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Had the RennTech TCU software loaded yesterday @Axel's Automotive, Lake Bluff IL. Nick Knauz was very helpful, scheduled the upgrade and had the equipment shipped from Florida the day before. Took about 1/2 hour. The change is noticeable. Initial impressions are, improved response and much more tire spin . Yesterday was warm ( 85 ) and Race Launch was useless, spun and short shifted 1-2-3. Below are reports from a V-box like device, Dragy. 3.48 0-60 was done just before the TCU update and 3.28 0-60 done just after. Mash and go in Sport+ and traction in sport.
Thank you for being a lead adopter and taking the time to document the before and after! The initial part of the acceleration curve is noticeably higher G's that the stock readings. This shows the impact of the TCU upgrade. On the 0-60 times i see a bit of down hill on the stock run and going up hill slightly on the tuned run. So flat to flat compare the 0-60 time should be a bit more improved for the tune.
Wow, great feedback! Do you also have their ECU tune?
I have AMS ecu tune, I purchased before the TCU became available.
Originally Posted by TRIAgain
Thank you for being a lead adopter and taking the time to document the before and after! The initial part of the acceleration curve is noticeably higher G's that the stock readings. This shows the impact of the TCU upgrade. On the 0-60 times i see a bit of down hill on the stock run and going up hill slightly on the tuned run. So flat to flat compare the 0-60 time should be a bit more improved for the tune.
Good work RennTech.
I agree it seems to have more punch in the first bit. I will try and update, for now it seems to be a pretty solid change.
I have AMS ecu tune, I purchased before the TCU became available.
I agree it seems to have more punch in the first bit. I will try and update, for now it seems to be a pretty solid change.
Great stuff! I have an AMS Alpha tune underway. Used ECU on order. I expect to have the tune in about 10 days or so. My question here is with an ECU tune. Using a used ECU with your virgin ECU in your pocket you can still keep your warranty intact unless someone is stupid. lol. Have you got any workaround or worries about a TCU tune being detected by the dealer? What if they update the TCU at one of your services and overwrite your new tune? Basically, logistic questions.
On a separate note, I have had my new VBOX for a few days now and I cannot seem to beat 3.8 secs 0-60. I average about 3.9 to 4.0. Tried RS launch, traction off in M mode, traction off in S+, Full brake stand. It looks like I am losing most of my time right at the start, 0-10. Taking me 0.8secs 0-10 almost every time. My 2011 is faster 0-10. ALso, with traction fully off on the 2015 I can't seem to break any tires loose at all. I realize its still possible and just not heard. But I don't sense it happening at all. That darn lag is awful on this M157. Thinking about Sprintbooster. Not sure if that will help the 0-10 though.
When you got your AMS tune, did it noticeably improve the lag issue by any chance?
Happy you posted this so I know exactly who to to ask these questions too!
Lastly, Can you share exactly what you have found as the best process in these cars 0-60?
Great stuff! I have an AMS Alpha tune underway. Used ECU on order. I expect to have the tune in about 10 days or so. My question here is with an ECU tune. Using a used ECU with your virgin ECU in your pocket you can still keep your warranty intact unless someone is stupid. lol. Have you got any workaround or worries about a TCU tune being detected by the dealer? What if they update the TCU at one of your services and overwrite your new tune? Basically, logistic questions.
Dealer has been mod friendly, not too worried. Always is a chance it voids warranty of course. I don't think they update the TCU often, I took it in a week earlier for sluggish transmission I was told it's normal haha.
Originally Posted by Vrodman
On a separate note, I have had my new VBOX for a few days now and I cannot seem to beat 3.8 secs 0-60. I average about 3.9 to 4.0. Tried RS launch, traction off in M mode, traction off in S+, Full brake stand. It looks like I am losing most of my time right at the start, 0-10. Taking me 0.8secs 0-10 almost every time. My 2011 is faster 0-10. ALso, with traction fully off on the 2015 I can't seem to break any tires loose at all. I realize its still possible and just not heard. But I don't sense it happening at all. That darn lag is awful on this M157. Thinking about Sprintbooster. Not sure if that will help the 0-10 though.
When you got your AMS tune, did it noticeably improve the lag issue by any chance?
I would say the lag was more obvious after the tune. When stock the power delivery is pretty linear, not as much so with a tune.
Originally Posted by Vrodman
Happy you posted this so I know exactly who to to ask these questions too!
Lastly, Can you share exactly what you have found as the best process in these cars 0-60?
It really depends on the surface for my car, sometimes the Race Launch really hooked. I can brake stand it back to back and not hit limp mode but it seems to break loose really easy. I would say; traction off and brake stand to 3100 rpm would be ideal if on a prepped surface. Mostly it's a mash and go method.
Dealer has been mod friendly, not too worried. Always is a chance it voids warranty of course. I don't think they update the TCU often, I took it in a week earlier for sluggish transmission I was told it's normal haha.
I would say the lag was more obvious after the tune. When stock the power delivery is pretty linear, not as much so with a tune.
It really depends on the surface for my car, sometimes the Race Launch really hooked. I can brake stand it back to back and not hit limp mode but it seems to break loose really easy. I would say; traction off and brake stand to 3100 rpm would be ideal if on a prepped surface. Mostly it's a mash and go method.
Savage - appreciate the feedback as I've been thinking about that AMS tune since I'm also in Chicago and had not thought about the TCU tune but will after your review.
Curious, what MB Dealer in Illinois do you go to? i live downtown and been taking my care to Fletcher Jones MB Chicago and not been very happy with their warranty work....
Savage - appreciate the feedback as I've been thinking about that AMS tune since I'm also in Chicago and had not thought about the TCU tune but will after your review.
Curious, what MB Dealer in Illinois do you go to? i live downtown and been taking my care to Fletcher Jones MB Chicago and not been very happy with their warranty work....
Any authorized Renntech installer can do this now?
I think only some can. I contacted renntech and they put me on to a installer. It was my understanding that they ship compter hardware too the installer and coordinate with the Florida office to remote into the system.
Savage - appreciate the feedback as I've been thinking about that AMS tune since I'm also in Chicago and had not thought about the TCU tune but will after your review.
Curious, what MB Dealer in Illinois do you go to? i live downtown and been taking my care to Fletcher Jones MB Chicago and not been very happy with their warranty work....
Car magazines use 1 ft rollout for their 0-60 ... keep in mind
all our 0-60 numbers would be better if we accounted for That
My VBOX says it does in fact use a 1-foot roll out. Today at lunch I managed a new best at 3.7. Still can't get to the reported 3.5. It really seems to be the 0-10 that is killing me.
Do you know where in FL the home base is?
Does this TCU tune allow the car to brake boost a higher rpm from a dig? Right now when I launch with traction off/Sport + mode, the highest I can get the RPM’s to is somewhere between 2,500-3,000, and that’s with my left foot hard on the brake and my right foot flooring the gas pedal. The stock tcu is totally killing the ability to launch this thing properly; the best 60 ft I can get is a 1.85 and there’s NO wheel spin. I’m trapping 123mph but can only pull 11.6-11.7’s. I’m sure it would be in the low 11’s if I could launch better
My VBOX says it does in fact use a 1-foot roll out. Today at lunch I managed a new best at 3.7. Still can't get to the reported 3.5. It really seems to be the 0-10 that is killing me.
Whats your 1/4 mile? I think that’s a better measuring stick to use
Do you know where in FL the home base is?
Does this TCU tune allow the car to brake boost a higher rpm from a dig? Right now when I launch with traction off/Sport + mode, the highest I can get the RPM’s to is somewhere between 2,500-3,000, and that’s with my left foot hard on the brake and my right foot flooring the gas pedal. The stock tcu is totally killing the ability to launch this thing properly; the best 60 ft I can get is a 1.85 and there’s NO wheel spin. I’m trapping 123mph but can only pull 11.6-11.7’s. I’m sure it would be in the low 11’s if I could launch better
RENNtech, Inc.
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I can brake stand up to ~3500 . With the traction in sport it freaked out and didn't go. With off it spin and shifted short..
Glad to hear someone's evaluation of the TCU tune. Was the cost what is published on the web site or is their other charges? It would be nice to see 1/4 mile times for comparison.
Thanks for the informative post after reading this I actually contacted Axel's automotive as they're 15 min away from me and will probably end up doing the tcu tune after I get my downpipes and ecu tune installed. Only thing is I wish you could do race start with traction control off.
05-03-2018, 09:14 AM
. Yesterday was warm ( 85 ) and Race Launch was useless, spun and short shifted 1-2-3. Below are reports from a V-box like device, Dragy. 3.48 0-60 was done just before the TCU update and 3.28 0-60 done just after. Mash and go in Sport+ and traction in sport.
