So I recently bought a 84 720 4x4 with the stock Hitachi on it's last legs, thinking "gee, I've got a couple 32/36 DGVs lying around; I'll just convert it. How hard could it be?"... I'm really starting to regret that...

Initially I ran into issues with the adapter (I was sent a L20 adapter instead of a Z24 adapter by Pierce Manifolds) and not getting a good seal on the manifold. Turns out I had a crack on one of the runners and had to replace the mani. A lot more effort than I expected for what should have been simple (end rant)

At this point, I've got everything together, no significant vacuum leaks, and the wiring right, but I can only get it to catch for about 5-10 seconds and it starves. It seems like it is draining the bowl, and if I let it sit for a bit to refill it will catch again for 5-10 seconds (electric pump). I'm guessing low fuel pressue, but does a 32/36 DGEV really want a significantly different pressue than the stock Hitachi? It still ran when I swapped the Hitachi back on the make sure the issue was carb related.

ive got a 86 720, when i got it, it had the TBI set up, i got a manifold from an 85 z24, blocked off all the vac lines, blocked off the egr, and picked up a universal in-line electric fuel pump, i discoverd that you also need an in-line fuel pressure regulator( 25 bucks at auto zone) ive got a 36/36 synchro weber and mine like about 4psi it runs like a champ

the weber will also use more fuel... the in-line regulator is a great idea but also maybe a pump that flows more?

im not sure what his stock pump was rated at, but, the pump on mine was running something like 15psi, and it would have turned my carb into a sprinkler. the one i picked up was rated at 4-7 and before i put on the regulator it ran really rough, and would stuble and die, so im thinking it was gettin to much fuel. so im guessing his problem was he's gettin too much or not enough

Yep, it was the pump (pushing to little fuel). When I got a gauge inline on the fuel feed it was pretty obvious it was fuel starving once it got going; it could pump enough to slowly fill the bowl, but not enough to keep the engine running. New pump and it's all happy now.
Modified by mdjett at 11:01 AM 12/17/2009

Anyone know what the PSI should be for the stock carb? My pump died over the summer and I got a generic one from Pep Boys. Truck guzzles fuel like crazy and I'm wondering if the pump may be part of my problem.

i'll check my manual to see if it says anything.... but you can't be too far off with a generic really.... anything less than 4.5 should be fine.... and then with webers its recommended to run 3.5 with a regulator.... so 3.5ish should be ok but i'll double check to see if it says anything