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Drivetrain loss and increase in boost from the Renntech pulley kit for a 32...

869 views 1 reply 0 participants last post by  Arnee 
G
#1 ·
I asked Renntech 2 questions that I have been wondering about for a while.<br> <br> 1. What is the drivetrain loss on an SLK?<br> Answer, typically for MB it is 17 to 20%. They measured it on a C coupe and it was 19%. With a shorter driveshaft, the best guess for an SLK is 18%. Therefore, my revised hp/tq estimates for my 32 after then ECU and pulley kit are: stock tested at 304/290, +40/+56 from Renntech ECU and pulley kit for a total of 344/346 at the wheels. At an 18% drivetrain loss, new estimate is 405/408 at the crank.<br> <br> 2. What is the boost increase from the pulley kit?<br> Answer: +2 psi. They measure 12 psi before the pulley and 14 after the pulley. Periokid, you'll likely see 1 full bar if you get the pulley kit on your boost gauge.
 
G
#2 ·
I'd believe that.

Although it's totally different, when I had the pulley for my SLK230, it showed an increase of 45hp at the crank from going 6psi to 9psi.<br> <br> Before numbers are:<br> 155hp at the wheels, 185hp crank (spec)<br> <br> After:<br> 201hp at the wheels, 233hp crank (adjusted as per 16% drivetrain loss)<br> <br> This included the pulley and intercooler upgrade. With the GIAC chip, the power increased at the wheels from 201hp to 212hp, not much additional.<br> <br> <br> <br>
 
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