LQ4 into a 3rd Gen/1972 Nova by frojoe

4 minute(s) of a 891 minute read

Nice! I dig that. With my tank, the recess I put into the top of it for the access panel area is the minimum height needed to the 90* bulkhead fittings on the top of the panel, in order to maximize the height in the tank under the access panel. That being said, there's still only enough height to just barely fit in a pump with its intake sock below and the output hose on the barb on the top of the pump with the minimum bend radius on the hosebefore it kinks.

Then again, I could lay the twin hi-pressure pumps on their side thus raising the intake socks up from the very bottom to maybe 1" above since they'll be guaranteed to be submersed in fuel, and the transfer pump can be on its side as well because air intake isn't such a big deal. But in the end, I really don't want to modify the welded setup in the gas tank.

Since it would be a direct drop in, I could add a hi-pressure pump in the existing mounting bracket and used that as the transfer pump. Then move the existing TRE 300 pumps to the new surge tank. Not a single thing, including wiring, would need to change for the main gas tank. The kicker is I still have my original Aeromotive Stealth 340 pump which wasn't actually the problem when "my fuel pump died" the first time, it was the wiring and tank bulkhead that failed.. so that could literally just drop in and be good to go.

From my research, it seems a hi-pressure pump with the same body as the Walbro 255 will flow just fine in low pressure applications. I was worried that continual low pressure would mean continual high gear RPM and maybe premature wear, but then the load just be very minimal so maybe it'll all be okay in the end? Also the low load of a single pump would mean much less heat input into the main tank, so that tank would be cooler than the surge tank and possibly help keep the surge tank cooler.

Something along these lines. I'm thinking it's best to return the fuel from the rails/FPR to the surge tank so that the discrepancy in fuel flow rates between the low pressure and high pressure pumps doesn't drain the surge tank into the main gas tank under low load aka minimal injector duty cycle.

1-18-2017

Clint.. haha gotcha. I'm a big culprit of over-thinking something to death from multiple angles, and then every once and a while Mark will slide in and point out yet another viewpoint that it pretty obvious but that I never considered somehow.

408GT.. you raise a good point, but you must not know me well.. I like making stuff haha. I'd want a cylindrical surge tank since it's the best for flow when combined with inlets & outlets that are tangent.. it's going to have a good amount of fuel flowing into and out of it thru multiple fittings, I'd rather make the flow as least turbulent as possible. I'd also want to maximize space, and with the design of dual pumps + brackets holding them + a nice sturdy bolt-on top lid for access with a good Viton seal.. all signs point to me just making one.