fuel pressure regulator help

[motrmaniac]

alright i instaled fpr have 680cc injectors with 255 walbro safc controller. my problem is it still runns pig rich at wot. when i turn the pressure down to 20 psi at idle and then attached hose it runs better. but set at 43.5 it runs like garbage... i tested for boost leaks and dident find any.. any ideas? this is on a 98 gsx

 

[fatherbubble]

run it at 43.5 an tune it the injectors are dumping too much fuel into it. More than what is needed to run your turbo.

 

[motrmaniac]

yea i went for a tune they tuned it best they could but said i needed fpr so i got one installed it .. i checked the values in the safc controller and up top alot of the values are -30 .. and im waiting for my new exhasut header to come before i bring it back to get tuned again but i want it to run just a little better

 

[ZiggysDSM]

yea i went for a tune they tuned it best they could but said i needed fpr so i got one installed it .. i checked the values in the safc controller and up top alot of the values are -30 .. and im waiting for my new exhasut header to come before i bring it back to get tuned again but i want it to run just a little better

you need your fuel pressure high or at least stock for wot so you dont run lean, use your afc to turn down your fuel and it will run alot better. if you have a logger check your o2 and get it to 14.7 at idle thats where you want to be

 

[anteversion]

you are supposed to be good enough but very border line with afc and this size of injector. The thing is that you will be too much in the negative range at wot and you will have huge knock and you don't want that. So, it can be a good solution to adjust fuel pressure slightly lower than the stock value. It will make the injectors act smaller and it will not make a huge difference in the spray. You can use this link as useful worksheet.
RC Fuel Injection