Winging a 1971 K5 Blazer L96 6L90 Swap

[HotRod4me]

Had to cut the output shaft on the 6L90 to fit into the Advanced Engineering adapter.

[HotRod4me]

Jim- You talked me into the polyurethane motor mounts. Hoping to get them mounted permanently in the frame with the motor, trans and transfer case this weekend.

[HotRod4me]

Made some good progress over the weekend. Got the motor, transfer case and transmission and LS radiator installed.

[HotRod4me]

Had to make a bracket for the transfer case. installed a 3/4" adapter plate and moved the transfer case back a total of 1-1/4", which moved the motor back a 1/2". I took a number of measurement and hoping nothing will interfere with the firewall. It will be close, but I think it will be ok. Anyone out there do a similar swap and can verify the clearance?

[HotRod4me]

Eliminating the long emergency cable guide, since the cable would rub on the driveshaft after moving the transfer case back.

[HotRod4me]

Dirty Dingo LS motor mount and Energy Suspension polyurethane clamshell motor mounts.

[HotRod4me]

Pulled wiring harness off and sent out to Easy EFI Solutions. Using the stock e78 ecm with my converted wiring harness.

[HotRod4me]

With the additional Horsepower from the L96 motor, I decided to build a driveshaft loop for the Blazer tonight.

[1rippen6]

How did you modify your tank for the fuel system? Thanks

[HotRod4me]

Thanks for checking out my build 1rippen6. The tank modification is explained further in the last post on the first page of this build thread. I used the stock tank and cut the hole for the sending unit with a large hole saw. After the hole was cut I welded in the retaining ring to make sure it was a solid mount. Please let me know if you have any further questions or need any measurements.

[1rippen6]

Originally Posted by HotRod4me

Thanks for checking out my build 1rippen6. The tank modification is explained further in the last post on the first page of this build thread. I used the stock tank and cut the hole for the sending unit with a large hole saw. After the hole was cut I welded in the retaining ring to make sure it was a solid mount. Please let me know if you have any further questions or need any measurements.

I'm good, I don't know how I missed it the first time, lol.

[HotRod4me]

Made a little more headway tonight. Got the front sway bar figured out and mounted. Since I did a 2" suspension lift, I had to reconfigure the way the sway bar mounted. I extended the bolt and used an 1-1/4" spacer. To mount it to the frame I ended up using a couple old transmission mount brackets I had laying around. The brackets gave me roughly 1" more clearance and helped me clear the brake lines. Almost looks factory.

[Tuff Gong]

Your truck is looking amazing. What size tires did you put on?

[HotRod4me]

Thanks for the encouragement. I ended up going with Firestone Destination LT33x12.50rx15 tires. I obviously haven't drove on them yet, but think they have a good aggressive look and with the tread pattern I wont have to much road noise while driving. I was on the fence between these and BF Goodrich. I see a lot of guys running the BF tires on their trucks, but have had good luck with Firestones in the past- plus they were roughly $200 cheaper for the set of four.

[HotRod4me]

Made very small steps forward today. Ended up getting some heat shield protective boots for the plugs. The wires sit pretty tight against the shorty headers.

Quick question for guys that have done builds in the past. Has anyone had the exhaust system built without having the body on the frame? Just worried about clearance issues if I have this done without the body on. All input is welcome.

Thanks,
Andy

[13jraven]

Take this with a grain of salt - A few years ago, I did an L96/4L80 with a 3.73 gear in a NASCAR inspired late 70s C10 with a Fitech set up.

Set the motor and trans without the cab on the frame and had no issues with the cab clearance. I know 2WD vs 4WD and 1st vs 2nd gen - hence the "take this with a grain of salt"

The issue I had is the L96 ran hot and was a thirsty ***** with the 80 pound injectors and the tune. I had to go back and do some heat displacer matting on the firewall and the inside of the cab.

My tuner buddy swears by the 6L90 - says they handle a ton of HP/TQ in their stock form. Way past what they are rated for.

[HotRod4me]

Thanks for the input 13JRAVEN. I think the clearance will be good and love the square body tribute truck.

Had a little stall on my build while waiting for my wiring harness and ECM to come back. I've been spending my time getting my wife's 1968 Chevelle SS motor freshened up and converting the front brakes to disc brakes. Hoping to get the exhaust built for the Blazer in the next couple weeks and then fit up the body. I'll keep you posted with hopefully good progress on both.

[NDM]

Originally Posted by HotRod4me

Picked this 6.0L L96/6L90 motor out of a 2019 Silverado 2500hd with 4 miles on it this fall.

Hey bud. I just bought a 72 Blazer and plan to swap it. I am not far from Beloit. I was wondering if you could share with me your source on the dropout motor and trans. My place in Elgin Il does not currently have one. I am itching to get started on mt Blazer to have it ready before winter.

What was the cost on the combo?

I put a L96 and 6l90e in my 76 Buick Regal and want to repeat the same setup in my Blazer for simplicity. This combo cost me $3800 for the motor and trans in2020

Thanks for any help in advance.

[NDM]

Any updates on this?

[yote1234]

im interested in the motor if original 71 350cu