jenifuriouSS

Hey I'm a fuel injection NEWWWB. Haha. Can anyone give me some advice/info or forward me to a different thread (couldn't find one) on how to modify the stock gas tank on my 87 Monte Carlo SS for EFI (just bought an LS1 and am in the process of swapping out the stock carbureted 305). I found a company that makes in-tank pump tanks that are really nice but they're $1200 and if can use my stock tank (which is only 2 yrs old) and save some cash that'd be great. What do I need to get to modify the tank for EFI? I'd rather have an in-tank fuel pump than an external one but is that going to require crazy amounts of fabrication? We are re-doing fuel lines and I'm going to high pressure lines and have most of the other plumbing figured out. Will I need to get a sending unit, and what's the deal with return lines and do I need one? Thanks for any help! Is there anything specific to swapping to EFI with an LS1 to think about or any specific parts that would be best to go with?
-Jen

code4

iTrader: (30)

Is it a steel tank? If so it would be easy to just add two bulkhead fittings to the bottom. One for an external fuel pump, the other for the return. You will also have to install a fuel pressure regulator on the return line to maintain 58 psi.

Lonnies Performance

iTrader: (16)

I'm currently putting a dual in-tank setup together for one of these. Once I have this scienced out, I'm sure the single will be much easier to accomplish.

Depending on your needs for lines, rails, regulator etc., I can put together a system for you with all components required.

Let me know if I can be of assistance.

bgblockelcamino

iTrader: (9)

i am thinking of using a grand national tank when i do my monte carlo. they can be upgraded to 255 in tank which will work great in almost any hot street car.

350SS

iTrader: (38)

You may or may not need to modify your tank depending on whether it has enough or any baffling inside. I'm planning to do a similar swap eventually with my 81 malibu and found a couple of options for sending units that fit the stock tank (which is the same dimensions as yours and other g-bodys):

http://www.gbodyparts.com/product_in...0a98dfdfcc4b47

http://www.gbodyparts.com/product_in...0a98dfdfcc4b47

If your tank doesn't have baffles, you should be able to find a tank for a tbi monte carlo or for a grand national (something that had fi) and use it with one of the senders above.

You can either do the fuel setup with or without a return line, depending on how the fuel rail is setup on the motor you bought. If the pressure regulator is located on the fuel rail, you'll have to run a return line back to the tank. If not you can either run a pressure regulator near the tank and return line back to the tank (which will be shorter) or run a corvette fuel filter which I believe has the pressure regulator built in.

I would suggest searching through some threads in the “conversions and hybrids” section here and would check out JohnB ‘s swap on his Monte Carlo.

https://ls1tech.com/forums/member.php?u=1099

Here’s some other links that might be helpful:

http://www.maliburacing.com/forum/index.php

http://www.maliburacing.com/forum/vi...ed665be96566bb

http://www.maliburacing.com/forum/vi...ed665be96566bb

Hope this helps