Looking at my '01 225Q, I see the N75 is made by Eaton (EM-3), with a six or seven number ending in "F". Does anyone know if that is the OEM valve?

Also, is the "J" version of the N75 the same as the "Race valve"? What's the difference between the C and the J?

 

From what i've read the "H" valve is the race valve. A "J" valve is supposed to be more subtle in changes giving you boost earlier, but not being so sharp with the application. I've read that "H" valves are hit and miss inside people's cars. Most people are happy with the "J", but again this only from what I read around the various forums.

One thing I noticed last night while messing around on the vag-com is that I came around to a measuring block that showed duty cycle time on the n75 valve. Mine was at 0% meaning it needed to be changed. My 225Q has 65k on it. I will change mine out with a "J" as soon as I get the money.

 

Do you know of other J venders in addition to?

http://www.autotech.com/prod_engine_fuelrl.htm

 

n75 = no adjustments = waste imho

 

if you take your n75 out and put in a MBC instead, and you have a CHIP, would it throw a CEL ? or the chip already knows you're gonna take that piece of crap out?

 

The chip just raises the requested boost up and adjust the fuel and timing maps for it. If you run equal or more psi than what the chip is written for, you fine. Running less with throw a cel since it thinks you have a pressure leak

 

nice to know..thank you.