fuel tank replacement on my 81 malibu

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denny

Master Mechanic
Feb 4, 2017
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since they are not very costly, i plan on replacing my 81 malibu fuel tank sometime in 2020. would like to know what tank is in it now because i plan on the in tank 87 monte 4.3 f.i. tank with the drop in module. i run a n.a. q-jet crate motor now (375 hp). the current tank has a feed and return only. i will run a regulator with a return and would like about 6 psi. i used to have a 4.3 in an s-10 and it was tbi and ran a constant 12 psi all the time. i figure i can regulate that to 6 psi pretty easy. the f.i. tanks have a correct baffle. my 81 was a 267 c.i. with the computer. was wondering if i have a f.i. tank in it now or if this 267 came with tbi. seems like the stock tbi pump on the drop in module would do the job. opinions? thanks
 

spidereyes455

G-Body Guru
Mar 6, 2013
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Northeastern PA
At your power level with a q-jet and a sbc an electric pump isn't nessicary. You would just be spending a lot of money and putting in a lot of effort for no improvement.
 
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fleming442

Captain Tenneal
Dec 26, 2013
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Here's my experience; YMMV....
I did a Spectra EFI ready tank in my 67 442 (<----). The 5/16" return was too small, and I couldn't get my regulator below 9psi. I had to tee off to one of the vent lines at the rear of the tank to open up the return enough to get down to carb friendly pressure. I did this in anticipation of eventually going EFI- remove the regulator and go.
Now, on my G Bonneville, I used a TBI Monte tank with the baffle and a stock style replacement pump with -6 AN adapters on the sending unit. It works fine on the Series 2 EFI. The factory baffle sucks, so be prepared for that. Anything less than 3/8 tank around a hard turn will stall the engine/uncover the pickup, but it does work. The G tanks don't have extra vent ports to tee off like my A body did, so you may have to get creative or get a RobbMC sending unit that has larger lines....
 
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denny

Master Mechanic
Feb 4, 2017
279
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At your power level with a q-jet and a sbc an electric pump isn't nessicary. You would just be spending a lot of money and putting in a lot of effort for no improvement.
thanks for the reply. i have run two carter fuel pumps,one existing on the motor and one new one. both the same. this was a test because i can change mechanical pumps on this malibu in about 20 minutes. everything good for normal driving,about 5.5 to six. a little creep at street lights. when i stand on it out here in the country at about 5200 and up it drops to 2.5-3. i know the q-jets don't need that much but i want a steady 6 all the time. i can get that with a well thought out system. i'll be trying out my holley this summer so i want a solid fuel system. maybe efi some day also. thanks again.
 

denny

Master Mechanic
Feb 4, 2017
279
116
43
Here's my experience; YMMV....
I did a Spectra EFI ready tank in my 67 442 (<----). The 5/16" return was too small, and I couldn't get my regulator below 9psi. I had to tee off to one of the vent lines at the rear of the tank to open up the return enough to get down to carb friendly pressure. I did this in anticipation of eventually going EFI- remove the regulator and go.
Now, on my G Bonneville, I used a TBI Monte tank with the baffle and a stock style replacement pump with -6 AN adapters on the sending unit. It works fine on the Series 2 EFI. The factory baffle sucks, so be prepared for that. Anything less than 3/8 tank around a hard turn will stall the engine/uncover the pickup, but it does work. The G tanks don't have extra vent ports to tee off like my A body did, so you may have to get creative or get a RobbMC sending unit that has larger lines....
thanks for the reply. i do not like the 3/8 tank problem. i'm under there right now doing brake line replacement and i might just run a 3/8 line now while i'm under there. the monte tank was recommended because of the baffle system. don't like how the baffle sucks. might have to do some more studying so i can avoid the baffle and 3/8 tank problems. would like to do this once. thanks again.
 

pontiacgp

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Mar 31, 2006
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Kitchener, Ontario
a bypass regulator will work reduce the pressure to your carb.

cat_zm_32.jpg
 

Ribbedroof

Comic Book Super Hero
Supporting Member
Jan 4, 2009
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Wellston, OK
No Malibu (78-83) came with a fuel injected gasoline engine, so if it's the original, it's not set up for electric pump
 

pontiacgp

blank
Mar 31, 2006
29,270
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Kitchener, Ontario
That's what I was talking about, but you have to bleed off EFI pressure to carb levels. You're returning a TON of fuel.

I agree with you but he was asking for a solution and there are people using an efi pump for a carb which to me does not make any sense to me when there are proper pumps you can buy


and then if the pump dies you have to drop the tank whereas with a mechanical pump they rarely die without a warning to leave you stuck, the mechanical pump takes about 1/2 to change and you don't need to put the car up on jack stands...
 
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