Author Topic: 1985 to 1987 Fuel tank & pump LS swap ... do myself or buy kit  (Read 373 times)

Offline dogfacedsoldier

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1985 to 1987 Fuel tank & pump LS swap ... do myself or buy kit
« on: September 14, 2018, 09:13:53 AM »
I have completed an LQ4 swap into my 85 C10.

I'm currently running an external pump to the left tank (stock fuel lines run from engine to left tank & relay, to right tank).  I originally wanted to find a way to run both of my tanks with in tank pumps, but as I dig dealer into the mods, the novelty vs. work/$$$ ratio doesn't make much sense (could put that time and $$$ elsewhere).

So I am going to run fresh lines to the right side, as this is more of a clean slate than running to the other side.  I will plug the stock lines to/from the left side, in case I change my mind about tackling dual tanks.   

I have checked out the conversion posts, installing a stock 1987 baffled tank, modified stock 87 sending unit, and upgraded pump. 

There are also a couple ready to go packages, offered by Holly and others (though, I suspect that the "others" are simply advertising the Holly product?). 

Input is greatly appreciated.

Has anyone used the Holley package?  Is there any benefit to using their product over a stock '87 parts swap? 




Online VileZambonie

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Re: 1985 to 1987 Fuel tank & pump LS swap ... do myself or buy kit
« Reply #1 on: September 14, 2018, 04:05:06 PM »
I would only run in tank pumps, replace the hoses with pressure rated hoses and the selector valve. EFI rated clamps are a must as well. If you don't want to change the tanks, just keep the fuel level over 1/4 full.

You can also make your own baffle similar to modern style sending units that are part of the in tank assembly

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Offline 75gmck25

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Re: 1985 to 1987 Fuel tank & pump LS swap ... do myself or buy kit
« Reply #2 on: September 19, 2018, 07:10:16 AM »
The Holley sells their hydramat "fuel mat" that is supposed to work like an in-tank baffle to keep the pump supplied if you use your existing tnak.  However, I don't know anyone who actually has one.  It also costs in the range of about $150, so its not a cheap option.  I think you could buy an '87 tank with a baffle for about $150. In any case, you still need to buy the in tank pump also.

Another option is to install an external sump or surge tank, which is usually about 1-2 quarts in size, and it both holds the high pressure pump and serves as an external sump for your current tank.  There are off-the-shelf solutions, like the FiTech Fuel Command Center, or you can buy an external surge tank for about $50 and build your own.   The FiTEch product also gets pretty bad reviews on Summit, although they supposed have a newer model that works better.

This is another alternative to an OEM FI tank.  http://www.tanksinc.com/index.cfm/page/ptype=product/product_id=561/category_id=144/mode=prod/prd561.htm  Most folks seem very happy with them.

Bruce
« Last Edit: September 19, 2018, 07:28:01 AM by 75gmck25 »

Offline roundhouse

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Re: 1985 to 1987 Fuel tank & pump LS swap ... do myself or buy kit
« Reply #3 on: September 20, 2018, 12:58:31 PM »
I got a 87 tank from Rockauto for under $100

Offline Irish_Alley

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Re: 1985 to 1987 Fuel tank & pump LS swap ... do myself or buy kit
« Reply #4 on: September 20, 2018, 01:26:20 PM »
RockAuto Rant good luck if you have to return anything to them
If you can’t tell yourself the truth, who can you tell it to?~Irish_Alley

When you have eliminated the impossible, whatever remains, however improbable, must be the truth ~Sherlock Holmes

Offline roundhouse

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Re: 1985 to 1987 Fuel tank & pump LS swap ... do myself or buy kit
« Reply #5 on: September 23, 2018, 05:52:15 PM »
RockAuto Rant good luck if you have to return anything to them
I agree

Don’t order anything from rockauto if it is a suspension part that wears out
Ball joints and stuff are cheap Chinese garbage
Or if you’re are positive it will fit your car
You will play heck getting your money back

The gas tank was fine though

Offline ehjorten

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Re: 1985 to 1987 Fuel tank & pump LS swap ... do myself or buy kit
« Reply #6 on: September 24, 2018, 08:42:55 AM »
I have never had an issue returning stuff to RockAuto.
-Erik-
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Offline dogfacedsoldier

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Re: 1985 to 1987 Fuel tank & pump LS swap ... do myself or buy kit
« Reply #7 on: October 02, 2018, 09:01:44 AM »
I'm not interesting in the fuel mat thing.... I'd rather replace with an '87 baffled tank. 

I considered the cost of the tank, pump/sending unit, upgrade pump, time to retro fit.... price is a little more palatable on sale, and packages are finally in stock. 

I just ordered this.  Holley Sniper EFI Fuel Tank System Part # 19-157

https://www.holley.com/products/fuel_systems/fuel_tanks/parts/19-157?msclkid=ab2eb351f42b144d0f08e8e28dec0dc3&utm_source=bing&utm_medium=cpc&utm_campaign=Google%20Shopping%20-%20Non-brand%20-%20Holley&utm_term=4574930445095840&utm_content=Holley%20-%20Sniper%20EFI


Offline Captkaos

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Re: 1985 to 1987 Fuel tank & pump LS swap ... do myself or buy kit
« Reply #8 on: October 05, 2018, 06:59:53 PM »
You would be ahead of the game by using the hydramat.  The baffled tank isn't that advanced in my opinion.  It is just a 4 sided plastic wall in the bottom of the tank.

Offline 75gmck25

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Re: 1985 to 1987 Fuel tank & pump LS swap ... do myself or buy kit
« Reply #9 on: October 06, 2018, 07:44:22 AM »
I agree that the hydramat is a great idea, but can't believe how much it costs.  The prices vary from about $150-$600, depending on the size you buy.  And you still have to buy a high pressure fuel pump and sending unit to use with it.

Bruce

Offline MrFiveOh

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Re: 1985 to 1987 Fuel tank & pump LS swap ... do myself or buy kit
« Reply #10 on: October 06, 2018, 08:25:41 AM »
Check out the page LS swapped c10s, has schematics, how to and other valuable info. its common a 87 tank with a walbro 255 in tank fuel pump is used on many swaps up to 550hp
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Offline Captkaos

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Re: 1985 to 1987 Fuel tank & pump LS swap ... do myself or buy kit
« Reply #11 on: October 07, 2018, 09:48:13 AM »
Although I don't recommend it, you can still use your external pump with this an the stock non-EFI sending unit and Hydarmat.. The BEST place for long fuel pump life however is in the tank submerged.  There are several that have done just this and found that it is just as expensive to skip the EFI tank and go with Hydarmat.
This is straight off of Holley's site, note it says C10 Longbed on the tank.