So there was a chart made by another member here. I think the chart was sorted in a way that made it difficult to find information and not all combinations were present.
I tried my best to extrapolate the information on known values and include every pulley combination that I could find available for sale. (The values have not been officially tested in any way, but should moreso serve as a reference guide. Anyone with more knowledge, please feel free to critique)

 

Thanks!!

 

I'm running a 154 / 72 Combo and what your chart shows is exactly what I see in 4th on a 60F day. My car has always seen higher boost in 4th than in 3rd (1psi difference), more in 3rd than 2nd etc. I am running long tubes as well. On a sub 40F day, i get as much as 16 in 4th with the colder, denser air. Moral is, its better to track the increase on your specific car than the absolute indicated boost level and keeping in mind the other environmental variables.

 

HEY EVO !!

So what is the general consensus on optimal boost on for the e55 ? I did the 172mm pulley ages ago and am curious if opinions have changed since then. It used to be that folks would run ~190mm crank pulleys (IIRC) for huge torque, but marginal HP gains (over the 172). Furthermore, the IATs went through the roof after a few runs.

In essence I am wondering if I should change my SC pulley? (Live in Cali with wonderful 91octane.)

 

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what cooling mods do you have? If I were you I would add the 83 clutched pulley and you will be right on the money. I would have 550cc injectors with it for sure though.