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Fuel starvation cure for me... [message #349440] Sat, 19 October 2019 19:21
skip2 is currently offline  skip2   United States
Messages: 544
Registered: September 2011
Location: Winter Haven,FL (center o...
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Senior Member
Evening all, I've been working on a fuel stavation cure for low tanks when FI is used.
I originally set up my Fitech with the command center and worked for the most part ok but the early command center had it's own issues. The actual Fitech unit itself has never really had any problems other than those caused by fuel delivery to it. When I removed the command center I put an airtex pump on the frame rail and returned fuel to the tank through a fitting the PO had put on the fill neck. Still had issues at low tank so I never let it get below 1/2, the best I could tell. Took my spare airtex pump and set up with a pump on each tank and a selector switch, always had a spare ready to go if one failed. Worked pretty good but still had to be quick on switching when I would forget to switch. Tried running just on front as has been suggested. worked but the starvation would happen at the wrong times. I research and found a product from Holley called Hydramat, best to go to their site for a full description, if any one has already posted this set up I apologize. I used the Holley part 16-105. the only one that will squeeze in our tank opening, used an Earls AT165206ERL fitting in the top of it and put it on the bottom of a new fuel pickup and sending unit from JimK which had to be modified, but if your sending unit is erratic I think it's worth it. Had to go to a different fuel pickup because the stock has sending unit on the side of the pick up tube and the one from JimK it's on the bottom of the top part and you can cut the tube off as needed. I followed the direction Holley printed for installing in a 73-87 gm truck tank. I measure from the top of tank to the high spot in the bottom and got 4 3/4 inches I cut the pick up tube at a hair under 3 1/8 inches. That worked for me I suggest double checking what will work for you. When putting in tank be sure and put sending unit in at the same time as the Hydramat, don't ask how I learned that. Also you want to mark front to rear on sending unit so you orient the mat properly, front to rear.I put it all together in the rear tank since that is the one I have the access in the floor already. I only had on 1 inch of fuel over the high spot in the tank and I drove it on about 10 miles stop-start, some pretty good turns and no signs of starvation. The only thing I could do to make it better would be to tie the tank drains together, like Jim B suggest. The last time I came in from the road I was on front tank because it didn't like to run on the rear it was so low. After this mod I ran 10 miles, like I said. The only other hint I can give is get the kent moore tool for the retaining ring, it's a major help. Like I said go to Holley's site to understand how it works. I'm trying to download some pics to the photo site but not having much luck. If you PM me I'll be happy to send them to you. Hope this info will help someone the hardest part is getting to the unit and the cost. Also when I talked to Holley about the way the fuel can boil in the rear tank they said it should be no issue and possibly help with the problem.
Skip Hartline


74 Canyon Lands, FiTech, 3.7 FD LSD, Manny Tranny, Springfield Distributor, 2001 Chevy Tracker Ragtop Towd
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