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Hey fellas, just got a new engine finished. Would like some opinions on these plugs. To me they look good, but I'm not a expert at reading plugs. Wanna know if these plugs look like some timing can be added. Thanks

Engine: 10:1 Teksid 2V Mod Motor. TFS heads, stg 4 MHS Turbo cams.

13* Timing on the top end @ 18 psi.
E85 fuel, but was only at 73% Ethanol due to some 93 was mixed with it.
IAT temp was 118* at 7k rpm
11.4- 11.5 AFR on gas scale.
 

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It’s kind of hard to tell from the pics. They look good to me but as low as the timing sounds to me not knowing mod motors, they don’t look like I would put any more timing in them if it were me.
 

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It’s kind of hard to tell from the pics. They look good to me but as low as the timing sounds to me not knowing mod motors, they don’t look like I would put any more timing in them if it were me.
Yea this is my first mod motor. I built my timing map super conservative, and the plugs look real good right out of the gate. Wtf?
My last engine was a windsor 363 AFR 225s, F1R, C16, no intercooler, and liked 27* total...lmao
 

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EFI ?
Where is the IAT measured?
What was the ambient temp for the plugs above? IAT is going to follow ambient so the delta T for the plug pix is going to pretty much stay the the same which means it'll go up 30* when the ambient goes up 30*.
You state "conservative timing" but that is kinda relative. If the plugs represent WOT chops then as Dave mentioned, WOT timing pretty much there.

The AFR/Lambda data you posted is reasonable for IAT being under control.
The AFR numbers are relative to IAT - lower IAT, the leaner you can go with respect to the fuel type and where the fuel is introduced - port injector, blow-through, etc.
Once IATs get over 145F, you may need to add fuel or take out timing or both to prevent detonation, or introduce water/meth to help out the intercooler. 145F is the number I used for other turbo/intercooled stuff when developing a 4 stroke package a while ago but it had to be real conservative to keep customers from wrecking stuff. It also happens to be the IAT where medium duty diesels start to derate so there is more than just my word behind the IAT number. There are probably many examples of folks running hotter IAT with no detrimental side effects but this is just my experience. You have experience with your previous procharged hotrod so you have a good background on charged engines.

YMMV.
 

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Imo some of those ratios are rich. Of course every combo is different. On gas scale I idle around 14:1, cruise 14.7, 0 vac 12.5, and 11ish at 15lbs. I have had very good luck with. Just my .02.
 
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