PDC

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!

Kens-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!

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.

Jspeed

For significant hp gains, u need to change the headers as well.

dsc

10,000 miles with the K2. No problems to date. If you don't do the headers forget the rest of the exhaust. Headers and remove primary cats give the most gain. It's included with the K2.

Cylinder Head

iTrader: (1)

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.

Skeeter

~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

Jrocket

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?

2MANYCARS

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.