41psi with vac off and 39 with vac on is a major problem. You should be around 32psi or so with the vac line hooked up. Unless of course you cam gives you literally no vacuum.
Oh, it can be done. Just not at 46 psi. At one time, I pushed mine upwards of 90 psi and supported a blown 302 to nearly 400 RW with 225L HP Walbro, and an FMU.
This was by no means ideal and things got considerably better when I swapped to 42 and kept pressure much closer to stock levels. The whole fuel curve improved.
41psi with vac off and 39 with vac on is a major problem. You should be around 32psi or so with the vac line hooked up. Unless of course you cam gives you literally no vacuum.
Ok guys this is what I did:
I re checked my fuel pressure numbers and this is what I got, vacuum OFF 39 psi vacuum on 34psi.
I have a 70mm MAF tube with sensor F2VF-12B579-AA AFH70 which I just installed and disconnected my battery to reset the ECM. Runs fine, the only problem is that I forgot my DMM to measure the voltage on that sensor to see if it makes any difference compared with the stock sensor.
I know it is kind of hard for you to tell me this but have to ask, are there any adjustments I have to do on the fuel pressure, or it will run fine @34 psi?
Eventually I want to go to 24 lb injectors and I’ve been reading about the best way to do it, if you can give me your opinion about this would be great... MAF/tube calibrated for 24 or performance chip??? I’ve heard that the first option is just cheating to the ECM and in my opinion it is kind of... Cheesy
I measured the voltage on this other MAF sensor with the 70mm tube and it gave me 1.16 - 1.18 Volts at idle, so I guess the stock sensor and 55mm tube is good..
I have a 70mm MAF tube with sensor F2VF-12B579-AA AFH70 which I just installed and disconnected my battery to reset the ECM. Runs fine, the only problem is that I forgot my DMM to measure the voltage on that sensor to see if it makes any difference compared with the stock sensor.