View Full Version : N75 Valves?
BeezerDiesel
10-03-2005, 13:57
Okay I've done a quick search and there are so many posts with N75 valves in; it would take all week to sift through them, so -
Does anybody have the definative answer to which N75 valve suits what state of engine tune (or even what engine each N75 version was fitted to originally, to give a bit of a guide)? Petrol and Diesel.
Are there any other VAG websites that have a guide or useful info on their fitments or better still, as many of you spend an unhealthy amount of time and money visiting tuners and rolling roads, what are your/their experiences and recommendations?
My 1.8 20vT came as standard with an F N75. The boost was progressive and smooth.
I changed to a J N75 and found it more aggressive, more initial kick low down due to more boost, and more boost across the range generally.
No figures to back it all up though.
Blucupra
10-03-2005, 17:45
My 1.8 20vT came as standard with an F N75. The boost was progressive and smooth.
I changed to a J N75 and found it more aggressive, more initial kick low down due to more boost, and more boost across the range generally.
No figures to back it all up though.
I thought that the standard N75 valve was an C model. I tried an J valve but my car surges and hesitates. I am back to stock now
Jeffrey
Andy
The TDI engines standard N75 works fine, the 1.8Ts you can tweek by fitting different spec N75s to change the boost but ive not read anywhere of people changing the TDI one, i beleive the standard one does the maximum for it at the moment.
mine came with a F, changed it to a J and there was a big surge and an increase across the range but it wasn't smooth - surging all the time and got worse, so i changed back to the F. Read on here that it works well with chiped cars.
Cheers
Danny
BeezerDiesel
11-03-2005, 04:35
Excellent so far, be nice to have a definative guide to what valve is best with what state of tune (with the exception of Diesels when it's just nice when they work properly eh Stew?)
They seem to react differently to every car. You just need to experiment and find one you like.
Just put a "J" on my remapped Ibiza after 2nd standard one went phut so far so good although only driven it home from work tonight (13 miles) so a bit to early to really tell.
I ran a J on an upsolute coded LC for 2 years with no problems whatsoever.
IE limp
I spent a couple of nights wading through various threads on 20vturbo.com and the like and general concensus was that the J provided the smoothness of the F with the aggressive delivery of the H (without limp mode)
For info my boost gauge would hit 1.3-1.4 bar
The car was much quicker with the J and this became very apparent when I put the stock valve back on before I flogged it.
Its a very good modification for a re mapped car