Hey all, just picked up my TT last week and I absolutely love it...Its an 2002 quattro 225....but naturally i cant leave it be stock. I have already got an intake, boost gauge, and manual boost controller... with a forge dv to come soon. I am hopefully going to get a chiphere in a couple months but i have a few questions.....I am installing the mbc and boost gauge this weekend and was wondering....1.) what is stock boost on the 225, i have heard ~14 psi but just curious.....2.) what can i turn it up to before the ecu gets mad and goes limp mode on me....i know the diode mod can fix this but i would rather just wait for the chip....just wondering what the stock ecu will accept for boost so i can adjust acordingly.

 

The FAQ doesn't lie! 14psi is 225's stock boost. If you go above it you WILL hit limp. Just get a diode, it's like $1 and not hard to install if you can solder.

 

and if you want to go big turbo later id hold off on the chip because youll need to get a new program with a big turbo anyway

 

Its there for a reason. All basic stuff is covered in there, more advanced stuff in the BT and HP

 

I thought the diode mod is basically only for the TT 180 not the TT225 but perhaps they came out with the proper diode for the 225? I am sure Cincy
will chim in on that one. I don't think that you can turn up the boost much without a chip or diode mod without hitting limp mode. I think besides a
Boost Gauge the Chip/Tune should be the first mod for the TT 225. Unless you have the cash and can shell it out for a Big Turbo kit. I am pretty satisfied
with the way my car runs now and I for one am not going to be power hungry for more than I can afford Also, don't just think power but also handeling.
For me it was much more enjoyable to install a Koni FSD/Eibach pro kit and Neuspeed rear sway bar. The handeling has improved 100 % and the car runs
like a dream. Modding the car is fun but can get expensive. Just know where your limitations are especially when it concerns your wallet [8D]

 

4.3v Diode works with both. If you run a mbc w/o the n75, you wont have any troubles. If you keep it inline, you will need a mbc on the 180 to turn up the boost and keep the boost from continuing to rise on a 225.

 

alright...well i apreciate the input from everyone, and i have read the FAQ many times trust me... and i just didnt remember it saying anything about when you hit limp mode stock. So i guess my MBC wont be much good till i either get a chip or solder in a diode. I really do plan to get a chip in a couple monthsbut would like to try the diode untill thenbut i am a little hesitant. The diode and the 225 seem like not as good of a match as the 180. So a 4.3v diode will work properly? i would just need the MBC to keep the boost from going crazy? Another question is once i get a chip and the chip turns the boost up ...will i then be able to turn the boost up to some more to anextent without hitting limp? im sorry for all the questions guys....just trying to be as informed as possible...also is there any major differences between different chips?...all the ones i have seen seem really similar (apr, giac, etc)... is one the best choice based on power per dollar?

 

The diode mod works fine with a 225, it has been done several times. Yes, you need a mbc to set the boost with it.

A chip eliminates the limp mode and you can then set theboost to 20-24psi and dont forget to pull the diode before you chip it. All the chips are close enough to each other when it comes to performance, but if you plan on ever going with a larger turbo in the future, unitronics would be the best to go with. If your not sure, you can get revo and if you dont want to swap, arp or giac.

 

alright thanks alot...think im gonna have to give the diode mod a try since it only costs a few bucks till i get a chip