A4 1.8 T 150BHP IS IT WORTH FITTING A N75 J ?

[AUDI@WRC]

hello i have been reading up on these N75 J reg valves on these forums but all the cars have remaps would i see a difference fitted to a standard 1.8 t 150bhp ?

 

[docurley]

Have a look over on the tuning section there is a thread on there that covers this and yes none chiped car will see gains as reported by some.

 

[Beerzo]

I made 166 bhp on rollers with a tank of optimax and a n75J valve. I have the graph if you wanna see it.

 

[turboaudi]

what are they

 

[AUDI@WRC]

there are a boost reg valve but the n75 j is for a audi TT 225 SO IT SHOULD GIVE YOU MORE BOOST ABOUT 3-4 PSI ACCORDING TO forum members.

beerzoo does the car have more torque ?

 

[Beerzo]

Dunno what standard torque is but here is the graph....

1st Run
http://homepage.ntlworld.com/frazer.beer/a4rrgraph1.jpg

2nd Run
http://homepage.ntlworld.com/frazer.beer/a4rrgraph2.jpg

 

[mwarrey]

I made 166 bhp on rollers with a tank of optimax and a n75J valve. I have the graph if you wanna see it.

Is your car standard (apart frotm the n75j) ?. What year is it ?

 

[Beerzo]

Drilled airbox that all but that wont give more power i wouldnt think. 1997.

 

[Lowlife]

Thats a pretty reasonable gain for such a small cost. Is it easy to fit? Do you have a pic so I know where I'm looking for it, I'm new to the world of Audi!

 

[macattax]

Ok I am a bit confused by this.
Can somebody confirm is this valve fitted inside the airbox or is that the charcol solenoid?

 

[Beerzo]

Its fitted right next to where the dump valve is. No its not inside the airbox.

Piece of pi$$ to fit. But buy some jubliee clips or similar as i had to break the other clips off to get the old N75 valve off.

 

[Rich]

Anyone got a good link to buy these from? For some reason I can only find US sites :/

 

[Beerzo]

vag parts sell them

 

[PhilR]

I have an N75J my boot (its been there for ages) gonna try it once i fit my boostgauge, do you have dyno figures before and after the valve Beerzo ?

I have heard that 150bhp is a conservative estimate and the 1.8t normally has a few extra when standard

for example mine made 136 bhp on the rollers and was making no boost because the wastegate was knackered and wide open,

 

[Beerzo]

Nah dont have a before graph. The guy that done it on the rollers is a big VW fan and knows them inside out. So will know the engine well. After the first run he said that was good and strong is it standard i said no told him what it had and he was still very impressed at the pull and power it made. So i am assuing to a trained professional they can tell the difference they make.

 

[PhilR]

Cool I have heard good things about them I will be trying it out this weekend probably, like i say been wanting to fit a boost gauge before i mess about with it, dont want to be going limp !!

 

[billybravo]

ive took my n75 right out of the boost line but left it plugged in to the ecu and TIP as to not get any codes.

i now run a MBC which i think is alot better than a std or j valve as i have full control over my boost

 

[Beerzo]

billy bravo do you not get any errors at all from th n75 valve? Ie along the lines of it not doing its job?

How hard are the MBC's to fit? Do you or did you get errors thrown back.

What boost to you set the MBC at?

I see that you have your car re-mapped, what are the advantages of running a manual boost controller after having this done. Does chipping the car not put the turbo close to its boost limit?

 

[billybravo]

hiya no i dont get any errors on vag-com because the ecu thinks the vavle is still working

i went this way because ive tried the j and the std valve and yes i was impressed at first with the jn75 but after a while the boost went back to what it used to be as if the ecu found out i was trying to up the boost.

so i thought what the hell and stuck the MBC in now i see a good spike above a bar at the stary and a good hold at a bar along the range the car feels like a ******* monster now. I was running rich anyway from the logs i did on vag-com so im not doing any harm to the engine just getting a little bit more power

 

[Beerzo]

Yeah lamda probes should sort the fueling anyways.

But are you turning the boost up further than it was after you chipped it.

How did you connect the piping for the N75 valve after you removed it? Just a t-piece conector?

Did the car not work with the MBC when the N75 valve was connected?

Sorry for all the questions here just might be interested in doing this if its reliable enough. Where did you get the MBC from?

 

[billybravo]

ok at first i ran the MBC with the N75 inline so it went pressure outlet from turbo - MBC then to the N75 using T pieces looping over the to the wastegate side of the N75 eg the N75 was in the middle of the loop with the MBC conected on both sides.

but now i just run a line from turbo to mbc then to wastegate

but the N75 is still in the TIP with both of the other outlets blocked off and with the wires still contected.

im not saying this is a good idea for everyone but i like the feel of the car now so much more its like having a big turbo on there

 

[AUDI@WRC]

just fitted the n75 j valve but the long hosetail is on the opposite side of the valve compared to the old N75 ? does it make a difference if i put the long hosetail in the small hose or does still need to go in the big intake hose ?

gav

 

[PhilR]

just fitted the n75 j valve but the long hosetail is on the opposite side of the valve compared to the old N75 ? does it make a difference if i put the long hosetail in the small hose or does still need to go in the big intake hose ?

gav

you have to fit it in reverse of the original c (?) valve

 

[AUDI@WRC]

i have fitted it the same as the old one, but the long hosetail is not in the intake hose now its in the small hose.

 

[PhilR]

Just looking for a tech article, i have fitted one to a MK$ golf before and the difference in fitting was obvious but i cant remember what the difference was !

edit
should be busy at work haha and cant find the tech article i was looking for but this article explains the hose connectors

http://forums.audiworld.com/s4/msgs/1046677.phtml

ill keep looking ;-)

 

[billybravo]

you need the long one in the TIP and the n75 j should face the op side than the old n75

 

[AUDI@WRC]

how do you get the cable to reach the connector its not long enough ?

 

[PhilR]

can you not re-route the cable to gain a bit of length ?

 

[billybravo]

like said above you can aways make them a little longer i didnt when i ran one but the cable got pulled tight which porb isnt a good idea best bet is to just make the wires a little longer