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Discussion Starter #1 (Edited)
Well I have stacked a 178mm crank pulley and a 70mm SC pulley. It seems the guys who stack the 178/65 have to many fuel/tuning issues so I did some research and the stock SC does not stay efficient above 15,000rpm. Divide the crank pulley by the SC pulley size and then multiply by the max engine rpm's. In my case 178/70=2.5428...x 6200rpm equals 15,765rpm. Yes a bit over, just the last few hundred rpm. I also added the pulley saver kit. Then a PLX wideband, one of the best, very accurate. Of course an SL55 fuel pump, used from ebay for $80. shipped rather than the $380. for a new one. A free flowing filter for under $20. shipped and NW's adjustable fuel pressure regulator. I have not logged the boost but estimate it to be around 20psi, maybe 20.5. With stock injectors.
Part throttle response is much quicker with the larger crank pulley turning the smaller than stock SC pulley sooner than if I had a stock pulley or even the 65mm SC pulley I had. Now for a throttle response enhancer and it will drive my sister nuts when she drives the car!

Maybe the ported lower "Y" pipe and tweaked intakes before I call it as these cars have their limitations. JBANKS15 go for a turbo, limitless power and a lot less than what Mercedes wants for the SC!
 

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Discussion Starter #4
I would be very interested in seeing the Dyno results.
So would I. Remember a dyno is a TUNING tool and the numbers mean little compared to other cars on a different machine. I'll try the shop in Sarasota that never got back to me with an estimate on the pulley/wideband/fuel mods. He has a Dyno. I am thinking 370 maybe after the "Y" and tweaked intakes. If I could swing it a dyno tune by Jerry done remotely would be cool if he could find another 20whp, actually 20wtq. HP means very little on these cars as they make peak HP at redline where it but useless. Torque is what moves the car and a nice fat torque curve with over 300wtq for 3000rpm would be nice. Boostmonkey has made over 400wtq and whp on the dyno but has only ran a 11.85 if I remember correctly. If I am off by a lot I apologize. For what he has done I would expect better times. One guy with just the DCAI, 65mm pulley and a tune has many runs in the 11's, many as low as 11.65 on a 50* night in Orlando.
I'll call and see about a few dyno pulls where I can at least adjust the AFR if not the timing also.
If my sister is in the car and I speed up to get through s yellow she screams at me. If I drive 37 in a 40 I get it for going too slow so she drives. Sprint Booster would be worth it to see the look on her face should she need to speed up to make a yellow>:D
 

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So would I. Remember a dyno is a TUNING tool and the numbers mean little compared to other cars on a different machine. I'll try the shop in Sarasota that never got back to me with an estimate on the pulley/wideband/fuel mods. He has a Dyno. I am thinking 370 maybe after the "Y" and tweaked intakes. If I could swing it a dyno tune by Jerry done remotely would be cool if he could find another 20whp, actually 20wtq. HP means very little on these cars as they make peak HP at redline where it but useless. Torque is what moves the car and a nice fat torque curve with over 300wtq for 3000rpm would be nice. Boostmonkey has made over 400wtq and whp on the dyno but has only ran a 11.85 if I remember correctly. If I am off by a lot I apologize. For what he has done I would expect better times. One guy with just the DCAI, 65mm pulley and a tune has many runs in the 11's, many as low as 11.65 on a 50* night in Orlando.
I'll call and see about a few dyno pulls where I can at least adjust the AFR if not the timing also.
If my sister is in the car and I speed up to get through s yellow she screams at me. If I drive 37 in a 40 I get it for going too slow so she drives. Sprint Booster would be worth it to see the look on her face should she need to speed up to make a yellow>:D
1/4 ET is much more driver (and traction) dependent than trap speeds - should compare those instead
 

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Discussion Starter #6
Got a couple of datalogs. Max boost 20.6psi with 25* of timing. Stacking nthe pulleys has been the best mod I have done as I get the 6.6% increase in boost at any rpm! response is instant and the pull hard and smooth!
 

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Well I have stacked a 178mm crank pulley and a 70mm SC pulley. It seems the guys who stack the 178/65 have to many fuel/tuning issues so I did some research and the stock SC does not stay efficient above 15,000rpm. Divide the crank pulley by the SC pulley size and then multiply by the max engine rpm's. In my case 178/70=2.5428...x 6200rpm equals 15,765rpm. Yes a bit over, just the last few hundred rpm. I also added the pulley saver kit. Then a PLX wideband, one of the best, very accurate. Of course an SL55 fuel pump, used from ebay for $80. shipped rather than the $380. for a new one. A free flowing filter for under $20. shipped and NW's adjustable fuel pressure regulator. I have not logged the boost but estimate it to be around 20psi, maybe 20.5. With stock injectors.
Part throttle response is much quicker with the larger crank pulley turning the smaller than stock SC pulley sooner than if I had a stock pulley or even the 65mm SC pulley I had. Now for a throttle response enhancer and it will drive my sister nuts when she drives the car!

Maybe the ported lower "Y" pipe and tweaked intakes before I call it as these cars have their limitations. JBANKS15 go for a turbo, limitless power and a lot less than what Mercedes wants for the SC!
What pulleys did you use and where can they be bought? I'm a new owner and itching to get some performance mods done once I get the car up to par. I actually didn't realize that this kind of power was possible from these cars.

Anyone know what size the blower is? Any data on it? You say it is efficient to 15k but do you or anyone have any intake air temps post supercharger? I'm concerned about heat generated.

What size are the stock injectors?

Also who/ where tunes these and what kind of software is used? Is it customizable or a handheld with set parameters?

I planned on actually turbo swapping it but if those numbers are easily achievable I may stick with the supercharger.



Sorry for all the questions.......thanks!!!!
 

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Mark will answer but remember he has an SLK 32 AMG. That is 6 cylinders with a Kompressor and 349 hp stock and a hand built engine

you know already what you have. Pullies probably are the best you can do.
 

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I am interested in upgrade pulleys, too. Where are they and how much do they cost? What kind of difference do they make?
I own a 2003 SLK32 AMG
 

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Mark will answer but remember he has an SLK 32 AMG. That is 6 cylinders with a Kompressor and 349 hp stock and a hand built engine

you know already what you have. Pullies probably are the best you can do.
Ok I missed that. And it makes a bit more sense now. I'll create a new post to get my questions answered for my application. Probably just do the basic mods and look to make a turbo setup a bit down the road.
 

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Discussion Starter #11
Sorry for the late response, no internet service for 2 weeks. I run a 178mm crank pulley compared to the 155mm stock. I also had the SC pulley changed from the 65mm SC pulley from Eurocharged to a 70mm(stock turned to that 70mm I wanted). A 178/70 combo takes me past that 15,000SC rpm a bit. Guys doing 178/65 have issues and that takes the SC way beyond it's range so than it pumps hot air.
Eurocharged.com for the pulley kits and tune. Near $1000. for the pulley kit. I run 550cc injectors, stock is 440. A wideband o2 sensor is needed to make adjustments as I use an AFR under12:1, shooting for an 11.5:1 for safety. My last mod was deleting the secondary cats, then using the Magnaflow tru internal x-pipe muffler there leading with 3" piping to the Borla out back, still loud to me and may add a perforated, 4-5" round muffler between the mag. and the Borla. Remember that only the Borla and Hooker mufflers do not drone though I only use the Borla as it has awesome quality. More if you like, Mark
 

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Sorry for the late response, no internet service for 2 weeks. I run a 178mm crank pulley compared to the 155mm stock. I also had the SC pulley changed from the 65mm SC pulley from Eurocharged to a 70mm(stock turned to that 70mm I wanted). A 178/70 combo takes me past that 15,000SC rpm a bit. Guys doing 178/65 have issues and that takes the SC way beyond it's range so than it pumps hot air.
Eurocharged.com for the pulley kits and tune. Near $1000. for the pulley kit. I run 550cc injectors, stock is 440. A wideband o2 sensor is needed to make adjustments as I use an AFR under12:1, shooting for an 11.5:1 for safety. My last mod was deleting the secondary cats, then using the Magnaflow tru internal x-pipe muffler there leading with 3" piping to the Borla out back, still loud to me and may add a perforated, 4-5" round muffler between the mag. and the Borla. Remember that only the Borla and Hooker mufflers do not drone though I only use the Borla as it has awesome quality. More if you like, Mark
Do you really need the larger injectors? I'd think the 440 would be fine. How much power are you making?
 

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Discussion Starter #13
The car needed the larger injectors. I tried the larger injectors. Also bought the fuel injector fuel that is adjustable, Rob(owner of the Needswings) sells it but it is costly. I only went with the fuel section which gives fuel adjustablity and the pressure/volume needed. Of course a wideband O2 sensor gauge is needed. I use the kit sold by PLX Devices. I run mine just a tad rich, 11.5-11.9:1.
Get the tune from Jerry at Eurocharged.com and Rob(owner) of needswings.com for the rest. Much of what Rob sells can be had elsewhere but Rob sells some unique combinations with all parts included in his correct, tested parts that make his kits simple for installation.
My complete parts modification:
1. Needswings CAI
2. Fuel pump for fuel adjustable kit with a regulator.
3. I stack pulleys to get the 20psi that I run.
4. Dual air inlets with the filters placed before the radiator9DCAI)
5. 550cc injectors(ebay)
6. New spark plugs and associated parts in that kit.
Really I have little mods for power and will not place them in this post. Feel free to contact me with any more questions. Sweet

I have not been nn a dyno with this car but will look into finding one, maybe in Sarasota. I shoot for an AFR between the numbers listed as I am running 20PSI at WOT. If any particular curves are important feel free to ask
 

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I am interested in your exhaust mod. How does it sound? Could you give me more detail on this mod? I would like to have a car with a deeper sound without a drone or a obnoxious sound. A guy in a new Porsche Boxster pulled into the gas station while I was fueling up and the sound from that car was just right. If you could direct me that would be great!
 

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Discussion Starter #15 (Edited)
I run 2 mufflers. TRU internal x-pie Magnaflow and a Borla out back. Still a bit loud for me and a 6 will not give a deep sound. I wanted to get the best power and mileage went up some also. From experience muffler tips with perforated internals help for a deeper sound.. I highly recommend the Magnaflow dual in/dual out to replace the rear cats. I also used the magnaflow "y" pipe on the back side to bring the 2 outlets to one 3. From that the 3" pipe runs directly to the Borla Pro XS, offset in and center out. To do again I would have the muffler sit back furthur so I could add a 3" perforated tip which helps for a deeper tone and does not hurt performance. Now I need to come up with something custom as most tips extend out too far. These cars are known for not gaining much power with exhaust work, even with headers.
 

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Discussion Starter #16
Do you really need the larger injectors? I'd think the 440 would be fine. How much power are you making?
I could not get the proper AFR with the 440cc injectors so I got the 550's for $200. Between the injectors and the exhaust I have a flawless idle. You will need a wideband O2 sensor and gauge, a MUST. I prefer the PLXDevices units, my 3rd, very accurate, good price on ebay. Remember I run 21psi and not the stock 14psi. I stack a 178 crank pulley and a 70mm SC pulley having tried the 65mm SC pulley from Eurocharged which is aluminum and prone to failure. There is a machine shop that turns the stock pulleys, probably safely to 67mm. Much beyond SC speeds of 15,000rpm are likely beyond it's efficiency range. Since I do not race mine....and do a lot of part throttle passing I am fine. Just ordered a pair of TOYO PROXES R888's which will STICK, no spin.
I estimate the power at 370 at the wheels, dyno soon.
 
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