I tried doing a search but had no luck. I have a 03 coupe that im in the process of putting a turbonetics kit on and I was wondering how does the fuel pressure know to raise with boost when theres no reference for it , I will be using a Utec with it , any help would be great thanks, John

 

you dont have a return fuel system, so you cannot regulate pressure anyhow.

thats why people go with big injectors to compensate

 

Base fuel pressure goes up with fuel pump assembly mod. As you boost, FP will decrease. The injectors and fuel pump half a$$ compansate for it, I put a RFS on very shortly after the TN install the car never ran good on the reflash.

 

So do I need a FMU doe's that controll fuel pressure or you guys trying to tell me that theres no way for me to controll the fuel pressure. Sorry to sound like a newbie im just not used to working on these type of cars im more used to fords and chevy with power adders . I allready have a race car so im not whanting to go to crazy on building this car trying to keep it simple for know around 400 hp Thanks for the help

 

Simple = install the kit. Leave everything else stock, dont even add an exhaust and hope it works out lol...

 

^^ But no exhaust is no fun.

 

It's hard to believe that this is how it works I dont doubt you its just hard to believe you can get away with this without blowing something up. So what does the FMU do or is this for only a aux pump. I have Borla headers on the car that I made the kit fit along with a custom exhaust I better look in to this a little more, that's why im asking.

 

There is no FMU. The fuel is supplied by the 380cc injectors, mod'd canister and Walbro pump. When you add mods it tends to run the reflash deisigned for an otherise stock car lean. And thats where you get into tuning, fuel systems, etc.

 

hmm.. another boosted car in CT ... writes in his notepad

 

The answer to your question of how the car knows to add more fuel for the boost is in the modified air/fuel/spark mapping with the reflash. No your fuel pressure will not increase but the reflashed maps in the ECU will compensate forthe additional air much the same way the car did stock. It reads the increased air via the MAF and compensates with additional fuel based on the revised mapping in the ECU flash you get with the kit. If you are going to use a UTEC instead then you will be adding additional fueling via that however your fuel pressure will still not increase for boost. All that being said I run 53-55 PSI of fuel pressure static and never see below 48 PSI of fuel pressure under full boost. Car has never run lean even with a MD 5/16" spacer and Apexi WS2 exhaust.

 

These systems run a static pressure so you cant have a rising rate set-up unless you go to a return style fuel system.

 

So let me get this straight my tuner will have to compensate with the Utec to make this work right. I read that some people's fuel pressure are as high as 70psi does this make the car run alot richer, just trying to figure this all out. I will be using a walbro with the turbonetics modafications done to the pickup so will I see that much pressure or will be in the 55 psi range ?

thanks for the replys

 

The only way your fuel pressure would be in the 70s is if you didn't install the kit properlly. Your tuner should have no issues tuning this car.

 

Thanks, Miaplaya