more 4.3 q's

[35xj]

got a 99 vortec 4.3 in the buggy, got the fuel line adapters from jegs. Questions....


Which of the 2 top lines are which? Return, incoming fuel? Both mount side by side and go into the intake. One has a schraeder valve on it? One is a little bigger dia than the other? Which is which?

What is the 3rd hard line? It goes into the pass side of motor and has a schrader valve on it? Do i need it? Remnants of a tag say something about evap?

Its using a fuel cell and hard lines. thanks. dave

[BULLET99Z28]

The line with the schrader vavle is the inlet,thats where can mount at fuel psi gauge to check pressure. the evap line can be eliminated i believe. It can be tuned out of the pcm,so i won't throw a code or anything,plus it simplfies the fuel system. I know you can elimate the evap on a LS1 based motor,just have to have it tuned ou of the computer

[35xj]

Awesome. fuel inlet and return run side by side and evap can be blocked off physically?
thanks, can't wait to hear this thing fire!

[BULLET99Z28]

Evap should be just for vapors. Would have to look the vortec setup,but it shouldn't be that much different than the newer LS-based engines. the older vortec like yours should be OBDII emissions systems,which is what the newer stuff is. i eliminated the evap,egr,AIR,and rear O2's on my 99 Z28,all thru tuning on my laptop

[35xj]

the evap has a schreader on it as well. its hard line, similar size to fuel lins with a strange plastic end/hose on it. goes into upper rear driver side of motor, into some kind of sensor housing. Looks important, but i don't really know. thanks for the help. dave

[under_psi]

bumping an old thread to educate my non GM saavvy ass....this was the only thread that i found in search that was similar to what i needed.....

i have a 2000 model vortec 4.3 and was wondering if anyone could tell me the size fittings that i need to attach to the two lines @ the intake...? also, i am going to use steel braided hose, so what size hose will i need too? i have -8 fittings on the fuel cell.....

and, lastly, in the 2nd post, the line with the schroeder valve is referred to as the "inlet", uh, return line, right???

[Turtle Bite]

and, lastly, in the 2nd post, the line with the schroeder valve is referred to as the "inlet", uh, return line, right???

umm no, the inlet is coming from the fuel pump to INto the motor. The return line is the smaller tube of the two going back to the tank/ cell. I used AN6 line with my adapters, which is plenty big enough for 190hp. I believe the adapters are 21mm/19mm with the O-ring, but I would have to look. There are russel part #'s in one of the jeep forum TOTM engine swap threads.

[under_psi]

thanks.....

[under_psi]

umm no, the inlet is coming from the fuel pump to INto the motor. The return line is the smaller tube of the two going back to the tank/ cell. I used AN6 line with my adapters, which is plenty big enough for 190hp. I believe the adapters are 21mm/19mm with the O-ring, but I would have to look. There are russel part #'s in one of the jeep forum TOTM engine swap threads.

could not find the part #'s in any of those totm/totw threads.....unless i did not find the righ thread....

can anyone else confirm this fitting?

i am sorry for the rookie question, but have never dealt with this engine before and i am sure not getting any help here in town from the shops that carry these types of fittings, not to mention the chevy dealers...

i am going to take a pic....

for the record, i have -6 connectors off of the fuel cell and have the 3/8 or -6 steel braided line already....

brb with pic....

[dboy]

call summit racing and tell them which engine you have and they will tell you which adapters you need, thats what i did. 12 bucks and a few days and i had the ones i needed.

check out my build-up for my part numbers
http://www.binderbulletin.org/forums/showthread.php?t=72151

[under_psi]

thanks bro....

i am still gonna post teh pic, just b/c i have been fighting with the camera to load them onto the computer....

[under_psi]

thanks a MILLION for that...i just looked at that part....they are exactly what i need.....

:thumbsup: