i hope someone can help me here....i just pulled the vortecs off my motor due to a vibration problem that just developed. # 8 cylinder has the exhaust valve burnt and thats what was causing the vibration at 1800 and up on the rpms. this thing wont run rich no matter what ive tried. its got a 52mm tb installed and 24 # injectors. i installed a auto meter air/fuel gauge and it shows lean almost throughout the rpm range except under full throttle. im lucky it was a valve instead of a piston. the heads are heating up faster than the motor and it results in the head temperature going to 245* because of the lean condition/combustion temps while the rest of the motor stays at 180* during initial startup/warmup..........anybody.....all suggestions welcome.....thanks

 

It may be the fuel pressure.....Your pump could be going out, not sure. Are 24lb injectors big enough for your setup? Fuel pressure set high enough?? Can't really think of anything else...good luck

 

i cant get my fuel pressure above 40 #s with the holley afpr. could my fuel pump be at fault? this motor has only 1300 miles on it and i dont wanna burn or crack a piston from it running lean....my header temps are running around 500* to 600*. but everyone seems to think thats about normal......anybody?

 

Pinch the return line off and see of the pressure goes up. If so, it's probably not the pump, but the regulator.

 

Dont forget that the O2 doesnt tell you wheather you are rich or lean. Just how much O2 is in the exhaust. If you have misfires, for whatever reason, your O2 will read lean when you might actually have a rich misfire condition.

As far as your fuel pressure not going over 40 psi that is a definate problem. What size fuel line did you run? To big and your pump may have trouble getting the pressure up.

 

the fuel pump/lines are factory. i cant try to pinch off the return lines because ive got the heads off the car. if i turn the adjuster on the afpr past 40#s the needle bounces very eratically and you cant tell where the pressure is at. after i get my new heads on ill install a new walbro pump. maybe that will do it. i dont know what else to do.....

 

does anybody know who carries the 255/walbro in tank pump?

 

http://www.neweraperformanceparts.co...15&NID=1429134
That was one of the cheapest places I have found. They shipped mine PDQ too.

 

http://www.autoperformanceengineering.com/

Get some gas in that thing before you break it.

You also might want to datalog the ALDL stream so you can get a real good idea of what the computer is seeing.

 

thanks guys, ive been trying to find this pump for quite some time now. i just hope it cures my lean condition......:hail: