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Crazy load values on EVO X

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Hey guys,

I'm trying to tune a buddy's EVO X which has recently had the turbo upgraded together with forged rods and pistons.

The intake system on the car is completely stock.

When I log load from the stock ecu I am seeing really crazy values, in the 1000's range which makes no sense.

Would the MAF sensor need to be re-scaled in a situation like this and can be causing the issue? Any feed back would be appreciated, thanks.

If the intake system has been modified then yes, it may be necessary to rescale the MAF, however what your explaining sounds pretty extreme. I haven't had much to do with EVO X tuning however I've done plenty with the earlier EVOs and never seen load in the thousands. It's a common mistake to assume that the load value is a representation of manifold pressure in kPA - For example 100% load = 100 kPa. This actually isn't the case but it does usually correlate quite closely and that's the sort of values you could expect. ie if you're seeing 250 kPa boost pressure, the load would typically be in the range of 250% +/- about 20%. The load however will vary with air density and hence you may see the load vs boost pressure vary a little from hot to cold conditions.

I would be checking all the changes that have been made and confirming that everything has been properly accounted for. Did you happen to tune or log this ECU prior to the turbo upgrade? Is the load reading stable or is it erratic?


The intake system is completely stock still, the only thing that has been changed is the turbo charger and the engine has been fitted with forged rods and pistons.

I did not log the load parameters before the upgrades.

The waste gate duty cycle is completely zero'd out at the moment hence its running on spring pressure. I am seeing 18psi boost from an aftermarket boost gauge. The boost is holding pretty steady at 18psi throughout the rev range at wot. I will check and see what the load value is doing.

Hi, have you tuned an Evo X before? I am thinking you are not logging the right load value as those values are way out even for a car with a crazy boost leak.

Never tuned one before so it is very possible I am doing something wrong.

I am looking at the only load values I see on the evo scan logging software

Are you using Mode 23 for logging? The regular CAN logging is not suitable. Many inaccurate values.

No I am using the CAN logging. So then I should switch to mode 23?

I assume you have done this on evo x's in jamaica? Are the ones over there JDM imports from japan as well?

The one I am working on is a 2009 JDM GSR manual version.


Yup, have done a few out here. All JDM.

Yes, you should use mode 23 logging, but you will have to modify your ROM for it to work. Under the misc. section you should see three single value Mode 23 tables. The first two you should change the values from 5 to 23 and the third from 42 to 52. Then select Mode 23 in Evoscan for the model Evo X you are using.

Thanks a lot man, I will try that and see how it goes.

I have a couple other questions that maybe you can answer, just found you guys' page on fb....will hit you a message there.