which diverter valve do i get

[turboaudi]

i want a newer , better one than the standard one on my 96 18 turbo , anyone got any suggetions/links to any . thanks in advance

 

[Beerzo]

tbh they are much of a muchness dont go for the obvious cheapo ones. Stay away from atmospheric ones and you shoud be cool. FORGE or BAILEYS are the most talked about on here. Forge would get my nod.

 

[Rich]

What about the N75J from the TT? How do the forge ones compare? I will probably be changing my standard one soon too ;P

 

[DavidR]

i want a newer , better one than the standard one on my 96 18 turbo , anyone got any suggetions/links to any . thanks in advance

Buy a new Bosch one. It will be newer than OEM and (if a newer version) stronger.

The aftermarket ones offer no improvement in power, reaction time or anything else unless you are running upwards of 1.5bar of boost.

I had 3 different ones on my A3 1.8T... Forge, Bailey and some other one - they all increased throttle lag and reduced responses.

Bling - yes
Performance - No, no, no...

 

[turboaudi]

so what about the hyperboost diverter valves on the amd website, they claim to reduce lag and make throttle response better, is the n75j valve an alternative for the dv or do you use both

 

[DavidR]

They are misleading claims.

The internal volume is greater and the relatively heavier piston moves more slowly than the OEM diaphagm... Waste of money IMO

The N75 Valve is not a DV at all, but the valve that controls the wastgate on the turbo. It receives a pressure signal from the boost side of the engine, feeds a signal to the ECU which controls wastegate opening.

 

[Rich]

So the N75 dosnt replace the standard DV? I was under the impression it did? :S

 

[DavidR]

Nope.
Completely different...

 

[turboaudi]

so to cut a long story short , you are saying to buy the newer genuine audi diverter valve and also add an n75j valve,, will this make considerable differences to throttle and lag, ie better responsivness

 

[Rich]

Aaaaah ok, but it still is worth changing your stock N75 for the one from the 225 TT? A lot of people seem to recomend it? And as for the actual DV its best to just refresh the standard one after a while?

 

[DavidR]

so to cut a long story short , you are saying to buy the newer genuine audi diverter valve and also add an n75j valve,, will this make considerable differences to throttle and lag, ie better responsivness

Nope.

An updated Bosch (OEM) DV will be less likely to tear than an older one, especially on a chipped car. You'll notice no difference to drive unless your OEM one is busted.

The N75J valve mod is a completely separate issue discussed widely on this forum. It can cause ECU limp mode as a side effect of increasing boost.

 

[turboaudi]

i think mine must be busted then , the car seems to hold back on boost on some occasions ,i replaced the maff through others advice but it didnt seem to make much difference, is there any distinguishable things that would point obviously to that being at fault

 

[DavidR]

Al B had a similar issue with his S3 - I don't think he ever got to the bottom of it.

I found that both the A3 1.8T and S3 would occasionally (i.e. less than once per drive) hold back on boost for a moment or two. Usually when going on / off the throttle quickly. I think it may be normal.

To check the DV remove it and see if you can blow air between the 2 larger pipes - if you can then it's broken.

 

[DavidR]

And as for the actual DV its best to just refresh the standard one after a while?

See above post for how to check them. The newer ones (can't remember the latest code) are more robust. They do all tend to be prone to failure with time, especially if the boost is non standard.

I always carried a spare.

 

[Rich]

Right ok, so while the forge/baily DV's may not offer any performance gains, in fact they can reduce responsiveness/increase lag but they might be stronger wearing so if one was to up the boost and didnt want the hassel of having to replace the bosch DV every xxx miles when it went pop they might be a good choice?

Regarding the N75J Valve I think it might be good to collect some facts as to exactly how you can use this valve without worrying about your ECU going into limp mode. it looks like a lot of people seem to be pulling it off with no problems and getting a fair gain from it.

 

[Beerzo]

Get an N75j valve that will not cause any problems whatsoever. Its when people start fitting the larey ones like the N75H valve (I think its H) is when people run into problems. Stay away from the expensive "Race Valves" as these are usually the larey on and a genuine VAG part with the part number rubbed off. So they can charge you more for something that should cost in the region of £40.

 

[PhilR]

Go for the bosch 710N diverter valve off the 225 TT, only cost about £20 or so as opposed to the 100 plus for forge or bailey, If you are remapped you can install it the other way round than standard this apparently helps the life of the diapragm as it stops pressure from the vacuum hose and boost hose fighting against each other.

The N75J valve is the boost control valve off an s2 not a tt

 

[Rich]

Cheers guys, that clears it up a lot. I'll whack on a 710 when i get my remap then and try the N75J a while after that to make sure it has no negative side effects. I think I was getting the two confused before now

 

[PhilR]

You are best off changing your diverter valve before a remap, as chances are your std one will be dead if its never been changed. That way you can souce one from the cheapest supplier and fit it yourself rather than paying the tuner for the valve and labour.
Remember its a 710N you want for a remap, model numbers if i recall correctly are all the same bar the suffix i

 

[Beerzo]

Anyone got the part number for the 710N

 

[Beerzo]

Its cool got it from VAG Parts