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Discussion Starter · #1 ·
Do you guys know where I can find one. LET does not have it on their site anymore (just the sc pulley) and I would rather do the crank pulley kit. Any suggestions?
 

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Do you guys know where I can find one. LET does not have it on their site anymore (just the sc pulley) and I would rather do the crank pulley kit. Any suggestions?
I'm no a fan of the ASP pulleys because they are based on the stock rubber damper design, which has a high failure rate. The LET pulleys are now sold by a sister company called EuroCharged Performance. They have both the 181 and 185 mm LET pulleys. They're not listed under the SLK32 section (which needs updating), but they are the same as the C32 and SRT-6 pulleys (among other parts). Check out the C32 parts here:
EuroCharged Performance- Mercedes, BMW, and Chrysler Performance Parts and Tuning

The owner's name is Jake and posts frequently on the C32 board. I'm sure you know you'll need a LET tune with the new pulley. /Craig
 

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Discussion Starter · #4 ·
I'm no a fan of the ASP pulleys because they are based on the stock rubber damper design, which has a high failure rate. The LET pulleys are now sold by a sister company called EuroCharged Performance. They have both the 181 and 185 mm LET pulleys. They're not listed under the SLK32 section (which needs updating), but they are the same as the C32 and SRT-6 pulleys (among other parts). Check out the C32 parts here:
EuroCharged Performance- Mercedes, BMW, and Chrysler Performance Parts and Tuning

The owner's name is Jake and posts frequently on the C32 board. I'm sure you know you'll need a LET tune with the new pulley. /Craig
Thanks for all the info! I really did not want to use the ASP pulley for the same reasons and I am planning on doing the 185mm with the tune. I am just trying to decide if I want to tackle new headers at the same time. The install for the headers looks like it will be a pain though and hate to pay someone to do it, just have to see if I can find the time.
 

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2002 SLK 230 1986 560SL 2008 Honda CRV
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After looking at the LET pullies i would not buy one for the simple fact that its a ring and is held on with set screws, not the most secure way to install a pulley. I've been told by other's that if those set screws let go the danage could be very expensive.
 

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2002 SLK 32 AMG, bone stock. 1987 190E 2.3-16 valve (destroyed). 2005 E320 new toy.
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Headers haven't proven themselves to give much of an increase in power for their cost, although there is a slight gain. You have to determine if the cost/benefit ratio is worth the effort.

While it is true that if the set screws come out on a pulley set up serious damage can occur, this kind of installation is not unknown in heavy industrial applications. The engineering and machining of the parts are what will determine how well this kind of set up works. If red Loctite is used on the set screws you can be assured that they will not come out without high heat being applied. I would be more concerned about how concentric and true running the pulley is after the ring is installed, that to me is the real test.
 

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Do not use a solid aluminum pulley, you are asking for trouble. But if you really want one, ask Lee ([email protected]), he'll make you one for about $300 if you sign a waiver because he's had too many problems with them and recalled them.

Also, don't buy a ring that's attached with set screws, it's not that they back out, it's because it's not true and not balanced. I've seen just about everyone with a 2.3L M111 motor have to replace their S/C because of this. One person was a die hard, a popular guy on the C forum and he did not give up, he put in 3 s/c before going to a different design. Also, I would imagine that over time, the steel set screws in aluminum against the sharp edges of the pulley grooves would wear from vibration further causing the pulley to shift in place and be less true. BTW, this was actually Lee's first design and after playing with it, he chucked the idea before I even had a chance to test it.

They also make it for the SLK32/C32 motor.

The problem with the SLK32/C32 is the IC is not that effective, some have made larger tanks for improving cooling and that gives you more power.

I feel I know more than most since I worked on the different designs 7 years ago and with a few hundred of these out there, they've been proven in the field, how many SLK230 pulleys has LET sold? ASP tried 2 other designs before this one, a solid aluminum, aluminum with steel hub and finally a factoy pulley with a pressed on and welded steel ring and it's rebalanced. He charges a very fair $650 that includes a $300 core charge, return the old pulley and it only costs $350. Of course if you have a 1998-1999, you will need the other stuff (fpr, plugs, maf relocation) so it's more.

1. When you replace the steel with aluminum you typically increase the thickness of the metal to get equal strength. The problem is the hub thickness is fixed, you can't make it thicker or thinner. So this has been a failure point where the hub can crack. Some pulley companies mitigated the issue with a steel hub attached to a aluminum pulley but over time, there's a good chance that the different metals working against each other under high stress will cause the holes to enlarge and wobble.

2. The crankshaft has a difficult job, it has to take the up and down motion of the pistons and transfer that into a rotating motion. The start and stop of the pistons causes the crankshaft to absorb a slight twisting motion and that is absorb by the damper, so having a solid pulley can cause your crankshaft to wear prematurely.

3. It's a myth that a lighter crank pulley will give you better performance. I dyno tested many configurations for ASP and another pulley company and there's zero difference between an aluminum pulley and steel. Why? Simple, because the few pounds of rotating mass you save with an aluminum crank pulley is nill compared to the rotating mass on the other end of the crankshaft, namely your tranny, driveshaft, axles, wheels, tires, etc.

I can certainly understand if you don't like ASP, not everyone is loved the same, but honestly, if ASP went out of business and I wanted another pulley, I would get a Vaeth from Germany. Think of it this way, about 8 well regarded tuners like Brabus, Renntech, Carlsson, Vaeth, Opera Design, use a factory pulley to make their pulleys, yet they can make $300 more per pulley if they just made a cnc machined aluminum pulley. So who you bet your engine on, these MB tuners, or LET?
 

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someone please educate me. with all the different opinions and pros and cons about crank pulleys wouldnt it be safer and easier to change the s/c pulley?
 

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someone please educate me. with all the different opinions and pros and cons about crank pulleys wouldnt it be safer and easier to change the s/c pulley?
There are a couple of issues involved in trying the change the sc pulley. There is the problem with the "nose" but the biggest issue is that you would have to make it SMALLER....and fyi...anytime you make a belt turn a smaller, tighter bend, you greatly increase wear on the assocated belt. There are a couple of guys that make a kit for doing it but after weighing the pros and cons, I elected not to do it. When I bought my car I had about $5,000 to throw at performace mods....I ended up only getting a crank pulley(from JDS in Texas..same pulley as asp, just a lot cheaper) and a custom chip program to move the power to the upper rpm range since there is plenty of torque in the stock engine design. This was selected to work in concert with the faster spinning sc(from the new crank pulley). Also a K&N....total gain, probably 20hp although each of the reps say THEIR part produces 20-25hp...and I have a bridge to sell you<LOL>.....overall the car has never broke(other then my ignition lock), no cel's and a reasonable bump in performance. It was never built to be a zero to 60 rocket but heck, it'll do an honest 150+ so I'm happy.


When I get the urge to do the 0-60 thing, I have a garage full of motorcycles that more then cover the bill....and they are a lot cheaper!!


Good luck!

Jeff
 

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someone please educate me. with all the different opinions and pros and cons about crank pulleys wouldnt it be safer and easier to change the s/c pulley?
As Jeff mentioned the belt flexure is a problem, but the smaller contact area on the smaller pulley would require higher belt tension to transmit the same amount of power without slipping. You will want to transfer more power, and the belt slippage really becomes a problem as does the added load on the bearings because of still higher bent tension. Timing belts look like a good alternative over the serpentine belts in this situation.
 

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There are a couple of issues involved in trying the change the sc pulley. There is the problem with the "nose" but the biggest issue is that you would have to make it SMALLER....and fyi...anytime you make a belt turn a smaller, tighter bend, you greatly increase wear on the assocated belt. There are a couple of guys that make a kit for doing it but after weighing the pros and cons, I elected not to do it. When I bought my car I had about $5,000 to throw at performace mods....I ended up only getting a crank pulley(from JDS in Texas..same pulley as asp, just a lot cheaper) and a custom chip program to move the power to the upper rpm range since there is plenty of torque in the stock engine design. This was selected to work in concert with the faster spinning sc(from the new crank pulley). Also a K&N....total gain, probably 20hp although each of the reps say THEIR part produces 20-25hp...and I have a bridge to sell you<LOL>.....overall the car has never broke(other then my ignition lock), no cel's and a reasonable bump in performance. It was never built to be a zero to 60 rocket but heck, it'll do an honest 150+ so I'm happy.


When I get the urge to do the 0-60 thing, I have a garage full of motorcycles that more then cover the bill....and they are a lot cheaper!!


Good luck!

Jeff
The pulley that you are talking about from jds, I'm assuming jdsperformance dot com, that you claim is alot cheaper is only 33 dollars cheaper than ordering straight from asp. I would like to know if they give you the 300 back when you send them your stock pulley like asp does. If not, then asp would be way cheaper. In the end being only 350 as opposed to 617
 

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thanx fellas. i never stop being amazed at the wealth of info to be had from this forum!
 

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Do not use a solid aluminum pulley, you are asking for trouble. But if you really want one, ask Lee ([email protected]), he'll make you one for about $300 if you sign a waiver because he's had too many problems with them and recalled them.

Also, don't buy a ring that's attached with set screws, it's not that they back out, it's because it's not true and not balanced. I've seen just about everyone with a 2.3L M111 motor have to replace their S/C because of this. One person was a die hard, a popular guy on the C forum and he did not give up, he put in 3 s/c before going to a different design. Also, I would imagine that over time, the steel set screws in aluminum against the sharp edges of the pulley grooves would wear from vibration further causing the pulley to shift in place and be less true. BTW, this was actually Lee's first design and after playing with it, he chucked the idea before I even had a chance to test it.

They also make it for the SLK32/C32 motor.

The problem with the SLK32/C32 is the IC is not that effective, some have made larger tanks for improving cooling and that gives you more power.

I feel I know more than most since I worked on the different designs 7 years ago and with a few hundred of these out there, they've been proven in the field, how many SLK230 pulleys has LET sold? ASP tried 2 other designs before this one, a solid aluminum, aluminum with steel hub and finally a factoy pulley with a pressed on and welded steel ring and it's rebalanced. He charges a very fair $650 that includes a $300 core charge, return the old pulley and it only costs $350. Of course if you have a 1998-1999, you will need the other stuff (fpr, plugs, maf relocation) so it's more.

1. When you replace the steel with aluminum you typically increase the thickness of the metal to get equal strength. The problem is the hub thickness is fixed, you can't make it thicker or thinner. So this has been a failure point where the hub can crack. Some pulley companies mitigated the issue with a steel hub attached to a aluminum pulley but over time, there's a good chance that the different metals working against each other under high stress will cause the holes to enlarge and wobble.

2. The crankshaft has a difficult job, it has to take the up and down motion of the pistons and transfer that into a rotating motion. The start and stop of the pistons causes the crankshaft to absorb a slight twisting motion and that is absorb by the damper, so having a solid pulley can cause your crankshaft to wear prematurely.

3. It's a myth that a lighter crank pulley will give you better performance. I dyno tested many configurations for ASP and another pulley company and there's zero difference between an aluminum pulley and steel. Why? Simple, because the few pounds of rotating mass you save with an aluminum crank pulley is nill compared to the rotating mass on the other end of the crankshaft, namely your tranny, driveshaft, axles, wheels, tires, etc.

I can certainly understand if you don't like ASP, not everyone is loved the same, but honestly, if ASP went out of business and I wanted another pulley, I would get a Vaeth from Germany. Think of it this way, about 8 well regarded tuners like Brabus, Renntech, Carlsson, Vaeth, Opera Design, use a factory pulley to make their pulleys, yet they can make $300 more per pulley if they just made a cnc machined aluminum pulley. So who you bet your engine on, these MB tuners, or LET?
OK, first of all, this thread was about a larger pulley for the M112 engine in the SLK32. This thread seems to have wandered off into the weeds.

A non-dampened pulley is not recommended, period, aluminum or steel. Go to the C32 and SRT-6 boards, and NO ONE uses an aluminum pulley on the M112 SC motor.

The LET pulleys are mechanically dampened, so they have to be assembled with fasteners. They aren't a simple ring bolted to a hub. And they are balanced. The factory MB pulleys on the M112 motor are cheap and they SUCK, so I really don't understand the reference to MB and "branded" MB tuners other than to say you are underestimating their profit margin. LET is a bona fide MB tuner. But the reality is those rubber dampened pulleys have been demonstrated to fail prematurely and often, and when they go they cause serious damage. Moreover, they get out of balance quickly and become more and more unbalanced as they fail.

On the issue of inadequate intercooler cooling, you are absolutely correct: the factory design is limiting without mods and needs to be corrected to realize the real output available from the engine once things heat up. Up the boost and it gets even hotter, so increased cooling becomes mandatory. Change the IC pump to a Johnson, replace the factory heat exchanger with a larger core underneath or a radiator-style core stacked in front, and separate the engine cooling circuit from the IC circuit with a separate expansion tank. Some have gone to a new IC as well (e.g., Spearco unit from Code 3), although the jury is still out on whether that mod is really giving back much. If you want to solve that issue you really need to replumb the intercooler to lie outside the engine IMO. But when you're looking for relief from a bottleneck, any improvement is usually welcome for some folks.

On the issue of a smaller SC pulley raised in another post, Code 3 has demonstrated respectable gains without significant belt slip problems. I have had one of these on my car now for about 8,000 miles and it works quite well. When people started stacking pulleys and going to really large crank pulleys like the 185, belt slip started rearing its head. Code 3 makes a pulley wrap kit that addresses belt slip for smaller SC pulleys, and I understand that EuroCharged Performance is working on a belt wrap kit that addresses the larger crank pulley. The most common mistake is to not replace your serpentine belt when you go to a new pulley. Note also that the charge plenum gaskets leak notoriously under boost, even stock, so it's advisable to replace these with material that's more reliable than the stock gaskets. You might check out the plenum gaskets from NeedsWings to fix that issue.

My two cents.

Craig
 

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Craig,

I own a 2003 SLK 230 and have ran a ASP Racing crank pulley for over 40K miles now without a hickup. I have been a member here for more than a few years and never remember reading one post about one ASP Racing pulley failing. Maybe it is just me but I might have missed those threads but I kinda doubt it.

My good friend 430 has done most of the cooling mods you have refered to and might be the guy you are using as a reference. I am curious as to what mods you have done to your car. You seem to have some good info for the SLK 32 and I know enough about the SLK 32 to know you are legit but it seems to me you are wrong when it comes to the ASP crank pulley for either the SLK 230 or the SLK 32. I just have not heard of any failures. From my expierence the ASP pulley has been amazing. Do you own an after market crank pulley or blower pulley for the lysholm?

Done any of the cooling mods or just going by what others have done?
Steve,

I do not presume to know much about 230s or 230 mods. But even 430 has posted an ASP pulley failure himself:

http://www.benzworld.org/forums/3128783-post21.html

I have to conclude that forces acting on the 230 crank are not as severe as those on the 320 crank. I'm sure that you are aware there was a factory recall on the C32 and SLK32 crank pulleys -- not on all, but a couple of years; and quite a few outside the recall have failed as well (mine included, at around 20,000 miles). I am not saying that the ASP pulleys all fail nor that I have direct experience with the ASP pulleys; but I am saying that the design has proven to be suspect if not unreliable for the M112 AMG motor.

Regarding pulleys and cooling, I currently have a first gen Code 3 SC pulley and intake mod, a LET stage 1 tune, a Johnson IC pump and LET heat exchanger. I have also purchased but not yet installed a Meziere expansion tank to separate the cooling circuits.
 

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Discussion Starter · #16 ·
Do you guys recommend upgrading the cooling system at the same time as the pulley? Is it safe to run the pulley without doing so? Has anyone run water injection with this motor?

Thanks,
Danny
 

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Do you guys know where I can find one. LET does not have it on their site anymore (just the sc pulley) and I would rather do the crank pulley kit. Any suggestions?
we updated the site....thanks for the catch...


I'm no a fan of the ASP pulleys because they are based on the stock rubber damper design, which has a high failure rate. The LET pulleys are now sold by a sister company called EuroCharged Performance. They have both the 181 and 185 mm LET pulleys. They're not listed under the SLK32 section (which needs updating), but they are the same as the C32 and SRT-6 pulleys (among other parts). Check out the C32 parts here:
EuroCharged Performance- Mercedes, BMW, and Chrysler Performance Parts and Tuning

The owner's name is Jake and posts frequently on the C32 board. I'm sure you know you'll need a LET tune with the new pulley. /Craig

thanks craig. We have updated the SLK section, sorry for the screw up. We have seen a lot of failures from the rubber damper design. Thats why we went with the mechanical dampening design.


Thanks for all the info! I really did not want to use the ASP pulley for the same reasons and I am planning on doing the 185mm with the tune. I am just trying to decide if I want to tackle new headers at the same time. The install for the headers looks like it will be a pain though and hate to pay someone to do it, just have to see if I can find the time.
Header install is really not too bad at all. On the passanger side you need to put one of the bolts through as you put the header on but the rest is pretty simple. We do a couple a month in the shop with our new headers.


Headers haven't proven themselves to give much of an increase in power for their cost, although there is a slight gain. You have to determine if the cost/benefit ratio is worth the effort.

While it is true that if the set screws come out on a pulley set up serious damage can occur, this kind of installation is not unknown in heavy industrial applications. The engineering and machining of the parts are what will determine how well this kind of set up works. If red Loctite is used on the set screws you can be assured that they will not come out without high heat being applied. I would be more concerned about how concentric and true running the pulley is after the ring is installed, that to me is the real test.
Red locktite is DEFINATELY used throughout the pulley. All pullies (E55, C32) are sent to a lab and ballanced accordingly before shipment if needed. We have the same worries that you would... Our headers are actually putting out some decent power, but agreed that type of thing is definately something that is to each their own.


OK, first of all, this thread was about a larger pulley for the M112 engine in the SLK32. This thread seems to have wandered off into the weeds.

A non-dampened pulley is not recommended, period, aluminum or steel. Go to the C32 and SRT-6 boards, and NO ONE uses an aluminum pulley on the M112 SC motor.

The LET pulleys are mechanically dampened, so they have to be assembled with fasteners. They aren't a simple ring bolted to a hub. And they are balanced. The factory MB pulleys on the M112 motor are cheap and they SUCK, so I really don't understand the reference to MB and "branded" MB tuners other than to say you are underestimating their profit margin. LET is a bona fide MB tuner. But the reality is those rubber dampened pulleys have been demonstrated to fail prematurely and often, and when they go they cause serious damage. Moreover, they get out of balance quickly and become more and more unbalanced as they fail.

Craig
I would never put a non-dampened pulley on my car period. Our pullies are very complex, including many pieces for the dampener. But, if we weren't a real tuner, then we wouldn't be putting up better numbers on tunes from kleeman and the like and we woulnd't have the fastest C32's out there.


Do you guys recommend upgrading the cooling system at the same time as the pulley? Is it safe to run the pulley without doing so? Has anyone run water injection with this motor?

Thanks,
Danny
It is safe to run without upgrading the cooling system. But, if you are running the car at the track you will suffer from heat soak which will rob you from your much needed HP
 

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Discussion Starter · #18 ·
I track my cars about twice a year so I am not to worried about heat soak for the immediate future, but I do drive my cars fairly hard on the street. From a reliability stand point would I be better off running with 178 or 181mm pulley instead of the 185? My goal is to push the car as far as I can without making it a lot less reliable.
 

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I track my cars about twice a year so I am not to worried about heat soak for the immediate future, but I do drive my cars fairly hard on the street. From a reliability stand point would I be better off running with 178 or 181mm pulley instead of the 185? My goal is to push the car as far as I can without making it a lot less reliable.
I have 30k on my 185 without issues. Go for the bigger power, you will regret it if you don't.
 

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Supercharger!!

Hi
I´ve very questions about pulleys, first of all, I´ve talked with a guy who told me they have a 225mm pulley, ecu upgrade, bigger ic, k&N, and the car have 255hp!!Can it is possible?Second when i put the bigger crank pulley i need to change the alternator pulley??How much psi/bar the car (slk230kompressor) done stock and with let pulley 185mm??
 
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