Spark plug change

[Jalmarsson666]

Hey, I have an E30 with a built M20b25, it has M21 crank, m52b28 pistons, m50 rods. I haven't built it myself so I noticed a problem when I was going to change the plugs, I bought the usual plugs for m20b25 but when I took out the old plugs that were in it they were about 5mm shorter. Does anyone know if the original plugs that I bought will protrude too much and hit the pistons if I decide to use them?

[superj]

Look down into the hike and see how long the threads are

They are probably a bit long but you have to look

[digger]

please provide a photo of the two plugs side by side, it is not uncommon for people to use the non projected plug as the common variant happens to be colder heat range. i'd suggest that what was done.