gsxr1216

so i got a new holley 4150 (80443) carb to to run on my new rebuild, 454 MAG and i have a few questions on how to plumb it all correctly if anyone has done this so i dont have to do it twice!!

first, the "vent/overflow" line from the mechanical fuel pump that used to go to throat area on the OEM quadrajet, where do i plumb that on the new holley, i have 3 spots i see, only 2 look viable??

pic 1 shows a "T" fitting that i can hook to easily but some of that goes into the choke so that doesnt look ideal??

pic 2 shows a hose barb into the linkage side of the carb throat area that looks like it will work but would require routing that hose around to the other side of the motor from its current side which isnt really ideal.

pic 3 is what appears to be a vaccum plug in the rear bottom of the carb, again this doesnt look like where i want to run the fuel pump hose but I'm wondering what this port is for and if it should be left like this or closed off in another way if it wont be used in my application.

thanks!

kubelwagonman

goes on the barbed fitting in second pic

firehawkcat

Pic #3 looks like a vaccum

tinman565

Just curious...how did you decide on that carb ?

gsxr1216

rmbuilder

tinman565

Is that a basically stock 454....or did you guys "warm" it up ? I can see the Edelbrock intake. Bigger cam ? Better heads ? Modified stock heads ?

gsxr1216

all stock rect port heads, for sure a lot bigger cam, about .620/.630 lift, all roller valve train now also. the new pushrods just showed up last night.

if i can ever get all these small issues sorted out it might actually make it on the dyno late next week to tune it.....

i have to fab a new fuel line now as the OEM doesnt line up, and run new vent hose for the pump since the old one wont reach the other side of the carb... and i will need to get a new throttle bracket to work with all oif this apparently...

my oil "primer" shaft that has a bushing on it so it will supposedly fill both lifter galleys doesnt seal for sh!t you can see the oil pouring out around it back by the cam distributor gear so i havent been able to build hardy any oil pressure in my valve train yet....

the new cam has metric threads so i cant reuse my old cam gear bolts.... so after calling about every local bolt supplier looking for flange head metric bolts and striking out i finally had to break down and order them from out of town. so for now i got cheap bolts from home depot in there so i could time the engine and assemble the valve train.. man all these little issues are just killing me from finishing this project...

i might actually see water by 4th of July if the stars align just right....

KWright

The hose coming from your fuel pump is for saftey in case your pump diaphram leaks it will pull leaking gas to carb. It should be plumbed to top side of venturies.if you dont have a place to hook on to carb a small tube epoxied into flame arrester will work just fine. All other unused vac. ports should be pluged