Thread: Plug reading
05-10-2015, 07:47 PM #1
So who's the expert on plug reading? These do not look bad to me but the rim color being so black as it is had me curious. Plugs in order cyl#1 thru 3 left to right. I'm idling at 13.5afr & 1150EGT...I then drop to 13.0 at 6k (boost) then taper down to 11.6 at wot of 8750 and EGT's are 1630-1650 so me thinks I have a decent tune. I did a little net search and found a doc on rim color being black is an indication of a rich idle...from my numbers I doubted this to be true so figured I'd check in here.
05-10-2015, 08:00 PM #2
Idle is identified on the top part of the porcelain, the base ring Can read your tuneup at wot but really the only true indicator of a wot tuneup is the bottom part of the porcelain which you can't see with the naked eye. You have a fairly rich tuneup. Plug reading is worthless though for the most part if the plugs have any amount of runtime on them
05-10-2015, 08:28 PM #3
Those EGT's sounded good to me and really would be afraid to go leaner..unless others think leaning out more is safe? I pulled the plugs because it's time to change them, then questioned my own ability to read them with the blackened rim.
Well I just had brain fart once you said "any amount of run time" and realized I've forgotten my whole logic with changing those plugs. When I store it for the winter I fog pretty good and first ride of the season I like to use the last years plugs to burn the crap off..then change them. I don't want a new set of plugs burning off fogging fluid...least it's my logic anyways. With that said reading those are worthless because of that. Sorry to have jumped the gun on this and just forgot.
05-10-2015, 08:45 PM #4
05-10-2015, 09:24 PM #5
2014 winter mods
1.) CNC ported head and valve train upgrade by Slow91, complete rebuilt engine
2.) ET 137+4, w/08 oiler mod
3.) Fizzle F1000
4.) Reflashed ecu, 9200limiter, mapped for 80's
5.) Solas 13/19r
6.) Riva rrfpr
7.) X shoe conversion, driveshaft
8.) Jim's closed loop plate
9.) R&D grate
10.) gutted stock waterbox
11.) opas block offs
12.) CMD/WB2 w/LCD-200 (o2 sensor in j-pipe)
2015 winter mods
1.) 08+ exhaust, mid pipe & Riva shorty waterbox (lol...I got the last one before discontinued)
2.) 2012 exhaust manifold, taped & milled down for new o2 sensor location, EGT taped in flange to head area.
3.) Extrude honed exhaust manifold
4.) Solas 15/20r
5.) Rear air seat intake mod (Courtesy of Danny)
6.) plumbed per 08 setup with exception of 15psi pressure relief setup before IC.
7.) Heat Exchanger
7.) Jim's open loop plate
8.) vts added
9.) Maxbore TB mod, 58.5mm
10.) Engine temp & IAT now monitored via piggyback harness off stock sensors to CMD/WB2 analog inputs, displayed on LCD-200.
Now after the 2014 mods list I gps'd at 75.5. After doing the 2015 winter mods list today I gps'd at 76.5...I'm stumped by a 1mph gain from all that. Especially seeing how I went from a 13/19r to a 15/20r and turning nearly the exact same rpms with all those new mods. That to me in itself doesn't add up, how do you spin that prop difference the exact same rpm and yield 1mph more? I honestly was hoping the 2015 mods would put me near 80...I was either dead wrong or I'm seriously missing something.
05-11-2015, 07:32 AM #6
Where are the crush washers for plugs 1 & 3?
05-11-2015, 08:00 AM #7
pull your idle back to 14.3-14.5 sloping to 13.5-13.7 by 4k. 13 by 6500 and a gentle slope to 11.9. Run 93 octane and you'll have a great running ski that saves gas when you're not hammering.
BTW 1mph gain on a motor that's getting weak is still impressive. Compression and leakdown test it.
05-11-2015, 08:49 AM #8
05-11-2015, 08:59 AM #9
I can trial out those number and see where it's at. I'm running 11.5-11.6 at 8750 and 1630-1650 EGT at wot...going 11.9 worries me being at or over 1700 so I might take baby steps on that. This motor was rebuilt last winter so I'd not consider it weak...30hrs on it. Compression test I'm going to do...nothing but a Snap-On gauge for accuracy.
05-11-2015, 09:13 AM #10
Snap on is good stuff. Empty your bank account out but good stuff. I ran that with my 137x4 and shoot for those numbers with my 68-140. I also run AV fuel though. Well a 50/50 with 93 lately. It is a safe tune in FL as I've setup a few different local guys running the 137 with those numbers.
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