Stimpgsx

Took my c400 to the track last friday. The car ran solid with a constant 12.8-12.7 at 108-109 mph. Ran the car 4 times. Ran pretty strong for a heavy sedan. Ordered downpipes and exhaust which i think will help top end. Car only has k and n filters and K box. Anyone with a c450 in Atlanta want to run it? ��


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First run

angeloxnet

kleemann?

InTheBenz0

yes, it makes the least amount of the piggybacks as it taps into fewer things when attaching it under the hood.

Stimpgsx

Yeah, its a Kleemann K box. Im going to see how it runs with this and downpipes and exhaust. I want upgrade turbos and IC and fuel but no one is willing to touch it. Most of the big shops are mostly focused on the c63.

angeloxnet

have you put it on a dyno for a baseline? im curious if the car is underated and/or if you are seeing the advertised gains of the k-box

Stimpgsx

Havent dynoed it but i can tell you that the car ran a 13.4 at 106 completely stock a year ago. Ran it 4 or 5 times and couldnt do any better. The kbox did make a difference and the car ran a best of 12.7. That puts it in stock c450-c43 times. I have not used race gas as kleemann states 400+ hp with race gas but i dont know about that. I think the additional boost gives it a good 35-40 hp if anything

Pete400

I have the same setup as you, and i just adjusted my kbox settings yesterday. Immediate noticeable results... If you open the kbox itself you will see that sw2 (throttle) and sw1 (power) are probably set to 5 and 5 by default. If you are running 93 octane you can increase to 7 and 7 (this is what kleemann used for their power gain advertisement). Sw2 (throttle) can actually be set to 9 if you are running 93 octane (with 10%ethanol) but the car becomes a boost monster. I was told by kleemann not to use 8 or 9 on sw1 (power) unless you are running 95 or 100 octane because it will actually decrease power. Also, the folks (i spoke with corey) at kleemann usa are very helpful if you need someone to walk you through it. Adjusting the tune is easier than installing the harness, <10 min. Even if you dont want to change the tune, double check that the factory set it to 5 and 5, as my throttle setting (sw2) was actually set to 0! And my throttle response still sucked despite the piggy back (No signal amplification-they forgot to do it when they shipped it to me). Also, if you look at the installation instructions theres a photo off the kbox board with the settings at 0 (sw2) and 5 (sw1) so i think this is how kleemann ships the harness. I was getting 0-60 of 4.2sec with the old setting all day (using new gtech pro ss-has 1 ft rollout built in), but down to 4.0 sec with the more aggressive settings...
let me know if you adjust and do more runs
cheers

Pete400

The type of gas you are using is also critical. I am running Mobil 93 octane with 10% ethanol (in the midwest). So if you bump up the settings to 7 and 7 at least use this octane and make sure its not 20% ethanol.

Stimpgsx

My kbox came with a 5 and 5 setting . I run 93 octane w 10% ethanol all day. Im going to adjust the settings and take it back to the track and see what it does in the 1/4 mile. Thanks for the info! I aways wanted to play with the settings but when I called Kleemann when I first got it the person I spoke with advised against it. Maybe I put race gas and crank it up to 9 😈

Pete400

Awesome, looking forward to seeing the results! Once i weigh my car i will use the gtech pro to do some "dyno" runs to check wheel hp/tq curves with and without the tune. With the new settings my c400 feels stronger and more aggressive than my 2013 550i xdrive did... even on the highway.

Pete400

Quick question, were u applying the break launch technique (stall launch) when u ran the 1/4 mile?

Stimpgsx

Yeah, I hold the brake and hit the gas. I do it as soon as the first light comes on so I don't overheat the tranny. Then release the brake and launch on third yellow.

Pete400

Thanks for the info. Gonna try that out at the drag strip over the next month or so. Cheers

sean1.8t

Don't worry about the lights. Just focus on getting a good launch. Other than reaction time which doesn't mean anything, they don't start your time until your car starts to move.

l3it3r

Running with just ESP off or in dyno mode? Curious if there's a difference at the track...