K
krikra
Guest
Took out the plugs. #1 was black. Not weat but soothy.. The other 3 plugs are whiteish. Looks like that cyl #1 is runnng quite a bit richer than the other 3??? Car drives perfect.. No problems at all. But still concerned about this plug colour thing..
The engine is a fresh fresh built engine. Arias pistons, Crower rods, Cometic HG, ARP bolts in both ends. Only just run in and about to start tuning it.. Need to get this solved before I go for any high numbers though!
Compression is even across all 4.
The injectors are almost new MSD #72's. Just had them flow tested before they went in. Fuel rail is uprated. SARD FPR set to standard fuel pressure. SARD fuel pump. AEM EMS.
AFR is fine (11,5) but that could be averaging out the rich #1 and with the other 3???
Ignition map is conservative. Not getting any knock.
First I thought it might be a bad plug so switched over plug #1 and #4.
This didnt cure the problem. Still #1 got black
I checked the leads and changed the rotor and distributor for new ones.
The problem is still present but looks a little more even now when looking at the 4 plugs. #1 is brown so still a litttle rich. #2 is very little brown #3 white #4 white....
Need some ideas.. What to try next?
HG leak?
Valve problem?
The engine is a fresh fresh built engine. Arias pistons, Crower rods, Cometic HG, ARP bolts in both ends. Only just run in and about to start tuning it.. Need to get this solved before I go for any high numbers though!
Compression is even across all 4.
The injectors are almost new MSD #72's. Just had them flow tested before they went in. Fuel rail is uprated. SARD FPR set to standard fuel pressure. SARD fuel pump. AEM EMS.
AFR is fine (11,5) but that could be averaging out the rich #1 and with the other 3???
Ignition map is conservative. Not getting any knock.
First I thought it might be a bad plug so switched over plug #1 and #4.
This didnt cure the problem. Still #1 got black
I checked the leads and changed the rotor and distributor for new ones.
The problem is still present but looks a little more even now when looking at the 4 plugs. #1 is brown so still a litttle rich. #2 is very little brown #3 white #4 white....
Need some ideas.. What to try next?
HG leak?
Valve problem?
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