Exhaust Temps

Modman

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Matt, here is a quote I posted from another thread. The links give some really good information on plug reading and EGT baseline correlation. They are much more comprehensive than what I would post here.

If you need more info, search "plug reading" on the forum here and you will find more info.
Hope that helps.
Koso makes an A/F gauge that I have been using, seems to work OK. Koso's displays are some of the best for "readability" (compared to some others like autometer) but they are quite a bit more expensive.

I think you meant 14.7:1 ratio. Yes, they are good for tuning, better for tuning than an EGT IMO, A/F ratio is a more scientific approach than EGT's since it is less likely to be influenced by engine factors and probe placement (EGT's are more prone to this than A/F), less "false positives".

As stated, always confirm with plug and wash reading. Once you have determined the baseline settings for your sled, your EGT and A/F readings are relative to the baseline setting and are your reference point for knowing where the max values are.

Here is a good read on baseline setting
DigatronTech

Some good plug reading tips and photos

Piston Reading
Plug Reading Spark Plugs
SparkPlugs
[media]http://tsrsoftware.com/images[/media]
 

imdoo'n

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Flange face on my sled is about 2" from the piston, getting close if you are 4" from the flange (probably close to 6" from exhaust face). You're probably not wrong and so long as its' correlated to plug colour, its just a reference point. Probe palcement seems to mainly depend on style of pipe and where the flame peak occurs, so yes, sled specific. Twin probes in a single "Y" pipe have to be about 2" from the "Y" join at the pipe junction so they are as far out as possible but not so far out so the cylinders do not interfere with one another, single probe in a "Y" they usually say put it right at the "Y" right in front of the pipe junction (this would be 2" farther from the twin probes in a "Y") and for twins/triple pipes its pretty standard on 18-12" out from piston face.

This is where mine are in both sleds and they are bang on correlated to plug colour, slightly darker on the twins which is why I run to about 1350 with it. The triple is max 1320, I usually shut it down about 1280 because it is almost perfect tan at 1250, shows light gray and white at 1300+.

I know a 1085 Polaris that runs at 1350-1380 though, this is a perfect tan on that motor, twin pipes and 10" from the piston face. This sled is running 100% AV gas though so fuel burn will be a little farther down the pipe.

Not sayin' my word is law, that's just my experience from my #'s. Everybody's gotta make their own.

you the master:bow: and when it comes to giving me the sheet your the best. Merry Christmas bud.
 

1100

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You should be able to download boondocker box instructions somewhere off the net. When the box is at all zeros this is the stock fuel settings your stock M 7 would be running, seeing you have a big bore I would assume your going to be positive on all your numbers, When you do a plug check and verify that you are running lean you will want to add fuel in that RPM range.

The box has a low, mid, and high setting for each RPM range. The high will affect the top end in the upper RPM ranges, but if you change the high in the lower RPM ranges, it will take and control how much fuel the injectors are dumping when you grab a handful of throttle.

The mid will affect your cruising RPM (1/3-3/4) throttle. This is the one you will more than likely have to add fuel on.

The low setting on the box will control your Idle at the lowest RPM range, and then your (o-1/3) throttle setting up to about 4000 RPM. When you add onto the low fuel setting on the upper RPM ranges it gives fuel after u let off the gas.
 

MattM

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Hey guys thanks to everyone for the posts and the help! Got to tinkering here in my last set off and found that playing with the low and midrange numbers in the boone box didn’t do a dang thing. Sooo after a little more research I found some codes coming up on the box that suggested a wiring problem after getting that all straightened out I found it very easy to tune the box into the exhaust temps and checked the plugs looks like I'm getting things at least headed in the right direction if not perfect.:d AGAIN thanks fellas hope to ride in the mountains soon!


Matt
 
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