bimmerboy

VVT 1.8 with bolt ons and MS3 with wideband. FAB9 COP kit with fresh Brisk plugs at start of season.

I had burned up a few wideband wires a couple track days ago but repaired them. Checked and re-installed plugs at that time.

Prior track day car was running hot, 215-220 on Longacre gauge. Decided to gut t'stat and got to 200 deg yesterday, an improvement!

All was well until a high rpm miss and overall bad performance happened yesterday (first day after gutting t'stat). Upon removal of spark plugs found cyl 1 and 2 spark plug tips were gone!

Was this failure started during the wide band wires burning up and then amplified during the hot running days? Installed previous Denso plugs and all is well but only have 2 sessions. One step colder plugs ordered Bosch 7956 (these should have removable tips and are one step colder) to try.

spark by D S, on Flickr

SpartanSV

I would lock timing with the MS and check with a timing light. Then post your timing table and tell us what fuel you're using.

LeoNA

Those are too hot of a plug. Any concerns with NGK plugs? As previously mentioned, check timing and post your timing table.

bimmerboy

To work with Fab9 coils, the tips need to be removable. Not many options. I ordered some Bosch 7956 plugs with the removable terminal that are 1 step colder. But not sure that will change much.

LeoNA

It is also odd that it's eroding the center electrode before the side wire. I personally would switch coils just on the fact that they require a removable term which has become less common. There is a champion plug that may work. Many are not fans of the champ, but they are still a supplier for F1 engines. I prefer NGK and Denso mainly because of their comprehensive catalog and the relatively easy to use nomenclature.


https://www.sparkplugs.com/champion-...ium-spark-plug

sixshooter

iTrader: (12)

Sell fap9 coils and buy a reputable set that works with normal plugs?

bimmerboy

To bring this to closure. TLDR: Fuel pump

With the help of a friend we checked timing, vacuum leaks, compared MS tables to known good ones and everything checked out. Checked fuel pressure at idle and revving while standing still, tested good. Turned EGO control all the way up to 50% and it helped except at the higher rpm's where it shot back up in to the 14s. Ordered DW100 and installed into a visually clean tank.

Now idle AFRs are around 13.9 and WOT AFRs are 12.2 ad values are repeatable and stable. Tune needs to be touched up, but very confident it was a dying pump along.

DNMakinson

iTrader: (3)

With MS3, you can have AFR warning and "shutdown".

DNM

bimmerboy

Yes, well, I'm very new to EFI. I'm learning about all the "protection" MS3 has to offer.