n75 j and 4 bar fpr

s3_kev

Stage2'd!!!!!!
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is this a good idea :idea: to do, replace the n75 valve for a n75j and replace the fpr with a 4 bar regulator then get a custom code re mapp? :confused:

if so what sort of power would i be looking at 270-280bhp :uhm:
 
People change the N75 to adjust the characteristics and level of boost without mapping. If you are planning a custom remap, then the you can specify all this via the software without the need to change the valve. Also the ECU may go into soft limp, due to the unexpected extra boost.

You only fit a 4bar fpr if its decided that the standard injectors can't supply enough fuel at high revs.
 
so basically you reckon id be better of just getting the custom code re-mapp? could i get it custom with out any other mods and specifiy what i want then rather then going for there generic mapp
 
Thats about the size of it.

If you want to specify a kick in the back at lower revs or smooth building torque, then you would need to go for a custom map.

A generic map will be very good. It will be what the tuner feels is the best all round setup.
 
ok i understand that but ive read that the n75j is good after some re mapps because it can raise boost pressure and prevent turbo surging which is my biggest problem with the s3 at the mo, would like to have more of a constant turbo pick up. if the n75j was fitted prior to the custom code would they not be able to mapp it into the software to stop the limp mode, plus the 4bar regulator is used in the revo stage 2 software so if i was to want more of an agressive setup seems this may be needed??? also been looking at the backdraft garret replacement turbo would i be better just getting that and the custom code then instead of wasting money on the fpr and n75???? cheers kev
 
If you are gonna go down the big turbo route soon mate I wouldn't bother with the remap now. It would be a waste of money as you will just have to pay for another remap after the turbo is fitted.
 
If you are gonna go down the big turbo route soon mate I wouldn't bother with the remap now. It would be a waste of money as you will just have to pay for another remap after the turbo is fitted.

im planning to do these mods prior to the re-mapp as im awere that to get the best out the re-mapp is to do the mods first thanks for the advise though, is the standard cat back exhaust section restrictive???
 
i have an AMD map and i fitted a n75j and it has improved the cars power a fair bit, it has raised the boost to about 1.6 bar and pulls very well to the red line. i have never had trouble with limp mode but i think its just a case of some cars will and some will not. ive run this set up for about 6 months, i also fitted a boost guage to keep an eye on it.
 
i have an AMD map and i fitted a n75j and it has improved the cars power a fair bit, it has raised the boost to about 1.6 bar and pulls very well to the red line. i have never had trouble with limp mode but i think its just a case of some cars will and some will not. ive run this set up for about 6 months, i also fitted a boost guage to keep an eye on it.
yeah i have the boost gauge at hte mo and see it ranging all over the place goes up to 14psi then drops down to 6psi and starts to pull up again and reaches around 10-11psi, how is it with the re-mapp and n75j???
 
The J valve may well be okay. As mentioned above its a lottery whether you hit limp or not.

Interesting point about the J valve and surging. I had surging issues and fitted an H valve. It did cure the prob, but I couldn't run the valve for long. I have no idea whether you could use the J valve in conjuction with a remap to sort surging. The resistance in these valves differs and they react faster or slower to ECU commands as a result.
Give some of the tuners a call on that one.
 
The N75J valve will raise the boost over a standard N75, the boost levels are however set at the remap and vary between different maps, imo you should just get the boost set where you want it when mapping the car, go for one of the more aggresive maps to start with mate. My Jabba map is set to peak at 1.6 bar anyway, if i fitted a J this would take this higher still and probably push the car into limp mode.
 
i have an AMD map and i fitted a n75j and it has improved the cars power a fair bit, it has raised the boost to about 1.6 bar and pulls very well to the red line. i have never had trouble with limp mode but i think its just a case of some cars will and some will not. ive run this set up for about 6 months, i also fitted a boost guage to keep an eye on it.
do you no what engine code you have??
 
not sure on the code, its gone out of my head and it dark and raining now. its 2001 facelift 210bhp.
 
not sure on the code, its gone out of my head and it dark and raining now. its 2001 facelift 210bhp.

think it might be the amk then, lol. think thats why yours is ok been reading on other forums and found out the earlier ecu's dont measure the boost pressure like the newer ecu's thats why some go into limp mode but your self and me should be ok
 

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