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Btw, anybody has a valid before and after dyno run of the Renntech OBD tune? On their webpages they show the before and after but the gain in torque and HP start immediately at lowest RPM (charts start at 2k RPM and lots of gain there already). Most other tunes dyno show gains above 2.5 or 3k to kick in with little to nothing below 2.5k or even 2k. Always wonder if Renntech is just so much better there or just a wrong presentation of dyno curves on their website?
This is the before and after. 6 months apart and the stock run on this only had secondary cats cut out. (dotted lines). other is with catless DP and renntech stage 2.
ill post my exact before and after when i get it done again. problem is my "stock" run will be with catless downpipes too now tho. so not sure how that will affect the stock run.
Btw, anybody has a valid before and after dyno run of the Renntech OBD tune? On their webpages they show the before and after but the gain in torque and HP start immediately at lowest RPM (charts start at 2k RPM and lots of gain there already). Most other tunes dyno show gains above 2.5 or 3k to kick in with little to nothing below 2.5k or even 2k. Always wonder if Renntech is just so much better there or just a wrong presentation of dyno curves on their website?
no dyno but seat of the pants it feels like more grunt down low. That being said, it really comes alive at 3500+. In third gear at 50 mph it will spin the tires up til the 4 shift. Just happened to me on flat, fresh blacktop and 82° out.
no dyno but seat of the pants it feels like more grunt down low. That being said, it really comes alive at 3500+. In third gear at 50 mph it will spin the tires up til the 4 shift. Just happened to me on flat, fresh blacktop and 82° out.
That is what I experience with my tune (Velos), it becomes very noticeable on my butt dyno > 3500 RPM...but would love if I can get those huge gains as in the chart above < 2.5k!! But I dont believe it...at least I am skeptical.
Originally Posted by rbohgan
This is the before and after. 6 months apart and the stock run on this only had secondary cats cut out. (dotted lines). other is with catless DP and renntech stage 2.
ill post my exact before and after when i get it done again. problem is my "stock" run will be with catless downpipes too now tho. so not sure how that will affect the stock run.
Thanks, I have seen that chart from yo before but knowing you have issues up top I was not believing the numbers down low - look around 2.5k hp increases from < 100hp to >250hp? Cant be real, similar on the torque curve goes from 260 to 560 at 2.5k?!
That is what I experience with my tune (Velos), it becomes very noticeable on my butt dyno > 3500 RPM...but would love if I can get those huge gains as in the chart above < 2.5k!! But I dont believe it...at least I am skeptical.
Thanks, I have seen that chart from yo before but knowing you have issues up top I was not believing the numbers down low - look around 2.5k hp increases from < 100hp to >250hp? Cant be real, similar on the torque curve goes from 260 to 560 at 2.5k?!
yeah my dynos something seems far off. the bomb at end of the graph. the way it all drops off. the huge spike in torque. the way it drives its just not powerful enough. we will see how the next steps go in 2 weeks. but im almost at the point of being sick of this car now. which sucks cos i planned to keep this for the next 5 years. widebody conversion, build engine more etc. now i have a bad taste in my mouth from all this. i mean losing to cars in straight pulls that i really shouldnt be... barely walked a stock bmw m2. thats just sad.
yeah my dynos something seems far off. the bomb at end of the graph. the way it all drops off. the huge spike in torque. the way it drives its just not powerful enough. we will see how the next steps go in 2 weeks. but im almost at the point of being sick of this car now. which sucks cos i planned to keep this for the next 5 years. widebody conversion, build engine more etc. now i have a bad taste in my mouth from all this. i mean losing to cars in straight pulls that i really shouldnt be... barely walked a stock bmw m2. thats just sad.
Sorry to hear that. I enjoy mine...now with some extra umph from the Velos tune...even though its not making a difference for my daily driving to work, school, and grocery store but nice to know its there. I had to decide between Velos and Renntech tune and it always intrigued me what huge gains Renntech shows at low RPM but never seen it in a real dyno chart.
I tested MS103 race fuel. Made a blend to bring my car to a true 94 octane (considering my 94 octane up here in Canada is more like 89 octane).
Results:
0-60 no improvement. still sitting from 4.1-4.3 seconds.
1/4 mile no improvement. still above 12 seconds mostly 12.3.
I did notice 4th gear is now a huge power surge. where I'll be honest it's almost too scary? I didn't feel that before.
1st gear- still slips and struggles for traction (running 295's remember on rear and i warmed them up with a burnout first too)
2nd gear- feels like it pulls hard and instant torque
3rd gear- feels a little sluggish dare i say it? now im comparing to 4th gear...
4th gear car pulls hard its liek boost comes in super strong and it flies.
When i raced my friends MT-09 bike he used to jump a car length or 2 ahead from 60kmh rolls. now we were alot closer he was maybe 1 car if that. When we went from a 100kmh roll it was almost dead even now when before he still pulled a car away.
I didn't get anything dyno'd tho. It doesn't seem like the issue is resolved. Yes race fuel helped but it was always going to improve a bit. doesn't seem like its enough.
Anymore advice on what I can get checked? Car was parked over winter... maybe battery? auxiliary battery malfunction comes up still but thats just for stop/start function so i don't think that causes any issues.
sparks are done, air filters new.
I would have a CEL if i had a boost leak, thought maybe downpipes were damaged somehow. Need advice please this car is frustrating me now! meant to go to Area 27 racetrack on june 14 but with it performing like this I don't even want to go
You my friend, are describing perfectly what the stock TCU does when not modified. Look into TCU tuning as there is a ton of great info coming to light.
You my friend, are describing perfectly what the stock TCU does when not modified. Look into TCU tuning as there is a ton of great info coming to light.
Yes but that still doesn't explain the 60-130 times being so far off other tuned cars that also don't have a TCU tune. Currently having a similar issue to a lesser extent with my eurocharged tune. 60-130 @9.5 when it seems like properly tuned cars should be in the mid 8's.
For me I know its not the gas as im putting shell 93 in it and have tried a variety of gas stations with no change in performance.
You my friend, are describing perfectly what the stock TCU does when not modified. Look into TCU tuning as there is a ton of great info coming to light.
Hey sorry for late reply here. and TCU tuning? Im going to research that now haven't come across it before. thank you!!
Yes but that still doesn't explain the 60-130 times being so far off other tuned cars that also don't have a TCU tune. Currently having a similar issue to a lesser extent with my eurocharged tune. 60-130 @9.5 when it seems like properly tuned cars should be in the mid 8's.
For me I know its not the gas as im putting shell 93 in it and have tried a variety of gas stations with no change in performance.
OP what year is your car?
Did you get a TCU tune? my car is a 2015. ill post a full update of my cars progress below
Apologies for being so late with an update here. This year has flown by. got married recently!
So my car... Renntech did a great job retuning and sending me back the HHT. I still use a 10% ethanol blend with the 94 chevron (remember our 94 in canada is more like 89-90 octane). I use one full can of Torco Accelerator in each tank too. Amazing job this does. On the dyno while the ECU was still pulling timing i got an extra 30hp and 50tq by just adding in one can.
I haven't had time to get the car dyno'd again. But my 60-130 has gone to 9.36 from 10.6-11 I was getting before. I'm sure I can get closer to 9 seconds too. I beat a Huracan twice on the highway from 100-220kmh. Biggest scalp i've taken and haven't lost yet. Tied dead even with an 800hp charger hellcat and a stage 2 cls63.
So im impressed with the power delivery especially in 1st-2nd so much torque so early the car is ridiculously fun and 4th and 5th gear feel like rocket ships now (long as I keep the Torco use up... without Torco I go straight to limp mode even if I still run ethanol blend. Im trying to get a sponsorship deal going haha) also the Renntech BOV sounds amazing. still loving that.
I need to look into TCU tuning. That is new to me still.
My goal was to get up past 800hp with Renntech. but right now they are charging almost $50k CAD to make that happen. Won't do an e85 tunes or WMI. Just want me to use race fuel which is hard to get here and also super expensive. I hear eurocharge does full e85 tunes. So i have all winter to research and figure out what I want to do. The plan was a widebody stage 4 renntech 900HP showcar. Who knows what I'll end up doing now. Step by step....time for TCU....
EDIT: far as im aware Renntech already does the TCU on their ECU tunes. waiting for confirmation from them.
I haven't had time to get the car dyno'd again. But my 60-130 has gone to 9.36 from 10.6-11 I was getting before. I'm sure I can get closer to 9 seconds too. I beat a Huracan twice on the highway from 100-220kmh. Biggest scalp i've taken and haven't lost yet. Tied dead even with an 800hp charger hellcat and a stage 2 cls63.
Nice improvement. So in summary, did RT say it fuel alone was the reason your original times and dyno were low?
Originally Posted by rbohgan
I need to look into TCU tuning. That is new to me still.
EDIT: far as im aware Renntech already does the TCU on their ECU tunes. waiting for confirmation from them.
Can someone explain TCU Tuning? I happen to have a Stage 2 EC Tune I got in Added late 2019 on my 2017 C63 AMG Sedan thats stock except AWE Exhaust.
EC Just Announced they unlocked 2020 MB ECU AND they said we are NOW Offering TCU Tuning starting at $1,495.
Is TCU just adjusting how the transmission behaves and the shift points and how much pressure the car shifts? Again I heard people talking about they wish they could modify TCU, but don’t know What YOU GAIN From doing this.
I am still going to Dyno my car to KNOW how it’s running and to make sure Air Fuel is correct and it’s no Rich or Lean. It would give me peace of mind KNOWING what my car is doing and what gains I’m getting from Stock vs my Stage 2
I would search for a lot better info, or contact one of the vendors that is doing TCU tuning now, but in one sentence: The factory transmission computer programming will limit torque of the engine to protect the trans, and TCU tuning raises the tq limits and (i presume) line pressure so the trans can actually handle the increased tq.
Without TCU tuning the transmission will actually limit engine power despite your ECU tune.
Nice improvement. So in summary, did RT say it fuel alone was the reason your original times and dyno were low?
Highly doubt that.
waiting on renntech to confirm TCU still.
and they didn't really say what was wrong with the mapping the first time. said they changed a bunch of things based on the logs i sent them. and it fixed it all. now its running strong
This has been a very intriguing thread for me, as the second owner of a 19 c63s sedan.
I've spoken with RT, and they have confirmed that the can already provide HHT for the 2020 (and 19's with latest ecu firmware/update). So that it excellent news.
Further, I inquired about TCU and (for us 19 and newer guys) cpc module tuning.
RT told me that they expect to have full transmission tuning by the end of the year, and that they will be able to flash the TCU and CPC module all at the same time without having to physically remove the cpc.
Overall excellent news for everyone here.
fwiw, and as it more specifically pertains to this threads topic, I already have hptuners on my laptop, as I'm coming from a tuned, bolted on, and meth injected ATS-V. I have gathered here that people can log these cars with HP tuners, but cannot write the ECU I hope to learn more about that soon as I would like to log my car even at stock levels to make sure everything is healthy prior to any modifications.
I hope to learn and contribute here as much as possible. Thanks for a great discussion.
This has been a very intriguing thread for me, as the second owner of a 19 c63s sedan.
I've spoken with RT, and they have confirmed that the can already provide HHT for the 2020 (and 19's with latest ecu firmware/update). So that it excellent news.
Further, I inquired about TCU and (for us 19 and newer guys) cpc module tuning.
RT told me that they expect to have full transmission tuning by the end of the year, and that they will be able to flash the TCU and CPC module all at the same time without having to physically remove the cpc.
Overall excellent news for everyone here.
fwiw, and as it more specifically pertains to this threads topic, I already have hptuners on my laptop, as I'm coming from a tuned, bolted on, and meth injected ATS-V. I have gathered here that people can log these cars with HP tuners, but cannot write the ECU I hope to learn more about that soon as I would like to log my car even at stock levels to make sure everything is healthy prior to any modifications.
I hope to learn and contribute here as much as possible. Thanks for a great discussion.
Renntech replied to me:
"We’ve tested the TCU on the C63, but the results were not that good. The TCU upgrade changes the Torque limits in the lower gears. As you probably know, the C class already fighting with traction issues. So raising the Torque limit would not really help"
I am now talking with Eurocharge about a larger build...Slav said:
"If you want 800whp you will need the pure 1000 turbos, meth from Weistec, heat exchanger, xdi or spool di pumps, tcu tune.
The car will also need to be dyno tuned. Call me and we can discuss what to do"
05-30-2020, 02:32 PM
