Modding a C3 Gas Tank for a in-tank EFI Pump

BBShark

Garage Monkey
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I am converting my early C3 gas tank for use with a modern EFI fuel pump from a late model Tahoe. Also updating the fuel filler neck.

Step 1 - Drill a 4" hole
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I'm bound to do the same in the very near future. I Will follow this thread closely.
Is your tank lined with a rubber bladder?
 
Been so long since I did DPFI on my '72, I can't remember the exact sequence of events on the problems with the install.....but I can post the results for ME....

355 '89 roller truck block, L98 heads, headers, '94 vette LT1 injection run with a speed density computer from a '88-91? vette computer programmed outsourced.....factory # 1227730

and so, the obvious relays running the fuel pump that is tied to the rear frame rail, with rubber hose wrap to vibration isolate it hose clamp holds it.......filter is from stock fuel feed into the suck side of the pump....witch runs to the STOCK fuel line up forward..... and the stock fuel line return to the tank....no biggie...never have understood the conversations about that 'issue'

I don't understand the need for all this aftermarket in tank fuel pump setups...

running my way for some 20 years now....

:lol:

edit....I forgot that the stock evap setup is best served with the stock fuel valve on the left side of tank, and then into the charcoal can and since MY evap valve was defective in the OPEN position I just ran the hose to the intake above the throttle body....ported vac....... and I have a locked cap with open vent....no smells for years now...in garage for daze on end....
 
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Made an aluminum seal ring and clamp ring for the pump and some quick disconnect O-ring fittings.

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Tank pump installed, fuel filler, fuel filter, lines.

Working my way up to the engine and fire it up!

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I have my fingers crossed. Hard to find info for flow rate @ PSI but I have seen builds where people used these pumps. Also used a Delphi pump which is supposed to have better specs that the cheap ones.
 
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