72 blazer ls swap

[black_k5]

So I'm fare lyrics new to the site and purchased my blazer about 6 months ago. I love driving it so much I did a lot of research on this site and decided I would try my first ls swap. I will start by saying thank you to everyone for all the info. I'm hoping that this build might help someone else. After gathering some parts I started my project right after Christmas.

Since I did not want to stop driving the truck and wanted a lift kit I decided to start with a second frame. After having it sand blasted we added some bracing to help stiffin the body for towing. I decided to use a 31 gallon tank from a 87 blazer to be able to have an in tank fuel pump. To mount it I took 2 pieces of 2x2 angle and welded them together. This aligned to the rear set of rivet holes for the bump stop mounts. The original gas tank brace will need to also be moved back to fit the tank. This aligned with a set of holes already in the top of the frame to give you a reference point.

[black_k5]

Here is some on the reinforcement I did to the frame. The biggest improvement came from boxing in the original crossmember. For that I used a piece of 2x3 square stock and cut it to fit.

[black_k5]

Once the gas tank was fitted it was time for paint and reassembly. I por 15 everything then top coated with Eastwood chassis black but had issues with drying, it took over a week to cure. Not sure that was a good combo to use. After that the 4" rough country lift was installed with 3/4 ton axles from a 86 suburban

[black_k5]

I landed a 2002 suburban with 140k miles. 5.3l and 4l60e. Since my blazer has a np203 I decided to go back to a np205 and bought the AA adapter kit. I was going to fabricate a new cross member but due to time I ordered a dirty dingo crossmember. Once that comes in I can start on the brake lines.

[black_k5]

As for the fuel system I decided on trying the poly fuel lines after reading hemi43's thread. I bought a factory sending unit for the 87 blazer and cut off the flare fittings. Dorman sells a repair kit that has 2 12" lines with the quick connect ends. You can cut them to length then use a flaring block and swage to expand the pipe. Then brazed them together with 45% silver braze. Then added an Acdelco ep381 fuel pump that plugs right into the sending unit. I still need to find a fuel filter that has the quick connects. I think the early 2000s mustangs will work.

[GMC-YA68]

Looking good so far! You did your homework!

[GM man]

Originally Posted by GMC-YA68

Looking good so far! You did your homework!

Keegan, you didn't have to move your cross member to mount that 31 gallon tank, did you?

[GMC-YA68]

Originally Posted by GM man

Keegan, you didn't have to move your cross member to mount that 31 gallon tank, did you?

Yes, I moved it back a few extra inches but forget why. It may have been because the filler neck would have been right in the way of the body mount.

[black_k5]

Alright so I got the dirty dingo crossmember and proceeded to paint and assemble it. There are quite a few bolts. Also I'm showing the holes that had to be drilled in the frame to mount it. Notice that you use one existing hole to mount it and one of the other holes gets very close to an existing one. Theyou do provide plates that go on the outside of the frame which I haven't installed yet.

[black_k5]

Here is the motor installed. I used anchor 2292 motor mounts off rockauto for the frame. As for the motor side I ordered a set of IFS mounts to save some money from the dirty dingo mounts. I had to trim the tabs off the passenger side anchor mounts to allow for easier install. Since I'm running a truck pan it was very close to the crossmember as others have stated it would be. It the wording on the pan was grinder down it would allow for more clearance. I added 2 3/8" washers between the motor and IFS motors which comes out to around 1/8". I thought about making a steel plate for a spacer but the washer aren't loosing any surface area for mounting.

[SPIFFAV8]

Subscribed.

[black_k5]

Thanks Keegan. The idea of a second frame and the tank setup came from you. I've probably read your build about 15 times now.

[A1971Blazer]

Nice build....I'm subscribed....
Spare frame for me too....
I just got it in the shop and mounted to the rotisserie yesterday

[hemi43]

Looking good!! You won't regret using the ploy lines, just keep them away from chaffing and the exhaust. I used a standard fuel filter like the one on your 02 donor, because it used the same connectors as the ones on the fuel sender and fuel rail. BTW, we like lots of pictures !

[71meangreenc10]

Good stuff,

Post good pics of the fuel system. I am doing the same.

Smitty

[1rippen6]

subscribed

[black_k5]

Yes the cross member needed to be moved back or the gas tank would be over the axle.

[1rippen6]

I see the rubber mounts on the front tire take a picture installed on the inside of the frame rail maybe something there is switched around. I know someone will know how it should look if not I can find the picture in the body and chassis manual if it comes to that.

[GMC-YA68]

Here is what mine looks like. Maybe suck the bracket mounts down? I don't see any vertical bolts on yours.

[A1971Blazer]

Thanks...much appreciated...!
I think I have a TC mount from a '71 if I can find it....I will measure it. I'm using a NP241 TC so I won't need it.

[hemi43]

How do like those poly lines? I'll definitely use them again.

[black_k5]

I like them, they are very quick and easy to install! Plus the fact that they will never rust out. I was a little worried about them rubbing through but hopefully the wire loom will eliminate that issue. Thanks for the suggestion

[hemi43]

For what it's worth. For extra safety, I also tie wrapped the quick disconnects on the feed and return lines at the engine's fuel rail. I din't want to rely solely on the plastic clip to hold the line on, because it if should ever pop off with the engine running it could cause a fire. Just peace of mind IMO.

[DemkoG]

I ran the poly line in my LS Wagoneer swap. You are correct to secure the ends, They will not take any dangling load off the fuel rail. In a rush to get it on the road I did not secure the fuel line to the fire wall maybe 18-24 inches and it popped off maybe 18-24 inches. luckily no fire. I went AN fittings from the fuel rail to the filter Then ploy to the tank. As fair as the filter goes The C5 vett filters have a built in regulator witch makes life easier running one one line to the motor.

[black_k5]

Last Wednesday I drove the blazer over to my buddies house and took the the body off the fame. After a week of scraping all the undercoating and grease off the bottom of the truck and to my surprise no rust in the floor boards, just the rocker boxes. I painted the bottom with por 15 for protection.. After stripping the firewall I learned how to paint with single stage paint. I think it turned out pretty nice. Put the body on the new frame today but stI'll needs to be bolted down. As Smitty and Keegan said I did have to space the gas tank down. I found a piece of 1" square stock aluminum and installed it as a spacer. I tried to picture it before I set the body fully down. Sits a little high but I think it will look good with the top off. I may need new taller garage doors now.