I recently installed a 227/233 xe cam. What fuel pressure should I use with the stock injectors. On stock cars, I know that you lean the fp out to about 38-39, but I figure now, it needs to be more than stock

 

The right way to do it would be to leave the pressure stock(and the regulator) and get pcm tuning to get the whole fuel curve and timing right. You are looking to push the stock injectors awefully far though, contact a tuner or your tuner and get a tune setup for a pressure they recommend and set it to that pressure which will be a bit higher than stock in order to make injectors that are too small work. You can not properly tune a car without pcm work, you can apply a bunch of bandaid fixes and waste a lot of money trying.