Pulley Mod Question
Thread Starter
Senior Member
Joined: Jul 2003
Posts: 460
Likes: 14
2006 SL65 ///AMG - GONE BUT NOT FORGOTTEN: 2005 E55; 2002 ML55; 2001 CLK55; 1992 BMW 850i; 1991 M5
Pulley Mod Question
Has anybody out there had a bad experience with overdriving the SC pulley on their car with either the RennTech or Kleeman kit? This seems to be a very popular mod and I'm just wondering if there are any pitfalls to be aware of like increased heat, increased detonation with greater boost, noticable wear on bearings, engine internals, etc? I had considered doing the RennTech ECU mod and throttle body without the pulley, but the RennTech guys discourage skipping the pulley, as that is where most of the power increase from the upgrade apparently comes from. I was hoping that more aggressive ECU mapping and a bigger throttle body might get me to SL55 figures (500ish) without tweaking the main SC pulley. Any and all thoughts are welcome and appreciated!
Senior Member
Joined: Mar 2004
Posts: 385
Likes: 1
From: Palm Beach Gardens, Fla.
2004 E55
It's fairly well known that the drivetrain of these cars can handle upwards of 750+ hp and tq!! That includes all the internals of motor and tranny! To tweak these up to the mid 550'ish range is a non-issue and with all the Renntech's and K2's running on this forum, I have yet to hear of one related "added boost" failure.
Recommend the full Renntech or K2 upgrade - you'll be happy you did!
Recommend the full Renntech or K2 upgrade - you'll be happy you did!
Thread Starter
Senior Member
Joined: Jul 2003
Posts: 460
Likes: 14
2006 SL65 ///AMG - GONE BUT NOT FORGOTTEN: 2005 E55; 2002 ML55; 2001 CLK55; 1992 BMW 850i; 1991 M5
Thanks!
Thanks, Ken. That's what I needed to hear. BTW, is there any real HP to be gained behind the cats on these cars? I have considered swapping the center resonator for a Supersprint unit and swapping the rear cans for Eisenmanns, but I wonder if this is a purely cosmetic - audio upgrade with no real hp benefit.
Senior Member
Joined: Jan 2005
Posts: 336
Likes: 0
From: Singapore/Central London UK
E63 biturbo
Originally Posted by PDC
Thanks, Ken. That's what I needed to hear. BTW, is there any real HP to be gained behind the cats on these cars? I have considered swapping the center resonator for a Supersprint unit and swapping the rear cans for Eisenmanns, but I wonder if this is a purely cosmetic - audio upgrade with no real hp benefit.
For significant hp gains, u need to change the headers as well.
Joined: Jul 2006
Posts: 6,761
Likes: 594
From: Seattle
'19 E63S, ‘16 CLS63 RIP, '09 E63 Gone, '06 M5 Gone, '97 Supra TT Gone
One thing you won't hear a lot of people telling you is that the M113 is a heat-pig of an engine and increased boost only makes it worse. If you're going to overdrive the supercharger pulley I'd highly recommend an intercooler mod to go along with it. The issue lies in the inherent design flaw of sandwiching the intercooler between the supercharger and the engine 
, one of the thinge that the McClaren guys threw out the window right away with the M115. Its a horrible idea from an efficiency standpoint, when you think about the fact that most intercoolers are mounted on the front of an automobile in order to maximize the cooling effect of air being thrown at the front of the car. Now contrast that with an intercooler that has the heat from a supercharger bearing directly down on it and the heat from an unforgiving manifold right beneath it. Total nightmare.
, one of the thinge that the McClaren guys threw out the window right away with the M115. Its a horrible idea from an efficiency standpoint, when you think about the fact that most intercoolers are mounted on the front of an automobile in order to maximize the cooling effect of air being thrown at the front of the car. Now contrast that with an intercooler that has the heat from a supercharger bearing directly down on it and the heat from an unforgiving manifold right beneath it. Total nightmare.
Senior Member
Joined: Mar 2006
Posts: 333
Likes: 0
From: Berkeley, California
2005 E55, Renntech Pulley, ECU
~10k with the Renntech pulley+ECU upgrade with no complaints. I do have the occasional 'surge' at low RPM, but that looks like it is related to that ECU upgrade they did a few months back. I did the pulley+ECU thing the next day, but I'm confident it isn't related based on other folk's complaints.
LOVE the increase in power. I would definitely do it again were I to buy a newer E55 with less miles (I'm in a 2005 with 30k).
Go for it,
Skeeter
LOVE the increase in power. I would definitely do it again were I to buy a newer E55 with less miles (I'm in a 2005 with 30k).
Go for it,
Skeeter
Trending Topics
MBWorld Fanatic!
Joined: May 2006
Posts: 3,042
Likes: 0
From: So.Ca.
E55
What about running the pulleys but no ecu change? If you run the pulleys,how much hp is gained by doing the ecu also? Not sure but didn't I read on here that these cars can handle the pulleys and not have to have the ecu done,as long as the a/f is ok across the board.Is it possible to add the pulleys,drive the car for a short time to let the ecu adjust and then make a few dyno pulls to check the a/f's?
Have any of the tuners been able to correct the "load limiting' problems yet?
Have any of the tuners been able to correct the "load limiting' problems yet?
MB World Stories
The Best of Mercedes & AMG
8 Oddball Mercedes Ideas That Actually Made it to Production
Verdad Gallardo
Dubai Tuner Gives the Mercedes G-Class An Entirely New Look
Verdad Gallardo
Six Gift Ideas Your AMG Loving Dad or Grad Will Cherish
7 Craziest Things AMG Gas Ever Built
Verdad Gallardo
New Electric Mercedes-AMG GT 4-Door Coupe Unveiled: 10 Things You Need to Know
Verdad Gallardo
6 Mercedes Models That Did NOT Age Well (But Are Somehow Still Cool)
Verdad Gallardo
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun
Verdad Gallardo
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Verdad Gallardo
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine
Verdad Gallardo
MBWorld Fanatic!
Joined: Jun 2006
Posts: 1,264
Likes: 0
From: Long Island & Hong Kong
20+ to list......
Definitely go for the pullies, I am getting them ordered through Matt @ Powerchip, great guy, been very helpful on my European collections. Our motor is known to generate **** load of heat, to remedy it, you will need EVOSport cooling package. Some members on the board are running -10c fan mod and 160F thermostat, which help also.
