Buellwinkle

It's just that I've seen things were tuners weren't very helpful. For example, look at Linh's Kleemann pulley, his car is running very lean, leaner than mine yet Kleemann hasn't been much help and he had to go to a Vaeth for assistance, this speak highly for Vaeth, helping out a Kleemann customer. Then you have WyattEarp, blew his S/C 4 days after a Kleemann ring, did Kleemann pay for the repair? I just don't see the value added and maybe Renntech is different than Kleemann, it's just that I can't limit my car to racing and off-road use only like my dirt bikes. And can ASP help you with these situations, no, they just make a pulley. It's the help from the forums that I count on the most, people that have gone through the good and the bad and can add real perspective. Afterall, that's how I find out about a lot of things MB won't tell me like the windshield fogging problem.

young

thanks boo2. actually, i don't feel bad about it. i'm very pleased w/ the end results and that's what matters to me the most.

btw, i'm sorry to drag this out...

edvpt

Lets see if we can get this thread back to something we can all get value from. Has anyone changed any of the fuel settings while using an after market pulley, any pulley?

Young I believe you went back to the default settings correct? Did the shop make any changes when they installed your ring?

If no, then we need to wait for Buells experience at his MB shop Dyno to see if there is a way to reduce the A/F ratio without chipping the car.

young

yes, renntech recommended that the fuel setting be changed to stage 2 or 3. i'm going to the dealer this friday to get it changed to stage 2 (as well as getting the vent changed and my door seal thing replaced).

Buellwinkle

I don't think Young has access to a dyno so it may have to wait afterall since I seem to be doing the testing for all the pulley companies since either they don't have the info or don't want to post the results for whatever reason (like it won't be public knowledge soon). What's made a big difference in the a/f ratio was no air filter. It went from an already too lean 14:1 to 15:1 at high RPM with no air filter. This concerns me as I have the ITG air filter on order as does Young. I want to do it all when the ITG filter comes in but it's not even in the U.S. yet but hopefully it will be this week.

renncpe

Lets see you have Dynoed one car with one change. That is hardly testing. I'm sure that Kleeman and I know for a fact that Renntech have run dynos in the hundreds. With changes to the ecu, air filter, pulley size, exhaust, plugs ect.

For others interested in Fuel settings I have been running at stage 3 for several months. I also have the octain setting to 93. I don't get 33.6 mpg and I don't expect too. I get 27- 28 most of the time.

Randy

Lynn

Part of the lower fuel economy can be attributed to Randy's lower rear gears.

renncpe

That is true and I need a long strech of road to get into the 27 mpg range. My everyday mpg ave around 16. I'm sure that my driveing style has alot to do with it.

Randy

linh

Then what exactly the $700 chip do? Since the fuel problem is fixed by setting it to stage 3. I'm sure you has dyno alot of car with Renntech pulley, do you mind or dare to post the hp/tq gain with A/F ratio?

linh

This came from one of the Renntech customer...........I'll say it again. Buy what ever you want to buy but just do yourself a favor by dyno your car to protect yourself.

young

linh, i don't understand what you're saying. did you or did you not have a lean A/F ratio? what is this apology to kleemann about? is it ok now w/ the upsolute chip?

i've been reading all the posts on the A/F ratio issue and here is sort of a summary of what i've been able to glean:

buellwinkle says (linh's slk) may be an older SLK issue b/c it uses a different ecu.

otoupalik says that there should be no a/f ratio issues w/ kleemann, renntech or carlsson that would require a "band-aid" solution of getting a chip.

otoupalik says, "If you simply put around to the grocery store and only stomp it once in a while, then 14 is not so outrageous." well, shamefully, that is me...

several people say that 14:1 A/F ratio isn't too bad.

bullwinkle says, "Yes, to me the A/F ratio is an issue but not a serious one..."

anyway, my conclusion is that the A/F ratio issue is not a serious one. the major manufacturers have it covered for the C-sportcoupe. by increasing the fuel quantity, changing the fuel octane rating, the A/F ratio should be even better (and so even less of an issue).

any comments?

ps what's your problem w/ renntech? that one guy's opinion is one guy's opinion. i've been treated very well by renntech. does that balance things out?

Brandon @ Kleemann

You cant be everything to everybody- ever. Any tuner is bound to have an experience with a customer who somehow feels as if they got the short end of the stick. All you can do is make all the good faith efforts you can to make it right.

As for oberklasse being recommended by MBZ themselves- well you would have to be a pretty big sucker to believe that. A small Texas retailer- recommended by MBZ Germany? Dont you think there would be just a FEW guys at AMG a little ticked off? If you go to oberklasse website it looks as if they are a MKB dealer- yet if you ring up MKB in Germany they'll tell you they ARENT an authorized dealer.

Some time ago one of my friends was trying to buy MKB headers from oberklasse-- FOR MONTHS-- before he finally found out the truth from MKB Germany- sound like gold to you?

Is this indicative of oberklasse as a business? No. There is always your story, and the other sides story- the truth lies somewhere in the middle.

BTW to the best of my knowledge Randy does not work for RennTech but BRUMOS- he takes quite a bit of S*** for a guy with no direct interest in RennTech other than selling the products to those who want them at his dealership. Hes an enthusiast with a preference (therefore bias) JUST LIKE EVERYINE ELSE here!!!!

linh

Young, i did make an apology to Kleemann because at the time i realize that the dyno shop way of recorded the A/F ratio was wrong. But last Friday i has my car dyno it again at Evosport shop and Vadim recorded the A/F ratio the same way as my last dyno shop did and the A/F ratio still show exactly the same. I question Vadim method of recording A/F ratio after the CAT. Vadim said that it does not make that much of a different. The only different is the delay of reading. Vadim also pointed out that the A/F ratio NEED to be between 12.0-13.0 !!!

That's what they made us believe is why i has A/F ratio problem because it not as adaptive ECU like in a newer model slk. We proved them wrong when we dyno Buellwinkle car with pulley and find out also has A/F ratio problem but not as bad as mine. I know for sure that Vadim has talk to Kleemann about the A/F ratio problem on the C-coupe after he dyno Buellwinkle car and realize that he saw two C-coupe with pulley and with high A/F ratio and now Kleemann is recommending changing the fuel setting to stage 3. I also know the dealer that did the changing for Vadim and Mark C.

Young, i did not say anything of what you what to buy, i just asked you to protect yourself by dyno your car. I'm actually helping because of my experienced.

young

i'm still a little confused. the mercedes mechanic, and another member, said that measuring the a/f ratio as evosport does (after the cat converter) is inaccurate. vadim@evosport says it is accurate...

i can only suggest getting a second opinion dyno at another shop that will do a measurement pre-cat and see if it corresponds w/ your previous a/f ratios.

and i know you are not telling me what to buy and your experience has brought up some issues and i learned quite a lot. i thank you for that.

linh

Young, you're not alone. I'm little confused just like you too...lol. My Vaeth fuel pressure regulator will be here on Monday and i'm trying to get another dyno at Vadim shop on Thursday of that week. This time i'll ask Vadim to measure the A/F ratio before the CAT for sure. He didn't do that the last time because the welder machine was broked. I really appreciated Vadim help alot. He offer free dyno to help me find a fix of my lean problem and i only meet him one time. So far i heard all the good thing about him from his customer. I has another chapter that i want to write to you guys about my last experienced but this is not the right time to talk about it yet. Let just say that i was really surprised when i see the result on the dyno. It nothing like what i felt. The "butt dyno" is wrong once again. You guys really need to dyno your car those with pulley regardless the manufacturer.

renncpe

That guy did not even buy anything from Renntech. He was pissed b/c he could not afford anything renntech sold for his C280. Like a rebuild or cams. ?????

Randy

avlis

My experience with other cars is to simply "back-probe" the O2 sensor connector to get a voltage reading. No need to weld on a O2 sensor fitting. Does the design of the MB connector prevent back-probing?

When I say "back-probing" (please, no _ _ _ _ish comments)- I mean inserting thin wires connected to the volt-meter into the back of the connector between the wire insulation and housing plastic.

Buellwinkle

I asked that and Vadims's tech said they had to put in a sensor that was compatible with their dyno. They did use a tail pipe sniffer instead on Linh's car. I don't think you get that much of a difference in readings either way.

Brandon @ Kleemann

The only problem with this method is the factory sensors range. The O2 in an MBZ cannot measure a 12.5:1 AF ratio- "narrow" band O2's measure between 17:1 and 13:1. If you back probe a standard O2 and see a high mv reading like 1150mv all that means is you are running a minimum of 13:1- you have no way of knowing if ists actually 11:1 as the mv returned from the sensor would be the same. Dyno O2 sensors are "wide" band units that CAN measure sickingly rich mixtures.

Measuring POST cat will most certainly effect the indicated AF. A cats job is to convert CO, among other things, to less harmful gases. The O2 sensor is comparing the ex stream to outside air- so if you "clean" the ex stream to nearer ambient air it appears leaner than it is. How much this method sckews results is a topic of much debate.

Any workshop manual procedure to verify mixture will always sample CO % ahead of any CAT.

linh

I'll take your words for it on that matter. But Renncpe, so what exactly $700 chip do when you can take care of the fuel problem by having the dealer do the setting to stage 3?

renncpe

Linh Stage 3 does not do anything beyond letting the engine get a richer mixture at idle and WOT and warm up. The reprogramming of a chip does much more than that. I really can’t go into it more b/c it is very involved and I do not even know all the systems that are effected by the reprogramming, but it does go much further than fuel and timing.

Randy

linh

What, my car "stock" dyno show A/F ratio at 11.5 - 13.0 and the reading were measure after the CAT.

Brandon @ Kleemann

linh-

Read the post Im answering again- What Im saying is the O2 sensor IN THE CAR cannot measure a AF ratio like 12:1. If you took your car to a dyno and they used the dyno AF ratio meter it undoubtedly had a wideband O2 that CAN measure that ratio.

linh

I understand it now. which mean i can't hook up the A/F ratio gauge to the factory O2 sensor to monitor my A/F ratio, Because it only read A/F ratio from 13.0 and up right?

Brandon @ Kleemann

Correct!