even under stock boost. Change it now and avoid limping it home or a flatbed later.

To your original question, they have recommendations on BM3's site: https://bootmod3.atlassian.net/wiki/spaces/BCS/pages/2558945/BMW+F+series+N20+N55+S55+S63TU+Spark+Plugs+-+What+brand+and+which+gap

I used the NGK SILZKBR8D8S (97506) gapped at .022

What does colder and gapping mean? Always wondered why people change these out.

[Tomskeed]

Originally Posted by OldCrow7xx

What does colder and gapping mean? Always wondered why people change these out.

"Gapping" would be manipulating the distance between the center electrode (the top of the inside portion of the spark plug) and the ground electrode (that L-shaped metal on the end). That gap of air is where the voltage jumps to create the actual spark. The gap determines the strength of the spark, more or less.

"Colder" plugs reference the spark plugs ability to dissipate heat and keep the temps down in the cylinder, preventing knock, pre-detonation, spark plug tips melting, etc. Most recommendations are one step colder plugs for every 75-100 horsepower you add over stock, or if you're changing the air/fuel ratio up for some reason.

[OldCrow7xx]

Originally Posted by Tomskeed

"Gapping" would be manipulating the distance between the center electrode (the top of the inside portion of the spark plug) and the ground electrode (that L-shaped metal on the end). That gap of air is where the voltage jumps to create the actual spark. The gap determines the strength of the spark, more or less.

"Colder" plugs reference the spark plugs ability to dissipate heat and keep the temps down in the cylinder, preventing knock, pre-detonation, spark plug tips melting, etc. Most recommendations are one step colder plugs for every 75-100 horsepower you add over stock, or if you're changing the air/fuel ratio up for some reason.

Wow thats super helpful, thank you