Hi guys,
As the temps are getting colder, a few XEDE owners have reported hitting their boost/maf cut in the higher gears under full boost. These folks will need to reduce their boost a tad. Just 1/2psi will do it. Of course, it is recommended that one has a boost gauge before trying this.

The instructions (with pictures!) for doing such a thing can be found at:

https://www.evolutionm.net/forums/sh...threadid=44342

Regards,
Shiv

 

how about posting a new map with these new adjustments ? maybe call it stage one(or zero) cold weather map ?

 

I can certainly do that. However, the map database is going to get awfully crowded. I'll get to it later this week and see if I can do some housekeeping to make things better organized.

Cheers,
shiv

 

Any way to make it sensor-driven (for example) so one would not have to fiddle with the XMap? Having to manually adjust boost 'cause of the ambient temp is not a welcome feature, especially in the 4-season climes where weather can, and does, change daily...

 

Shiv your gonna get the new Elise.... dayumn that car is feakin sick. Too bad this ones not powered by the B18C5...

 

Would be better with a 4g63 out of an EVO

 

Why is this happening? What does cold air have to do with how much boost the car is hitting? Wouldn't it hit 19psi in the hot or cold? And what psi does the boost cut at?

 

You don't have to manually adjust boost dependant on weather. It's just that the baseline maps had the boost tables mapped for sea level and 70-100 deg F conditions. With enough free flow upgrades (turbo-back, cam gears, test pipe, etc,.), one can bump up against the factory MAF cut. Keep in mind that this has only happened to a few cars out of hundreds of XEDEs on the road. It is not a chronic problem and is mostly dependant upon car-to-car variance.

My 2c,
shiv

 

So is there a way to "fool" MAF or raise the cut with XEDE and would it be detrimental to the engine? Thanks.

 

BCC from Greddy might work.

Boost Cut Contorler.

But I'm more then sure Shiv has somthing in the works that will be avaliable very soon.

Eric

 

out of curiosity...what happens when the boost is cut....cause last night it was chilly and i would only boost .75 bar all the way to redline....but this morning...things seem normal cause it is much warmer....is that the same thing?

 

Nope. Boost cut feels like someone just turned off your engine for 1/2 a second or so. What you experienced is odd. Like someone disabled your boost control somehow. There are only two ways this can happen: 1) the ground wire came loose or 2) the two wires that you join together came loose. Check both for solid connections.

Also, since the boost cut is MAF triggered, the only way to keep it from occuring is to clamp the MAF signal which would play hell with calculated load. It's not as easy as it is with other cars that some may be familiar with like the WRX which uses MAF for load calculation but MAP for boost cut triggering/boost control. With the MAF trimming that the XEDE does in the fuel tables, the factory boost cut is essentially raised. We just want to raise it a bit more. Not really an issue when running factory injectors and factory turbochargers. But when the big-boys get out, the factory MAF cut is going to get in the way.

my 2c
Shiv

shiv

 

or just get a damn ebc... ALTHOUGH - still see fluctuations in my EBC when it gets cold!

I'll have my SBCID set at 60 for 20psi, but sometimes when cold it will be pushing 20.5 or even 21!

 

Boost pressures with *always* fluctuated with ambient conditions, regardless of what is controlling it. Wheter it's an MBC or an EBC (like the one in the XEDE or a 3rd party boost controller). The key is to dial in the boost so that, under the coldest conditions, boost doesn't go too high and trip the boost cut. This may mean that under other conditions, the boost may be 1/2-1psi lower.

Shiv

 

thanks i will check my connections...but today without touching anything...it was fine....so i dunno