72 Cummins swap
 

Trying to figure out what to do for a fuel tank. I would like to swap out the front seat to newer one and move the seat rearward. I'm going to run 4" exhaust over the rear axle so a near mount tank is kind off difficult without making a custom tank. Plus I think I will run nerf bars but not sure if the saddle tanks will clear. What have other guys done? Looking for advice.[ATTACH]Attachment 1206231

Attachment 1206235[/ATTACH]

Re: 72 Cummins swap
 

So, I actually went with a 31-gal fuel tank from a square body suburban. It fits cleanly between the rails. I had to remove the back two cross members, turning one around to provide the front mounting bracket. As far as exhaust goes, it looked like I had more of an issue from the rear brake line bracket than from the exhaust. I've got a little bit of room, but not an extreme amount, and will be looking at the exhaust routing next.

The mounting of the tank is one the last couple of pages, but I can always take more pictures if you need.

Re: 72 Cummins swap
 

I have some pictures in my build thread when I stuck a 40 gal burb tank from a square body in my Longhorn. I had to move all the same things Scott did as well. I ended up ditching that when I went to air ride though. Now I have to build a tank for it. :lol: By the way, nice swap you have going.

Re: 72 Cummins swap
 

Is your truck 4x4? If it is and is lifted at all then I'd think you could run a rear mount tank and still have room for 4" exhaust. I installed a 25 gal. square body burb tank in my '71, and after moving those rear crossmembers it fits like a glove...but I had absolutely no room for exhaust back there since mine's 2wd and lowered 5.5" in the rear.

I picked the 25 gal. tank because it only hangs down a few inches below the frame rails, whereas the 31 gal. & 40 gal. tanks hang lower.

Re: 72 Cummins swap
 

Forgot to give ya the specs. 72 short wide 93 12 valve, nv4500, 205, 60 front and 70 rear 4" lift . Not sure if the rear tank will clear the 4" being a SW box. I'll post more, newer pics later. Everyone likes pictures.

Re: 72 Cummins swap
 

From my thread...


I've done some cursory measurements, and also checked online. There are three sized tanks that the Suburbans came with:
25 Gallon: 28-3/4" x 28-18" x 10-3/4"
31 Gallon: 28-3/4" x 28-18" x 12-3/4"
40 Gallon: 35" x 28-3/4" x 13-1/8"
(Sizes verified on LMC Truck, O'Reilly & Napa Auto websites)


I decided to go with the square-body suburban 31 gallon gas tank. That required a little bit of fabrication on the back end of the truck.

To start, the rear cross-sill (the one with the light plug) came out, and was rotated 180-degrees, and became the front brace for the fuel tank.
https://lh3.googleusercontent.com/-H...o/IMG_0811.jpg

https://lh5.googleusercontent.com/-l...o/IMG_0812.jpg

This effort was followed for quite some time with lots of measurements. I needed to have the fuel neck clear the frame, but at the same time not be so tall as it would bump into the bottom of the bed. Likewise, I needed to play with it front-to-back as so to sit between the bed rails. Once that was done, I finished the calculations and made the brackets.

https://lh3.googleusercontent.com/-D...o/IMG_0816.JPG

https://lh3.googleusercontent.com/-Y...o/IMG_0833.JPG

https://lh3.googleusercontent.com/-n...o/IMG_0834.JPG

Then it was a matter of getting it into its final resting place.

https://lh6.googleusercontent.com/-S...o/IMG_0836.JPG
***Note: The rear brake line is a temporary solution, and will be getting adjusted either today or next weekend. I'll re-work the bracket and provide more substantive support across the frame before joining to the soft-line on the axle.

https://lh6.googleusercontent.com/-P...o/IMG_0837.JPG

Re: 72 Cummins swap
 

In that case I'm not sure that any of those tanks would fit in a short bed. Might be more logical to run a 67-72 suburban tank.

Re: 72 Cummins swap
 

Got my IC pipes done but not sold on the color. Might powder coat later. Anyway I think they turned out OK.
Attachment 1208616
Attachment 1208617
Attachment 1208618

Re: 72 Cummins swap
 

Pipes look pretty darn clean to me.

Re: 72 Cummins swap
 

Looks really nice!

Re: 72 Cummins swap
 

subscribed!

Re: 72 Cummins swap
 

Got my cab back from the blaster the other day.
Attachment 1240229
Attachment 1240230
That blasting sure finds the rust. I knew I needed floor board and rockers but found some rust under the windshield. Looks like I need to find a donor cab to cut part of the windshield frame out and weld into mine. In less somebody has a better idea.
Attachment 1240231

Re: 72 Cummins swap
 

Yeah, sand blasting will sure find any soft spots in the metal. If you look in the 67-72 parts section on here, you might find a cab someone is cutting for patches and you might be able to get one that way.

Re: 72 Cummins swap
 

Took so more pictures with the cab off.
Attachment 1240629
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I cut the top two rows out of my IC to make it fit.
Attachment 1240628

Re: 72 Cummins swap
 

Nice job! Any idea on what you'll end up having invested in just the Cummins swap?

Subscribed!

Re: 72 Cummins swap
 

Not sure on the investment. I am keeping all receipts from everything but scared to add it all up. Maybe some day.

Re: 72 Cummins swap
 

Don't add it up until you can drive it. Just speaking from experience. It might make ya cry. :lol:

Re: 72 Cummins swap
 

Great project! Keep up the good work!

Re: 72 Cummins swap
 

Keep it up, looks great! With your transfer case linkage did you have to cut the floor at all? Or did it stay inside the opening? I have an nv4500 and 29
Spline np205 and with the advanced adapters bracket it sticks the tcase shifter pretty far away from the transmission shifter

Re: 72 Cummins swap
 

Both shifters came out different. Just a weld and cut job for the new openings.
Attachment 1286122

Attachment 1286123

Re: 72 Cummins swap
 

great project and I'm Subscribed to this one! could you show a couple of pictures of you engine mounts please!

What color are you going with?:metal::metal:

Re: 72 Cummins swap
 

I used a engine mount from autoworld. I'll see if I can get some pic's for ya. I think I'll keep the color the same. The truck was my Dad's bought new in 72.

Re: 72 Cummins swap
 

Back to your original post. I don't blame you for removing the tank from the cab but you won't gain any more room to move the seat back. All the seats always hit the cab above the tank before they hit the tank. Unless you want a seat that sits at a 90 degree upright there's nothing to gain

Re: 72 Cummins swap
 

Not sure if I'm going to use the factory tank or not for sure yet. But was thinking more of room for some speaker boxes. Try to hear over the diesel noise. Speaking of that is anyone running a flowmaster diesel muffer and what does it sound like. Got a 4 inch on mine and sounds cool but not sure under load what it sounds like.

Re: 72 Cummins swap
 

Ok just didn't want you getting your hopes up! But yes that space is definitely useable for something.

Also you said your using a cummins from a 93?

From my limited time in the diesel world but aside from the looks of a 4" I don't think you will gain anything performance wise from it. I thought that only mastered once you get up over 500-600 horse power or something. Just a thought maybe you can split it or something?

Again I'm no diesel mechanic just throwing it out there

Re: 72 Cummins swap
 

Here is the only Pics I got.
Attachment 1297588
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Attachment 1297591

Re: 72 Cummins swap
 

Hey Thanks for the Pictures!

Mine is a 2WD and will use a slightly different configuration, but I will be getting a hold of AutoWorld in the morning to order my set! I have used their mounts quite a few times in three Super Duty conversions and a mid 80's Chevy 4x4 cummins conversion!
Great products with friendly and fast service!
AutoWorld is #1 in my book

I need to have the Admin move my build from the 67-72 section to the Diesel Conversion section!
Keep up the great work!:metal::metal:

Re: 72 Cummins swap
 

I moved my tank to the rear for the purposes of being able to fit a sub behind the seats. And every inch of added storage space is a positive in these small single cabs. Unfortunately, ive found that the un-muffled drone of the cummins engine basically overpowers my stereo at cruising speeds.

Mine has the 31 gallon tank from a 1985 blazer, but i am considering swapping it for the 25gal just to save the few inches of vertical clearance...

Re: 72 Cummins swap
 

Very cool build. I am using fuel cell sitting in the bed of my truck. Might not be perfect for if you want to use your bed but would give you plenty of room for your exhaust. Good luck on your build

Re: 72 Cummins swap
 

Well I got my engine mounts from Auto World the other day and what a great fit and finish! Now to move on to my Rusty Rocker panels !

A mid 70's Blazer gas tank is going in the back between the frame rails for my tank problem !
Sorry about the hi jack!

Hows your project coming along?

Re: 72 Cummins swap
 

Ya thinking about building a tank to go under my toolbox. The old man already cut a hole in the bed for a bed tank. Playing with ideas.

Re: 72 Cummins swap
 

That Autoworld stuff is great built stout!! Ya I got the driver side rockers and cab corner on and finishing up the floor pan and off to the other side. Fun stuff.

Re: 72 Cummins swap
 

Any updates? Very nice build! Also do you have any pictures of hood latch support mods and radiator support mods to run the second gen Intercooler?

Re: 72 Cummins swap
 

Found some pics. I can get more.
Attachment 1329108
Attachment 1329109
Hope that helps. I cut the top two rows off of my intercooler and welded.

Re: 72 Cummins swap
 

Finally got back to this project this past weekend. Still working on the cab. Cutting out the rust and welding in new panels. Been busy stocking the freezer with salmon. Did get some time to get these. Figuring on mounting them in the pillar.
Attachment 1329110
Attachment 1329111
Attachment 1329112

Re: 72 Cummins swap
 

Nice gauges. Salmon huh, what river do you get them out of? That sure sounds good to have in the ol freezer.

Re: 72 Cummins swap
 

Attachment 1366092
Got some time to work on the old girl.
Attachment 1366097

Re: 72 Cummins swap
 

Nice work! That looks great!

Re: 72 Cummins swap
 

Cleaned the garage out and found my other project.

Attachment 1367762

Re: 72 Cummins swap
 

74 nova. 425 + HP 383 SB. Ended up with a free car and had to build a cool engine for it. Its funny how a free project ends up costing a small fortune. Humm... Head scratcher.