I just got A RENNtech ECU flash and here are the numbers. My baseline Dyno run with K&N filters res-delete were 291.4HP and 301FTQ That was done a few weeks ago. Todays Run with the RENNtech ECU I made 309.9Hp and 319FTQ. I picked up an extra 18.5hp thats even better than what renntech claims. All Dyno runs were done on a Dyno Dynamics Dyno. here are the pics sorry for the size not photoshop at my office

Before RENNtech ECU



After RENNtech ECU

Sweet! Always nice to get more than you expected. Are you gonna hit the strip and see what that does for your quarter mile?

congratz on the extra HP!

Awesome some nice gains!

I think i will soon before it gets to hot here in Phoenix dont think this will put me in the 12's as im a 13.2 now but we will see if a can pull a 12.9 I think thats asking alot though for only 18.5hp gain

Wow! That's damm good!

I would think you could. All my mods dropped nearly (8/10's) off my 1/4 mile and I dont think I gained more than 30-300 hp with them.

I'm not doubting your claims as I have no way to truly refute it. However, if you found 1 second of improvements from a 30-40 hp gain (assuming the higher), then you've tapped into something pretty amazing! It just doesn't add up, assuming all other factors remained the same. It should take more than 30 or 40 hp to drop a 3600 lb car that much in 1/4 ET, unless it's making that additional power throughout the entire power band, and likely would need to make even more power than that down low to get it rolling. The simple laws of physics apply here...
What other conditions changed? Did you drop weight out of the car? Did you have drag radials vs. standard tires? Etc, etc? I'd like to hear the rest of the story to help me make sense of it.

I can tell you I dropped a full second off my ET in my previous car by going from 346cid to 383cid, and picking up an additional 113 rwhp, and 108 rwtq, very proportional across the graph. This was also in a 3400 lb car.

I will agree his gain from the tune is impressive based on others' claims, however he'll be hard pressed to knock 3/10 off his ET with that gain, assuming all other parameters have not changed. Based on what I can see from his graph, it moved the power band up proportionately across the curve, which is a good thing. So, he might see a couple tenths gain from it.
However, the Phoenix heat will play a factor in having higher ET's, at least until the cooler fall weather returns.

Keep us posted. It's good to see real data!

All things being equal, 18 HP equates to a -.18 1/4 mile. Personaly, I would have been disapointed from this gain, for what they charge, IMHO. Hence I have NO tune at this time, but I am leaning HEAVILY towards LET

See yeah

so how does the car feel?
price and did you have to mail in your ecu?

I will have to post the power and TQ sheet as the HP is listed on my Air Fuel sheet the power and attitude of the car changed a bit. It feels better for sure The sound seems deeper at the Exhaust. The sifts are right at red line and feel amazing way better shifts at full throttle though the gears. It only took Dyno-Comp about an our to Flash the ECU files send via email so it was super fast. I got some lunch came back just in time for the dyno run and i was out the door. Kleemann's ecu has to be shipped out and there is a labor charge so that was $1400 out the door not including tax AND YOUR OUT OF A CAR FOR 3 DAYS! Out the door price for the RENNtech was 1700 with dyno runs and i got the car back the in about an hour. Plus they gave me RENNtech Badges for for for for $150 with taxes at 8.9% it worked out well. All I can say is Dyno-Comp in Scottsdale AZ is a killer shop and the Renntech guys there are first class. I was told i may pick up a few more HP as the weekend goes on. I can cherp the tires in second gear now and i wasnt about to do that before. All in all car feels better I'm not going to say way better but better. However it does feel way better though the gears.

ya, me too. Funny thing about my tune, is when we were playing around with it at the strip, we actually lost .5 seconds on the quarter from tune alone.

LET tunes rule....

You'd also have to put into consideration that it's not a force inducted car like the C32 owners. I think he did pretty well if not fantastic. C55asleep? can be more of an insight on these motors than I.

Thank you OP for sharing your experience. I hope next time you'll have a video for us!

I thought i did well too. This is just the beginning for this car.

I did forget to mention I now have drag radials on 16'' enkei's. I was on 19'' inch wheels when I ran the slower time. I was trying to be modest about my gains from my mods and I never dynoed the car so I was just guessing. After I changed the pulley and the heat exchanger I had a completely different car. So maybe I have a few more ponies from my mods than I think. The funny thing is I ran a quicker time when it was 85 degrees out opposed to 55 degrees that same night.

I would like to see some real numbers on a dyno dynamics dyno that can show over 18.5rwhp and 19TQ gain from an ECU flash If you think the kleemann ECU is $1000 think again. Not to mention it took an hour and a half out of my day to do Renntech's ECU ; no overnighting ECU back and fourth. I would like to see other ECU programs that gain more with real data 5 minutes after the flash. If you drove it you would not be disapointed trust me. Right now im all about showing members real gains from added mods it only helps other members spend their mony better than i do

Sorry guys, I thought he was a C32 Which I would have been VERY disapointed with those numbers BTW.

I forgot to read his sig, me bad.

For a NA car, that IS a nice chunck of change, but it still costs WAY too much, IMHO. And the 1/4 drop would still be the same as my original post.

See yeah

i thought he was a c32 as well, dos anyone know any dyno numbers for a c32 with a tune?(since we're on the subject of tunes)

i think its a great gain for a NA car. yeah its expensive, but you get what you pay for. the fact that he was down for 90 minutes is a bonus also. has LET put up any dyno sheets for their 55 na tune? i know theyre big on the the 32, but i dont remember seeing anything on the 55 na. as far as et goes, roughly 10-12 hp is usually good for a tenth or so. good tires, cool air, and the right track could get him in the 12s. that would be nice to see, considering the extent of the mods. thanks for sharing hooleyboy

The numbers seem good as I dynoed 314rwhp with renntech tune and the c/f airbox. Brandon at kleemann took care of me when I purchased my headers. Everything for this car is expensive but believe me its all worth it. Btw DO NOT go the cheap route with these engines at the end of the day it is a Benz's.

Do you have the slips , that makes no sense unless the run at 55 degrees was traction or driver limited. You cannot defeat the atmosphere all cars will make more power at 55 degrees than they do at 85 so you likely erred during your 55 degree run. Other explanation is your car had a mechanical erreor or ecu malfunction during the 55 degree run. I would love to see the slips side by side.

No way you could gain 1 second from 30-40 hp , it would take 3x that however adding the lighter wheels may have freed up 30-40 hp making your gains more like 60-80 which could speed up the car quite a bit.

The faster time slip is at work and its a 13.88. So I guess I better clarify, We'll say 8/10's faster than a whole second. Remember I still have 19's on the front with these runs. As far as it running better when its hot is a mystery to me as well, Maybe its the IK20's I dont know?? The picture with the 3 timeslips is all in the same day. Far left-6.35 pm, Middle 2.06 am, Right 1.00 am. My car numbers are different because I was at the midnight drags for the later runs.

Just wondering what other ECU programs get for numbers. I know stuff I read on RENNtech they only claimed 10ph from there ECU. But just a quick update on the Flash i got. after driving today I did notice and feel a much better pull in the car it also seemed to deepen the exhaust note. I hear the ECU flash can make a few more HP after some driving with it. So now i'm noticing more of a difference in feel

Sweet! I still think you can run a high 12 on a cool night.