Saddle tank delete with carburation

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Bloodhound1981

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I did this with a 31 gallon plastic Blazer tank. The 40 gallon tank is the same footprint, its just deeper so it hangs down lower. This is on a EFI application (1981 C-10 frame). Had to remove the crossmemeber for the spare tire carrier, and add a new crossmember to support the tank. I also mounted the tank backwards from the way it is supposed to in a Blazer so that the filler is pointed towards the driver side. All in all pretty simple.

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scrap--metal

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Body swap to an M37.

Is there some kind of reason to keep them?
If it ain't broke, don't fix it. Leave the saddle tanks under the M37.
 

Camar068

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RecklessWOT

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Body swap to an M37.

Is there some kind of reason to keep them?
They already exist and hold fuel just fine. Is there some reason to get rid of them? Swapping is just more work and expense for no real gain.
 

Travlr

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They already exist and hold fuel just fine. Is there some reason to get rid of them? Swapping is just more work and expense for no real gain.
You know I'm doing a body swap... right? Putting an M37 body on the Chevy frame?
 

RecklessWOT

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You know I'm doing a body swap... right? Putting an M37 body on the Chevy frame?
I'm not intimately familiar with the shape of the underside of an M37 cab. What prevents the use of saddle tanks, the body still mounts above the frame, right? Are there things sticking down under it or something? If there's a reason then there's a reason, I'm not saying I know more about it than you do, but you could explain it for those of us that don't know. When I hear about someone doing a body swap my first thought isn't immediately "quick, get rid of the fuel tank!" so even though I read you were swapping the body, I still don't completely understand the reason for getting rid of them.
 

Craig Nedrow

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I remember our old power wagon gas tank was under the bed (flat bed) outside of the frame just a square tank. Seems like the square body tanks would work,
 

Bextreme04

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I did this with a 31 gallon plastic Blazer tank. The 40 gallon tank is the same footprint, its just deeper so it hangs down lower. This is on a EFI application (1981 C-10 frame). Had to remove the crossmemeber for the spare tire carrier, and add a new crossmember to support the tank. I also mounted the tank backwards from the way it is supposed to in a Blazer so that the filler is pointed towards the driver side. All in all pretty simple.

You must be registered for see images attach
The 40 gallon is NOT the same footprint.
The 31 Gallon is 28.75"x28.125"x12.75"
The 40 Gallon is 28.75"x35"x13.13"

Its only ~ 0.5" taller, but it extends and extra 7" longer and basically fits right up against(or maybe even a little bit over the top of) the rear diff. It can work fine if you have a decent lift on the truck and aren't planning on doing any crazy offroading, but it definitely is a lot closer than the 31 Gallon. I have the 31 Gallon retrofitted into my 1980 K25 and am running it to my carbureted engine currently. It will eventually get an EP381 pump dropped into it when I swap in the 454/4L80. I needed to move the forward rear spring mounts 4" forward in order to swap in 63" rear springs and I am also flattening the floors to better fit the seats I have for it, so it was killing two birds with one stone to put in the EFI blazer tank and remove the saddle tanks. It has worked well for over a year now.

I got the original crossmembers, mounting straps, filler neck, and filler door stuff with the tank when I bought it locally from a guy. He had cut it all out of a blazer at the wrecking yard with the intention of using it for a swap as well.
 

Bloodhound1981

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The 40 gallon is NOT the same footprint.
The 31 Gallon is 28.75"x28.125"x12.75"
The 40 Gallon is 28.75"x35"x13.13"

Its only ~ 0.5" taller, but it extends and extra 7" longer and basically fits right up against(or maybe even a little bit over the top of) the rear diff. It can work fine if you have a decent lift on the truck and aren't planning on doing any crazy offroading, but it definitely is a lot closer than the 31 Gallon. I have the 31 Gallon retrofitted into my 1980 K25 and am running it to my carbureted engine currently. It will eventually get an EP381 pump dropped into it when I swap in the 454/4L80. I needed to move the forward rear spring mounts 4" forward in order to swap in 63" rear springs and I am also flattening the floors to better fit the seats I have for it, so it was killing two birds with one stone to put in the EFI blazer tank and remove the saddle tanks. It has worked well for over a year now.

I got the original crossmembers, mounting straps, filler neck, and filler door stuff with the tank when I bought it locally from a guy. He had cut it all out of a blazer at the wrecking yard with the intention of using it for a swap as well.
Good to knpw, I was given bad intel.
 

Craig Nedrow

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The 40 gallon is NOT the same footprint.
The 31 Gallon is 28.75"x28.125"x12.75"
The 40 Gallon is 28.75"x35"x13.13"

Its only ~ 0.5" taller, but it extends and extra 7" longer and basically fits right up against(or maybe even a little bit over the top of) the rear diff. It can work fine if you have a decent lift on the truck and aren't planning on doing any crazy offroading, but it definitely is a lot closer than the 31 Gallon. I have the 31 Gallon retrofitted into my 1980 K25 and am running it to my carbureted engine currently. It will eventually get an EP381 pump dropped into it when I swap in the 454/4L80. I needed to move the forward rear spring mounts 4" forward in order to swap in 63" rear springs and I am also flattening the floors to better fit the seats I have for it, so it was killing two birds with one stone to put in the EFI blazer tank and remove the saddle tanks. It has worked well for over a year now.

I got the original crossmembers, mounting straps, filler neck, and filler door stuff with the tank when I bought it locally from a guy. He had cut it all out of a blazer at the wrecking yard with the intention of using it for a swap as well.
Eric, you gonna swap the 454 this winter? Your gonna love that. What is the motor out of?
 

Bextreme04

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Eric, you gonna swap the 454 this winter? Your gonna love that. What is the motor out of?
Hope so, I’ve been working on it slowly but surely and now it’s been sitting completed in the garage for about a year now waiting to go in, but something always ends up taking priority. Really hoping to do it this month. Engine/trans and wiring harness came from a 97 K2500 Suburban.
 

Craig Nedrow

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Pictures? What I just finished for my good wife.
 

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