i looked around a bot for this and couldnt find anything so here it goes. i recently discovered i have a re flash, not sure what brand and it supposedly 20 psi. will get a boost gauge soon to be sure. but my question is, if i install a forge wastegate in. it says in its description it can increase boost about 2-3 psi, should i be worried about overboosting from that? and also if the wastegate is vacuum controlled, then how can a re-flash set you at 20 psi? thanks just trying to gather more info on how everything is running so i understand it better and get it as efficient as possible.

 

Is this the one you are referring to?
Audi B5 A4 FWD 1.8T > Engine > Turbo > Actuator > ES#1832381 VAG K03 Longitudinal 1.8T Adjustable Actuator - FMACVAG02

I haven't read about anyone using one, but may I ask why you want to? Unless your current wastegate isn't working I'd put that money elsewhere.

The wastegate on a stock or chipped car is vacuum/boost controlled via the N75 valve. It regulates pressure between the compressor housing and wastegate based on engine load and throttle position. So to answer your question, a flashed ECU will send a different duty cycle to the N75 that will allow the wastegate to stay closed longer to allow higher boost levels.

 

like said don't buy a aftermarket wastegate unless yours is fucked

spend your money on a boost controller or something usefull

 

It will hold boost a bit longer, but so will a cheap mbc.

 

Is there any upgrades to the n75 or that's done by ecu tuning

 

seerlah over on audizine was running the forge wastgate. there is the n75 race version, but i hear they are crap. better off running an mbc in line with the n75 if you want to control boost. or you could always run an mbc in place of the n75, but its not a popular option on a small turbo. as far as the k03 goes, 20 psi is about as good as it gets. it wont handle much more and pressure starts dropping off so fast. i know people really like making their cars fast for cheap, but the k03 can only put out so much power. sometimes people spend so much with exhaust, intercoolers, tunes and what not maxing out the k03 when they could just run an elim with tune and injectors for about 2200$ and it will make way more than a k03 will ever no matter how much exhaust and intercooler you put on

 

thats exactly what i wanted to know. ill prob get a boost guage first and eventually a controller, but i need brakes, and coilovers. but i was actually thinkin i would go with 315cc injectors before going anymore boost. i just wanna make sure the boost system is working well. i dont want any more that 20psi thats alot imo. will the stock fuel pump for ok with 315cc injectors? and should i get a new higher performance regulator with it? thanks for the anwers guys very informative
also i dont know if and of the "mdc?" was changed or the actuator or anything. doesnt look like it was, didnt tear it apart that far or look for it.... or know where it is for that matter lol

 

Do you plan to get a tune that can handle 315cc injectors? You can't just swap higher flowing injectors without a tune designed to use them.

 

u mean a new ecu set up? no i wasnt aware that i had to do that to use them. it makes sense though. i dont really want to further modify the comp more than it is. cause thats one less thing i dont neccesarily have to change. im not sure how many more engine mods i wanna change though. cause then i have to re set up everything or spend alot which is what it sounds like.

 

Dammn I should've read this earlier. I went ahead and bought the ecstuning racing n75 , ill let u kno how it is , if it is crap ill change it bak to stock n buy the mbc