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408GT do you have a build thread that I can click thru out of interest?
I started a build thread in the forced induction section, but there wasn't much interest so I haven't kept it current.
With having the return from the fpr, you need to make sure that it returns below the fluid level so it doesn't aerate the surge tank. The surge tank should hold enough fuel during a pass that the low pressure pump would have a head start on the larger pump(s). I have seen the return from the fpr plumbed both ways online (one way to the surge tank, and one way to the main tank).
My LTD was setup from the factory with a two pump system. A low pressure in-tank and high pressure one external on the frame rail. I actually have a brand new low pressure one in my tool box. I didn't use it because I don't think it's compatible with E-85. I should have just tried the low pressure pump one time just to see if it made a difference.
I made a vent for my main fuel tank using a rollover vent from Summit and putting it in the filler neck. I ran a piece of hose off the top of it and vented it right beside the overflow tube from the fill cap.
Good luck and keep us posted on what you come up with.
One more thought... Whatever setup you come up with, It would be a good idea to flow the system. I flowed mine from the surge tank, basically flowing the in-tank pump through the surge tank. Then I connected everything back up and let the in-tank pump fill the surge tank, and flowed from the return off of the regulator. In my static test I was able to get about what the published data was on each pump. Apparently something wasn't correct in the dynamic situation!
Clint, are you advocating against this now? If I mount it in the trunk, I essentially need to just fabricate a tank out of aluminum and buy some fittings. I can reuse existing high pressure pumps, use another pump I already have for the low pressure, there would be zero screwing with the wiring since I have a 60A solenoid right next to the gas tank which runs the two pumps currently.. would be a nonissue to add a low-amperage 3rd low pressure pump to that circuit. Won't even have to cut or modify any sheetmetal as there is already a hole in the trunk floor where the factory high-point riser was located on the vent line before the line continued forward to the engine bay to the charcoal cannister. The most arduous task would be pulling the rear seat back cushion to install a firewall between the seat & trunk.
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.
I think that was part of the humour. That being said, I read a handful of pages when I'm on the can.. I've done a lot of good learning in the bathroom.
The Internal Combustion Fundamentals is definitely scientific.. I'm surprised it doesn't have calculus in it. The Forced Induction Performance Tuning is very informative and technical, but not boring.. still learning some things from it page by page.
I have a couple more books on the way, not as textbook-y as those two but should be good reads.
Here's another example of 180 headers on an LSx in a mid-engine truggy. Build thread here.
I have seen some examples for SBC that pass the two crossover tubes under the oil pan, but it's almost always spaghetti and by the time you achieve equal length primaries (assuming that's your goal), they're too long to be effective in any useful RPM range.
01-16-2017, 07:44 AM
But please keep us posted, because I would like to see what you come up with!! 
