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Well I woukd say the first thing to get straight is to know what the 900r is suppose to make for boost (~17.5) and is it achieving its target boost.
Its unfortunate there is no way to datalog (pv3) I do have a prologger so that is coming back out and onto the mach next week to join tree guy to verify motor is making max power as it should before clutching changes...
 

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According to that dyno sheet if you are at 7500-7700 that is were you want to be.
Myself i would want to be 7900-8000 to take advantage of all the extra rpm you can get without loosing too much hp/tq from peak.
At 7950 you are 3hp down and 6 ft/lbs from peak so the extra rpm outweights the little loss of power IMO
 
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When i pick up my mach this week i am installing this boost guage and will have my eyes glued to it since there is no way to datalog any useful info.
Im not touching any clutching until i am convinced this engine is boosting and running 100% Gadget Measuring instrument Rectangle Sports equipment Tool
 

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Yes, worthwhile to see if octane boost makes a change. My guess is that octane is not likely to enter into this matter: Adding octane does not add power, only detonation resistance. Having said that, a given higher octane fuel may run better with more power, but that is usually due to a different additive mix, like less ethanol, not the octane rating. The ECU has no way to measure octane... it only reflects in detonation.

One major design goal here in a production sled is to avoid detonation. This is not a diesel with the heavy internal construction... detonation is any everyday thing in diesel-land. You can be sure they kept a lot of margin in the programming to detonation. Can anyone cite that source of the 17.4 psi max boost? I'd like to see the context; that may have been early promotion and the reality crept in later to force a lower limit.

And yes engine temps enter into the programming action. IDK what they may be doing with engine temps here other than the obvious warm-up enrichment, and controls for overtemp situations. The main temp used is the IAT (inlet air temp) which is used to approximate air density.
See post 230 for where the 17.4 came from
 

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Is it the Koso X-1 ?

Let me know where you put the boost sensor on the 900R. If you can take a picture, it would be appreciated.

Envoyé de mon SM-G960W en utilisant Tapatalk
Yes it is and can do..
 

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I dealt with turbos and tuning a lot in the automotive end of things, and one of the biggest problems with boost I found was a turbochargers ability to maintain boost levels as rpm and airflow volume increases. Low end transient response and high rpm flow rates are a delicate balance. I’m wondering if the turbine is just unable of maintaining 17+ psi of boost at high rpm on these motors
If this theory was true then why does the 900r that hurricane and Whalen run aftermarket ecus in work just fine at 20psi+?
I think engine mechanical hardware is just fine..
 
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This ecu will not be flashable.
EVO powersports and many others spent over a year since this ecu came out in the sxs to try and flash and have not been successful.
Best they can do is that you can send your sxs ecu in, they disassemble it, modify it by physically removing or modify the area that is in charge of the encryption, so then it cAn be flashed.
They said it is impossible to break the encryption otherwise. Go to evo to read more..
 
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I have a 1060 miles on my Machz it runs 7700 RPM it has a 1.5 ripsaw track on it with no studs we drive stumble fields and trails here on the prairies.I am running the XS 821 belt.150/300 spring in the primary.The rear driven is stock have done some testing with a data logger
I have put in Dalton 850 clicker ramps it’s makes it very responsive now almost like a 2 stroke.
So all my testing is field testing so no running on ice or anything like that and this Machz is very fast and getting faster I don’t know what it would run like on a good surface very happy with it here are my times.iCloud
So what rpm are the 850 clicker ramps running? You want to be at 7900-8000
 

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Ha ha ha !!!!! I ran a tuned 900R this weekend and it was strong in the middle but nothing up top past 90……The Mach Z owner, who owned the tuned 900R said the Mach is a big heavy pile of junk and he said I won’t even line up with you. He also state his 205 tuned 900R crushes his Mach.

Now to put this into perspective, this guy owns every Mach Z ever made and has them all yet in his garage. He said Doo sold us a bill of goods on this sled, it’s slow and handles for ****. He went on to say he has thrown everything it clutching wise and can’t make it go faster than an 850 and it loses to most 850’s .
There is no such thing as a tuned 900r. Unless it has a aftermarket ecu
Did you mean 900T?
The 900r ecu is currently locked and not tunable
 

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Not really a fair comparison. So what happens when some puts a motec on the 998? But, I get what you are saying... These sleds are big couches are snow!!
Actually the 998 ecu does a really good job when tuned of maxxing out the engine on pump fuel and even with race gas.
Adding a motec to a 998 wont really do much overall, it will give you better datalogs and more flexibility to make more power eg.- aux injectors- so his comparison of the motec 900t to a 998 with a tuned ecu is apples to apples in his case
 

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7900-8000 is what everyone seems to shoot for with the 900’s. I think ever. If you are running 8000 the 880 ramps pull much harder and I think there is still going to be some overshift.
What were you getting for top speed before and now what are you seeing?
 

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Read up on 2048 rsa key and you will see that it wont be hacked.

"2048 bit RSA key is something called asymmetric cryptography. It is used for validating identity (signing) and ensuring that only an intended recipient can access the information sent (encryption). It is composed of two pieces, a public key and a private key."

It hurt my brain to read it all..lol it is why evo had no choice but to physically remove the part of the ecu that contains this encryption instead of the usual electonic hack n flash.
 

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Yup normal. Ypu are getting really good shift out actually. No problem there...
 
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