koso and a/f gauge

[Dummy]

Iam running both the koso and a/f gauge at full throttle the koso is reading 1250 and the a/f is reading 10.1 which one do you rely on?I turned up the fuel pressure to bring down the egt's because no matter what I did to the fuel box I had really high temps(1375-1420)thats what the koso was saying,so know when I hold it to the bars itstarts to bog so I know it is overfueling.Any fixs out there?
It,s on a 09 M8boondocker race gas setup.

 

[BigAir]

Need more info. So you have Koso EGTs, but what brand of A/F gauge? How old is the sensor? What fuel pressure and box numbers are you running? Exhaust temps will vary A LOT depending how far away from the piston the probes are mounted. How far away from the piston skirt are the probes mounted?

 

[MAINJET]

If your guages are both in good working order i would use the A/F guage. Then when you have that where you want it use the temp on your EGT's as a baseline and then remove the O2 as they are supposed to foul rather quickly. I am having the same problem with my egt's. In fact I had the same problem with the last set of egt's I ran. They both seemed to run too high. Then when I made adjustments to bring down the temps the engine was running extremely rich. Just my opinion. I am considering buying an O2 but have concerns that it wont be any more reliable than the EGT's.

 

[mountain_tamer]

If you are too rich your EGT's will read high as a result from the fuel being burned in the pipe.

If you are at 10.5 on your a/f you are rich and that will be the reason you have high EGT's if you lean out your sled I bet you will see lower EGT's for sure.

 

[Dummy]

a/f gauge

It is a AEM UEGo wideband #30-4100 it is brand new.My fuel pressure is at 44lbs any lower and my temps go high.I do not have ada on my box so i have a bunch of different # it is a older boondocker box its off of a 07 m8t I tried a newer box on saturday and it made it about a mile and would shut down like it was running out of fuel I had to keep turning the fuel pressure up to 62lbs to get it to start so i went back to the old Box.

 

[Dummy]

a/f

I thought the lower the # on the a/f gauge the leaner it is?Don't you want to run around 12.2?

 

[WyoBoy1000]

12.8 on the A/F, don't let it get above that for very long. 13 is to lean at wot. But you will see 14-15 in the mid range. the AF only works when at WOT. Just use the A/F for now and see what happens, I would run it around 12.2-12.5 for now and it should run good. But I would also make a hard 5 sec pull, and check plugs. You have to hit the kill switch when you are still at WOT if you let off it will change the readings (or as soon as you can after the pull)

 

[Dummy]

a/f

Thanks I thought for some reason that the lower the # the leaner it was.that explains it

 

[christian]

next time pull your plugs

 

[WyoBoy1000]

maybe check with BD on the A/F reading you want. If your under 12.5 you should be good, I just don't want to cause you a problem.

 

[Dummy]

Plugs

It takes to long to pull the plugs,the sled has to cool down because it burns my hands and my jacket and I run avgas it is about impossible to read the plugs because it turns them yellow.

 

[harf69]

to do a plug check you really need to be wfo for 1/4 mile to be accurate id try to set it around 11.8-12.2 you will get good power and and have a safe zone for the cold mornings the aem works well ive been using them for a few years they will get lead fouled over time

 

[WyoBoy1000]

FYI sometimes mine will load up under 12, sometimes it pulls hard at 11.8 less than that and it wont hit rpm

 

[harf69]

thats wierd im running a ovs tial rg 08 m8 ive got a friend that has a pump ovs kit 09 m8 we have had really good power and luck at 11.8-12.2 i dont know if its because its the older sleds or what.With the aem guage everyone told me to tune to 12 at the most.A friend of mine is running the bd pg kit with ebc on a 2011 m8 at 6lbs its a little rocket he has his egt at 1100-1150
i told him he could lean it out he said its making great power and a set of plugs is cheaper than a top end i said good point that is what has worked for us