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Jesse,

I think it does work. At least it felt like it when I tried.

IIIMBPIII

I thought it worked to but it could all be in my head!

SLK55R

okay replaced the belt ... I needed a longer one then the one I WAS using or the one supplied by Evosport. Obviously I couldn't use the Evosport one since I have a renntech supercharger.

Thats has been installed and my baby is running great. I've checked the pullies often and triple checked for wobble. Originally it looked like there was a tiny tiny bit of wobble on the crank pulley but I think it was more optical. Ryan and I both think it looks true.

The install went easy for the crank pulley.

The install of the evosport pulleys went well with the exception of the water pump pulley. This one didn't fit perfectly but Ryan was able to to make it fit. Ryan mentioned something like it was a minutely off and could use a bit more machining or something. Evosport if you want I'll be happy to give you Ryan's contact info and you can ask him yourself. I don't think this is a issue as it is on fine and working well.

The only thing I can tell so far is that the car seems to pull a bit harder on the mid to high end. I am still letting the car get used to these new pulleys.

I'll see if I can fit some time in to do a dyno next week. BTW would all this damn smoke up here affect a dyno run? Ncal has as ton of wildfires going on.

pedal ecu reset :

1. Turn the ignition key to the on (not start) position.

2. Press the gas pedal to the floor and hold for five seconds.

3. Turn the key to the "off" position (don't remove the key), then release the gas pedal.

4. Wait at least two minutes for ECU to reset.

https://mbworld.org/forums/w211-amg/148019-holy-crap-you-guys-sneaky-ecu-reset-works.html

E55 PWR

as long as you torque properly and ensure the pulley is sitting flush there shouldn't be any wobble. Its good to see you replaced the belt, always good thing to do while you are in there. Did you replace front crank seal? its always good ot do that while you are in there, if not thats fine but its usually better to do as much maintenance as you can while its up in the air.

SLK55R

no I didn't but I"ll do that next time I have to play around there. Thanks for the tip.

A' La F1

Got the pulley. Goes on Wednesday the 2nd ironically the day I go to court for a speeding ticket. It is a nice piece; made of billet aluminum. Spent 30 minutes polishing it - not sure why; I guess I just want to look like it is worth $500. That and my OCB... In any event, I'll let all know how it unfolds.

wawy

"Spent 30 minutes polishing it" That's what I would have done!

SLK55R

You polished it for 30 mins???

Heh heh

I tried to get dyno time today but my original shop was closed and all the other dyno shops, that are open on the weekends, didn't have time.

Dr. C36

That is officially the cleanest looking pulley I have ever seen

A' La F1

Yeah, buying mods is still cheaper than therapy. Barely...

blackbenzz

Anxiously awaiting dyno's!

SLK55R

Still trying to get dyno time ... I'm super busy and the dyno place isn't open on the weekends. They are fully booked up thursday ( I don't have work) and will give me a call if a spot opens up. (cross fingers)

Now butt dyno - I got to be honest I didn't feel that much initially only a little bit extra up top. I have to say now I think the ecu is finally getting used to the pulleys. I think the difference is actually pretty dramatic. I even removed the Xpipe (which should reduce my hp a little) and I think there is a pretty big positive change.

Heh I hope the dyno doesn't call my butt dyno a liar.

A' La F1

Got the AMS pulley installed and reset the ecu via the pedal method. Noticable differences are how the engine now idles; a bit smoother than before. Also when I shut the ignition off the engine seems to stop spinning much more quickly. I probably will not dyno the car, but the car is much more alive between 2,000 and 5,500 rpm. Slightly less engine vibration at speed, but that could be my imagination. I didn't weigh the AMS pulley or the factory pulley, but the AMS pulley is SUBSTANTIALLY lighter than the factory piece; simply due to it being aluminum vs. steel. Easily 50% to 60% lighter than the factory piece. Overall satisfied and with the mod and lives up to Abedin's claims.

Took about 2 hours of labor to install by my independent mechanic, who did a great job. I replaced the belt and nut. The crank seal was fine, so it was not replaced. I decided against the underdrive pulley kit for a number of reasons.

BTW, if anyone needs a good independent Mercedes/BMW mechanic in the South Bay area of Los Angeles, Peter Mardikian of Mardikian Automotive is absolutely fantastic 310-376-4906. He does all my normal service and installs any mods I buy; springs, brakes/rotors, pulley, shocks, alignments, etc. without the annoying questions/comments that usually come from mechanics installing mods. And he is cheap!

Dr. C36

Give it a week or so, once it really adapts fully. Glad to hear you like it. Its still the cleanest pulley ever even installed haha, 30min of polishing really paid off.

SLK55R

Okay bad news first ...

The bad news is that there is no good news.

Took the car into the dyno today. Same dyno that i used before ... temp is about 5 degrees hotter today.

These are the changes made since I dyno'd last :
Removed Xpipe
AMS Crank Pulley
Evosport Underdrive Pulleys
2 1/8s longer belt

The difference between my last dyno and today is about -15 RWHP and -6 RWTQ. Their is a loss of hp and torque across the whole pull. Once the car hits around 3500 rpm the difference gets larger and larger. What is more puzzling is that my Air/Fuel Ratio has climbed and I'm running lean. Good thing I run on 100 Octane all the time. No detonation so my current condition isn't dangerous. Previous dynos had my around 10 airfuel ratio at the end ... currently its around 13.

The AMS Crank pulley is the exact same diameter as the stock crank pulley. I will confirm with AMS shortly.
I believe the Evosport pulleys are NOT the same diameter. That is probably why the kit came with a belt. Since all these pulleys are on the same belt ... I think it is throwing things off the supercharger. I will confirm with Evosport that the 3 evosport pulleys are not the same diameter and require a different length belt.

I will be removing the Evosport Pulleys completely tomorrow and redynoing.

I will report numbers again next week.

E55 PWR

Removing X-pipe is a big no no, That gives you excellent top end scavenging effects as well as good mid range torque response. I dunno why you removed it but I would suggest putting that back in.

It may be the Evo sport pulleys interfering w/ SC b/c they are different diameters thereby causing SC to spin at different rate than it normally would. Are you sure belt is not slipping on supercharger pulley due to different diameter accessory pulleys?

Also what were atmospheric conditions, temp alone is not the only factor. Barometric pressure as well as humidity levels also play a factor. any pictures of dynos & A/Fs to help troubleshoot?

Furthermore, b/c AFs are off ECU may be pulling a serious amount of timing to compensate for the lean condition thereby robbing power. All possible scenarios.

SLK55R

It was removed because my car was just too loud.

We were thinking about perhaps belt slippage but that should make my A/F richer not leaner. I'm seriously thinking diameter is different and thats why next step is to first remove the evosport pulleys and dyno again.

Its pretty damn dry right now Don't have the baro pressure I"ll get that from the dyno shop. I have the dyno but I need to get an electronic copy.

If it was pulling timing I would think that I would start seeing it dump fuel and make it extremely rich. If anything it looks like it isn't pulling any timing at all. I'll data log the next pull but to be honest my timing doesn't look like it has changed much. I have a system that looks at timing almost realtime and I haven't noticed a change.

My thinking is to go back one at a time and see if we can tell. If the results are still negative after the switchback to stock pulleys (evosport removal) then I will switch back to stock crank pulley.

My thinking though is that just an Xpipe can not possibly be at least 15 rwhp. That doesn't make much sense.

E55 PWR

Don't underestimate the X-pipe. X-pipe on the NA 5.5L can make as big of a difference as 8whp (as proven on dyno, check W210 E55 sections for dyno), so on FI car could easily be double that, but either way something else has gone ary.

Furthermore. In theory since the underdrive kit is smaller diameter, that means the belt is shorter, and since it is shorter that could have some how caused the delicate ratio of supercharger speed to crank speed to have changed. In theory (it is possible) if its shorter that means that the supercharger is spinning faster (more boost), so more air is entering the cylinders thereby causing lean condition and ECU is over compensating via knock sensors and pulling timing or doing God knows whatelse to run as safe as humanly possible, thats the ECU's job. As soon as it senses knock it will immediately do the safest settings possible. You may not hear the detonation or knock itself with the naked ear, but the knock sensors are definitely doing their job (and are fare more sensitive than your ears) and cutting back on power to save the engine (regardless of octane, octane can only do so much, although I'm sure its helping a bit).

Your diagnosis is correct, undo accessory pulley kit, put the original belt back one and see how it performs with just the crank pulley. Then take further action if necessary.

I could be wrong but that is my analysis of the situation, hope that helps.

P.S. you might want to email both companies and get there input as well.

SLK55R

I've emailed both companies ...

One thing that you have wrong is that the belt is LONGER and the underdrive pullies are probably Bigger. I had to use a 2 1/8 inch LONGER belt with the Evosport Pullies than on stock underdrive pullies.

The only reason why it doesn't seem like the ecu is pulling timing is that I would expect it to run rich then. Also if it was really pulling timing I would expect a much larger drop in HP than 15 rwhp.

Btw thanks for your input!

The other reason why I don't think(15 rwhp loss) its from the removal of the xpipe is that when I went from Renntech Shorties to Supersprint Longtubes, Supersprint 100cell cats, and the Supersprint Xpipe, I only picked up around 10 RWHP.

Shouldn't a longer belt mean more boost?

E55 PWR

Just doing my best to help out.

Changing the belt can in theory change the way the SC behaves (either shorter or longer) I have a feeling that is whats making the impact.

Ahh I guess I am wrong in that regards (accessory pulleys), well in that case this may make more sense. If the pulleys are larger and the belt is longer that means per rotation of the crank pulley the SC pulley is spinning less. That would explain why the gap widens as rpms go up b/c the ratio is out of balance. That would mean less boost, hence lower HP. As to why the ECU is running lean... perhaps b/c it senses so much less air the ECU is cutting back fuel hence lean condition. Again this is all speculation, You have to realize that your setup is so rare that probably only a few on planet earth (if anyone else at all) is running your specific setup. Hats off for being brave enough to give it a shot.

Either way it seems the changing of the belt length has had an ill effect on your numbers. Do as you plan, remove accessory pulley kit and diagnose from there.

P.S. when you take off acccessory kit, reset ECU again and allow a few days to adapt again and then redyno to diagnose, that in theory should fix all your problems. I STILL recommend putting X-pipe back and perhaps getting a quieter catback muffler to compensate but again thats your choice.

A' La F1

I don't think lengthening the belt would affect the ratio of rotation between the crank and the s/c pulley. Only by changing the diameter of either pulley would affect the ratio of rotation. Think of it as a multi gear bicycle; adding one or two more links to the chain would not increase or decrease the revolution of the wheel per pedal stroke - the slack would be taken up by the derailleur (in your case the larger underdrive evosport pulley). I'm thinking the issue is with how the ecu was tuned with all the mods combined; removing the x-pipe may have bollocks up the tuning.

Let us know how it unfolds.

SLK55R

I think you're right on target ... we will see!

Thats definitely possible ... I didn't think of that.

Will do I won't be able to dyno until next week. The dyno place will be closed until then. The problem with the Xpipe is that it completely removes the resonator. On the SLK you have to make a choice of resonator or xpipe. The exhaust just isn't long enough for both. I'm thinking of maybe ordering the full Supersprint system to see. Last time I looked on their website they now have a resonator as well for sale. SS resonator + SS Mufflers might do the trick. But its a lot of money on a hunch ...

E55 PWR

Well in theory the pulley comment is true assuming the total belt diameter is constant, changing the pulley diameter would change the % boost. However if keeping both pulleys constant but changing the overall belt diameter could change the # of rotations of the SC pulley per rotation of the crank pulley. again just speculation it but is a possibility. That would be the only logical explination b/c the accesory kit is the only non stock diameter components, everything else (SC & crank pulley) are both "stock" diameter (not that the SC pulley is stock). Again only way to know is to do it.

E55 PWR

Honestly,

I think you really need to switch over to a Dyno Dynamics Dyno, it is far more accurate for tuning and troubleshooting than the dynojet is. Dynojet isn't going to be able to tell you exactly what happening at the rear wheels which is why I highly recommend you switch over and put it on a dyno dynamics dyno and see what it says.

dynojets are not very accurate, you might as well be using a G-tech. Put it on a DD and it will tell you everything you need to know when doing before & after dynos.

hope that helps

SL55_Forever

WARNING: Read This Before Buying AMS