what is good fuel pressure???
under load im getting like 16-18
is this normal??
what is normal??

39psi with 0 vac is stock.. I run 43PSI on 0 vac

16 - 18 PSI of fuel pressure? ouch. You sure you're not looking at a vacuum gauge?

i have mine set to 50psi. 16psi is way too low

43psi. for me.

what would be good fuel pressure on a slightly modded block

Hooked up a snap on fuel guage to the valve on the fuel rail...
i set it at 42 with the vacuam off when i plugged the vac back up it went down to 35.
at idle it will hold at 35 but when you give it gas it jumps down to 16-18 pounds
someone else on here said it was suppose to go up when you give it gas???
I have the stock pump 36 pound injectors think im sucking the pressure dry
just giv9ing it gas not flogging it???
i have a 255bbk pump and a new fuel filter redy to go in.....if it ever stops raining...

what mods do you have...... 36# injectors...

90m maf 36#injectors edelbrock upperlower 75mm throttle body
shorty headers 4.99 5.11 lift cam cai kirban adj fuel reg.gt40p heads

the stock pump is definitly your problem... Is your car actually TT?