Let us know if the crank relearn solves your issue devilish64.
Down on power
- Thread starter devilish64
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I will.... just got my x4 today.... have to run the e85 out of my tank and put some pump gas in it and put on my k&n intake in hopes of the car running well enough on the stock tune to make the crank relearn work
Good luck, I'm sticking with this thread til the end.
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Took my car to the track this weekend and im back to the same crap that your going through. I have the rxt as well,I did the crank relearn with the x4, even put a lund tune and 2.5 upper on . Im down 7 mph in the quarter and more than half a second slower than my best run stock!!. I may try back tracking and start putting stock components back on the car till i see some improvement. this is really starting to piss me off. I love the styling and heritage of this car but holy shit what a mechanical nightmare!!! And this aint my first rodeo.
This is where I'm at as well.... I've never had such a problem diagnosing an issue with this car... I am the one most of my friends with Shelby's ask questions when they have issues, so not being able to solve this is pissing me off as well
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I am trying to learn about data logging now so I can see if timing is being pulled or if throttle is shutting down then maybe I can pinpoint the problem. I am starting to believe the rxt is transmitting too many noises that are sounding like knock and retarding the timing big time. will report if I have any findings though i don't have much time left as the cold is coming around where I am an it will be storage time for my grumpy Shelby.
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Took my car to the track again. I noticed in the last track visit my car would drop off power as i shifted. I thought maybe im hitting the rev limiter and its pulling a bunch of timing. I raised the rev limiter to 6550 (still shifting at 6k) also datalogged my knock retard. it turns out my knock retard is is at 129 briefly after each shift. There is still some investigation to be done here but I think we are onto something to do with the RXT and noise acting as false knock.as a side note I did raise my idle to 1000 rpm and there is less transmission noise when stopped and at idle.
So I plugged in the updated x4 tuner and tried to find the crank relearn under the special functions on the device and all I could find was the KAM reset. Has anyone done the crank relearn on an 07 GT500 and can confirm it is possible on an early model?? I am on the stock tune so I don't think that's an issue
I'm not sure to be honest! I will check that at some point.
So today when I tried to do the crank relearn I filled the tank with 5gallons of CA premium pump gas (91) so I could try and use the stock tune. After unsuccessfully trying to do the crank relearn I decided to load my VMP pump gas tune.... my car is pullied for ~21 psi of boost so I knew the 91 wasn't nearly adequate so I filled the rest of the tank up with with 100 octane race gas and sure as shut the car felt like it gained a ton of power. I don't think I ever loaded this tune as I have been running e85 for close to a year now. I wouldn't say that the pump gas tune is as strong as my e85 tune use to be but it is surely better than my e85 tune feels now.... the car seems to have Better drivability and doesn't have the same lag when quickly letting out the clutch or quickly a stabbing the throttle. It spins my 315 nittos in second easily now. I don't know how my tune wich had been previously running excellent could feel so bad so suddenly but for some reason after I installed my RXT the car never ran right on my e85 tune. I don't know why that would happen.... it probably doesn't make any sense that it could but it certainly feels better and I'm glad.... I'm tired of being the one with the slow, fast gt500 in my group
So today when I tried to do the crank relearn I filled the tank with 5gallons of CA premium pump gas (91) so I could try and use the stock tune. After unsuccessfully trying to do the crank relearn I decided to load my VMP pump gas tune.... my car is pullied for ~21 psi of boost so I knew the 91 wasn't nearly adequate so I filled the rest of the tank up with with 100 octane race gas and sure as shut the car felt like it gained a ton of power. I don't think I ever loaded this tune as I have been running e85 for close to a year now. I wouldn't say that the pump gas tune is as strong as my e85 tune use to be but it is surely better than my e85 tune feels now.... the car seems to have Better drivability and doesn't have the same lag when quickly letting out the clutch or quickly a stabbing the throttle. It spins my 315 nittos in second easily now. I don't know how my tune wich had been previously running excellent could feel so bad so suddenly but for some reason after I installed my RXT the car never ran right on my e85 tune. I don't know why that would happen.... it probably doesn't make any sense that it could but it certainly feels better and I'm glad.... I'm tired of being the one with the slow, fast gt500 in my group
You should probably buy an e85 tester. You might have some shit quality in your area at the moment.
Take a look at water/meth injection maybe as an alternative to e85. Thats the direction im going for damn sure, confidant Lund will have a great update for my tune when i do too.
Take a look at water/meth injection maybe as an alternative to e85. Thats the direction im going for damn sure, confidant Lund will have a great update for my tune when i do too.
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Datalog and send it to us if you're running our tune. Unfortunately we can't see who you are on forums.
vmpperformance.com
>>customer support (where to load datalogs)
>>>vmp garage (how to datalog)
bj
vmpperformance.com
>>customer support (where to load datalogs)
>>>vmp garage (how to datalog)
bj
Michaelh_133
New Member
Hey did you ever find out the exact cause to this issue? I've read the whole thread and I'm having the same exact issue at the moment.
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