• BenzBoost member reviews his Renntech HHT (OBD-II Hand Held Tuner) W212 E63 AMG M157 tune - Full Review w/ Datalogs

      The review below is from BenzBoost Mercedes-AMG Automotive Performance Forums member 5soko who purchased Renntech's HHT. The HHT is a handheld tuning device which allows you to flash your car at home in the comfort of your garage through the OBD-II port.

      Hey guys!

      This is gonna be a long review so strap in. So after putting off getting a tune for a while now, i finally felt comfortable enough with the information and knowledge i learned, that i would give it a shot. Im not here to knock on anyone or any company, or give false praises where they arent due. Im a forum enthusiast, love my car, work hard for my money and from the friends i have made on this forum who know me, im straight with my answers and thoughts. Im here to share my experiences good or bad so it can help the next guy in our community make a final decision, this is the beauty of a forum and why we are all here, to help each other.

      Choosing a tune:

      Researching, emailing, talking to different companies and talking to forum members here via dm and in person, all have led me to my decision.

      Renntech has always been the classic household name for AMG tuning. All our members here i spoke to all seemed to be happy with their tune. It made great power, no common misfire issues, and their cars were fast and reliable. Renntech it was!

      Getting the tune and some background:

      After 10 months with the tune driving in cold months and warm months (back into the cold now again), i feel like i can give my honest opinion and share some datalogs with you guys, which from what i know is a first on the forum.

      First things first, contacting via phone and email to Renntech was easy and they answered all my questions. I had a whole list of questions which they answered on different occasions via phone call and email. Patrick at Renntech was great to deal with, had him on call via phone and email at any time i needed him. Their engineer Austin was great to deal with as well, for all the more in depth technical questions i had.

      This goes along with the great reputation i have heard of them. It was nice to see it personally for myself. I never had any Renntech products before, so i was excited to see how the whole experience goes.

      So, i went ahead and ordered the Renntech ECU+ tune for 93 octane.

      Renntech offers, 91 octane ECU tunes, 93 octane ECU+ tunes, and an 93 octane tune with their blow off valve or Diverter valve as they call it or R1 Package, which runs about .5 to 1 psi more than their 93 octane ECU+ tune. They also optimize the intercooler cooling system as well.

      I got their 93 octane ECU+ tune . This tune runs 18.5-19 PSI.
      For reference 2014-2016 M157's E63 S models run a peak of 14.5 PSI stock.

      Renntech now uses a very neat and convenient handheld tuner or 'HHT' to flash the ECU via the OBD.

      This HHT doesn't require any cables, or laptops or cell phones. Just flip the switch on the handheld to either stock tune or your performance tune, and plug into the OBD under the dash. Really cool, simple to use and stores away in the glovebox or anywhere since its so small. Very neat little tool!

      HHT came beautifully packaged with instructions and a few nice renntech goodies, like pens, poster cards, and such.

      Renntech advises to change plugs 50% sooner then oem intervals when tuned, so every 30K miles. OEM plugs only. And stock gap on current plugs if they arent old, and you dont have issues. Next change of fresh plugs they advise to gap smaller to 0.22 from 0.28/0.29 the oem plugs are at for preventative maintenance. So i have been running oem plugs, at oem gaps and it has been working perfect!


      Plugged in the HTT, flashed the ECU for Renntechs performance tune, and started her up! Nice and smooth, no cel or codes etc, ready to go.

      Went for a easy ride to warm everything up and started slowly leaning on the throttle more and more to adapt the car, right away i felt the linear boost in the throttle and felt it pulling very strong down low.

      Stopped in at the park, went for ice cream and some scenery views. Jumping onto the highway on ramp, i went for it, WOT, and car was absolutely freakin flying! Felt beastly! Tq was amazing, so effortless, midrange was BRUTAL, and the top end was very strong! This tune really OPENED the M157 up, and the car just kept sinking my stomach in everytime! It really gives you that tunnel vision you see in movies because everything moves so fast. Car was violently good! I was really impressed to get so much power that i could actually feel! Few more pulls, both hands holding onto the wheel and i was genuinely impressed with the power!

      The consistency in the power of the car was also very important. Car was able to perform back to back runs with the same strong impressive pull power. The pulls throughout the day felt all strong and the same, as where some tunes feel a bit off at different times i experienced in the M157. This inconsistency with other tunes i felt may be due to bad boost control and timing being pulled aggressively. But the Renntech tune felt on point each time!

      Throttle response is nice and linear just like stock, no complaints there as many companies are a bit aggressive in their throttle mapping, you get a rush of boost with little throttle input that you didn't request with your right foot.

      Big factor for me is the tune runs and works great in normal day to day life aswell. Nothing has been compromised here for more power which is exactly what i look for in a tune. Just feels exactly like factory until you start digging your right foot in.
      Afterall we are all here for a some more power but not to sacrifice how our cars drive when we arent at full throttle.

      Put it in C, drives nice and smooth like its a ordinary AMG. Went to dinner later that evening and came home, gave my car and Renntech a thumbs up in my garage, was very happy with my decision.. Not only did this tune make the car a much more fun to drive , but it also made driving normal easier, so much tq to go around eveything like a sling shot with ease and low revs.

      The way the car just blasts down a road really transforms it into another league of car altogether. A Four door sedans shouldn't go this fast!

      Honestly, all the research, emails, PM's was worth it.. Renntech is definetly not a hype, and i knew this after talking and driving a few other tuned E63's. Now having it on my car, I am beyond happy and my worries are out the window. I wish i would have done this sooner, but i hope this helps alot of guys if they are in my shoes before i ordered.
      Its pretty much like having a factory tune on the car, that is how seamless it all works. No issues in all 8 months, no CEL, no misfires, not even a hiccup. I still till this day just am so impressed with the TQ and the HP every time i put my foot down!

      Renntech was a pleasure to work with and my overall experience was very positive.
      Renntech lived up to their reputation i have heard for so many years.
      Talking to and answer all my questions! I know i was a big pain in the ***!

      Big shout out to Patrick at REnntech, he was a great help, treated me right the whole experience, Via Email and telephone.

      I honestly enjoy sharing my stories when a company from start to finish makes a customer happy and in my case this thanks is well deserved for them. I work hard for my money, love my car, and love the passion for cars and modding. Its always so nice to see a company treat people right, and do right with their products! Thanks to all the forum members who have helped me along the way aswell in answering my questions and meeting up with me.

      My Renntech tune consisted of:
      -93 octane tune
      -Top speed limiter delete
      -ECO mode de-activated


      There are plenty of 1/4 runs and dynojet graphs on here from the past few years, but there isnt any actually datalogs review from the entire era of this M157 forum.

      All due respect to Renntech, im sure they make great tunes and its safe, BUT i wasnt gonna write this review until i saw for myself, personally, how my car datalogged and what the #’s showed to share with everyone. Teaser: Turned out excellent

      In my N54 335 days, i was heavily involved in tuning and was one of the first ever guys to run a jb4 when terry and burger tuning first ever started and opened their doors.. I did alot of beta/alpha testing and logging for years for Terry.. Was alot of fun..
      I also paved the way for the E60 M5 fine tuning and datalogging. I helped also refine and test Eventuri's first ever intakes as well.

      So here is some actually data via HP tuners datalogging software. For another future thread, i will be comparing and showing some others tuners datalogs for transparency to everyone to compare. I know a few forum members who is running X and X tunes who datalog, they were told not to share logs with me or to the public community, so that's a real bummer.

      Our cars are tuned via boost by load.. So, To hit the same load target in cold weather requires less boost/air of course, and to hit similar load target in hot weather will require more boost/air.

      Stock tune, peak boost in 40F, about 12 PSI @ 5,200 RPM tapering to about 8-9psi to redline.

      Full throttle, our high pressure fuel pump are injecting fuel at an impressive 2900psi, so its cool to see our fuel system working strong!

      Timing is good with no real drop outs, which is expected on a stock car on 93 octane.
      AFR is clean and rich.

      Renntech tune, peak boost in 54F, about 17-18PSI @ 5,200 RPM tampering to about 12-13 to redline. Boost control is smooth and clean just like stock and you can feel that on the road.

      Fuel pressure is again strong, AFR richer then stock, timing is clean with no dropouts aswell. Solid report here from Renntech, hats off to the guys!

      Some pics:

      Not all are created equal:

      Here is also some interesting stuff you guys might like, which i found surprising during my testing

      Here is a datalog of 3 cars.. My stock car, My Renntech tuned car, and a Tuned third party car which is popular among the M157 world, All showing throttle body position. All 3rd full gear datalogs. All E63 S AMG 4matics on 93 octane.

      Stock, Yellow line is the actual throttle plate position here, and pink line the actual gas pedal.

      As you can see the throttle plate stays open the whole gear during full throttle. excellent.

      Here is my Renntech tune.. Gas pedal being the top line and the yellow line being throttle plate, you can see 2 small corrects in the throttle plate where the line dips slightly, a few %, very minor, overall clean.

      Here is a friends and forum members car, tuned car that i wont name.
      You can see here the top line, gas pedal is full throttle during the run, but the yellow line, the throttle plate, has two massive closures.

      Thought this would be interesting to showcase, bring light to, and compare. As these throttle closures of course happen for many reasons, usually minor closures is perfectly normal to control boost, load, etc. But you dont like to see these big throttle closures, as you cant feel them usually in your butt dyno, this will make the car feel inconsistent in its power, less aggressive, and of course reduce power.

      This is why i urge everyone to grab a datalogger if you are curious to see how your car is running and share. Esp the modded crowd here.

      I've seen all kinds of fun things from the aftermarket tunes out there via datalogging, huge advance timing, big boost tapers, throttle closures, etc.

      Thanks for reading guys!

      This article was originally published in forum thread: 5soko || Renntech Tune HHT.. Full Review w/ Datalogs started by 5soko View original post
      Comments 3 Comments
      1. Sticky2's Avatar
        Sticky2 -
        Dude what a review!!! This is going on the front page.
      1. dasbigunit's Avatar
        dasbigunit -
        I joined this forum just to give this review a Click here to enlarge. It helped me decide to pull the trigger on my HHT.
      1. 5soko's Avatar
        5soko -
        Click here to enlarge Originally Posted by dasbigunit Click here to enlarge
        I joined this forum just to give this review a Click here to enlarge. It helped me decide to pull the trigger on my HHT.
        Thanks u very much, appreciate it! Enjoy!