Build Thread 1983 CJ7 FRANKEN-J build

[Armyvet25]

also bought all new leaf spring shackles and bushings

 

[Armyvet25]

Never used either of them, but I like the first set (black ones with the triangular piece in the center) vs. the separate tubes. Any idea if that triangular part is solid or not? I assume not because of what appears to be a welded seam down the bottom of one as seen in the pic. But I'm also sure the tubes on the other set are hollow as well. When I did my SBC swap, I kept the stock 304 mounting points on the frame, used SBC mounts on the engine (for an '84 Chevy PU), and used 1/4" plate to make some adaptors that also had extra holes to allow front/back adjustment a bit. Cost me nothing but some scrap metal and an hour or two of time cutting to size and drilling some holes. My engine is 420hp and I've never had any issues with this mounting.

do you have a write up on this with a few more detailed pics, I'm thinking maybe doing the same, but are the 6cyl welded mounts on a YJ frame the same as what you used?
Also...Congrats Mr. "Red Letters" lol

 

[TSB8C]

I do not have a write-up or other pics, sorry. My CJ had the AMC 258 i6 / 4.2l 6-cyl in it before the SBC swap. Not sure of mounts on a YJ frame vs the CJ frame. I simply used some 1/4" steel plate about 7" by 5" rectangle shaped. I drilled holes about 1.5" in from one end to line up with the mounting holes in the frame welded mounts. I then drilled a series of holes about an inch apart toward the other end of the plate that would line up with the SBC engine mounts. So this allowed me to mount the plate to the frame mounts, and then select the best position to mount the engine (using the standard SBC mounts) an adjust forward or back an inch at a time, getting the best position for distributor clearance at the rear and also fan clearance at the front.

So bolt your engine mounts to the block, bolt the rectangular pieces to the welded frame mounts, then drop the motor in and determine your best alignment, and then run bolts through the rectangular mounts into the engine mounts on the block. Easy-peasy and just two pieces of scrap cut to size and some holes drilled.

 

[Armyvet25]

If I understand this right, you use both the sbc engine mount for the engine and the sbc lower frame mount and your new plate goes between the lower frame mount and the Jeep's welded bracket using the plates holes for alignment?

 

[Armyvet25]

New leaf spring u-bolts front and rear arrived today!!!! Getting close to starting on the frame, looks like I need to order new rear upper shock mounts though, 1 broken bolt plus they area right where I have to do a minor patch both sides.
And, 5 bolts away from pulling the sbc 350 out of the Silverado for Franky, rough going though, hoping to have it on an engine stand by noon tomorrow.

 

[Armyvet25]

So bolt your engine mounts to the block, bolt the rectangular pieces to the welded frame mounts, then drop the motor in and determine your best alignment, and then run bolts through the rectangular mounts into the engine mounts on the block. Easy-peasy and just two pieces of scrap cut to size and some holes drilled.

I'll probably take some pics before installing, to show you, might make it easier for me to understand what you did, I was even considering just making some 1/4 in wedges and use the motor mount from the chevy, cutting off the oem frame mounts

 

[TSB8C]

I crawled under there and took a few shots. Never took any pics when I was actually doing the engine swap (sorry). Here's a good shot (I think) of the driver side mount from underneath. The blue shaft is my Borgeson steering shaft. You can see the 1/4" steel plate (some scrap I had laying around), the original welded mount on the frame with some bolts going through the steel plate. There are nuts and washers on the other side of the plate you can't see. Then you see a bit of the SBC engine mount showing from underneath and a bolt going through the steel plate into the SBC mount. You can see that my engine mounts (the SBC ones) are a bit forward of the stock welded mounts on the frame where the AMC 258 i6 / 4.2l used to attach.

Here's the driver side again from a front angle. You can see the harmonic balancer at the upper left for reference. You can see the frame welded original mount, the steel plate, and the SBC mount attached to the engine and the bolt going through the plate. I also circled one of the stock SBC mounting bolts (there are three) that attaches the mount to the engine. Again you can see that the SBC mount is in front of the original frame welded mounts used for the AMC 258 i6 / 4.2l .

And here's a shot of the passenger side mount, again from a front angle. Oil pan at the lower right, right side a bit less than half way down is the mechanical fuel pump block off plate, the lighter colored aluminum at the far upper right is part of the serpentine belt accessory brackets, and you see the SBC mount (one bolt circled), the plate, and the stock frame welded mount.


The plates are literally just flat 1/4' steel plate with a hole drilled toward one end such that the bolt needed to attach the SBC motor mount allows the mount to be almost flush with the edge of the plate (toward the front). Then a few inches back there are a series of two holes (one up and one down as shown in the first pic) that match the holes in the stock frame mounts, but repeated about an inch apart to allow back and forward adjustment for engine placement. Because I have a 700R4 auto Transmission and an adaptor for the Dana 300 , creating a lengthy drive line, I needed the engine as far forward as I could get it and still squeeze in my Contour dual electric fans so that my rear drive shaft wouldn't be too short.

This setup has been in place for about 4 years now. My engine is 420HP and I use it. This homemade mounting has held up just fine with my heavy foot. Hope this is helpful.

 

[Armyvet25]

I crawled under there and took a few shots. Never took any pics when I was actually doing the engine swap (sorry). Here's a good shot (I think) of the driver side mount from underneath. The blue shaft is my Borgeson steering shaft. You can see the 1/4" steel plate (some scrap I had laying around), the original welded mount on the frame with some bolts going through the steel plate. There are nuts and washers on the other side of the plate you can't see. Then you see a bit of the SBC engine mount showing from underneath and a bolt going through the steel plate into the SBC mount. You can see that my engine mounts (the SBC ones) are a bit forward of the stock welded mounts on the frame where the 258 used to attach.
View attachment 76608
Here's the driver side again from a front angle. You can see the harmonic balancer at the upper left for reference. You can see the frame welded original mount, the steel plate, and the SBC mount attached to the engine and the bolt going through the plate. I also circled one of the stock SBC mounting bolts (there are three) that attaches the mount to the engine. Again you can see that the SBC mount is in front of the original frame welded mounts used for the 258.
View attachment 76609
And here's a shot of the passenger side mount, again from a front angle. Oil pan at the lower right, right side a bit less than half way down is the mechanical fuel pump block off plate, the lighter colored aluminum at the far upper right is part of the serpentine belt accessory brackets, and you see the SBC mount (one bolt circled), the plate, and the stock frame welded mount.

View attachment 76610
The plates are literally just flat 1/4' steel plate with a hole drilled toward one end such that the bolt needed to attach the SBC motor mount allows the mount to be almost flush with the edge of the plate (toward the front). Then a few inches back there are a series of two holes (one up and one down as shown in the first pic) that match the holes in the stock frame mounts, but repeated about an inch apart to allow back and forward adjustment for engine placement. Because I have a 700R4 auto trans and an adaptor for the Dana 300, creating a lengthy drive line, I needed the engine as far forward as I could get it and still squeeze in my Contour dual electric fans so that my rear drive shaft wouldn't be too short.

This setup has been in place for about 4 years now. My engine is 420HP and I use it. This homemade mounting has held up just fine with my heavy foot. Hope this is helpful.

Now I got it, but...YJ frame mounts are different, same won't work, I'm going to explore a few similar options but I believe I'll be grinding off the OEM mounts and either going the aftermarket sbc mounts or making my own and utilizing the factory engine mount.
Thanks for the details and the extra pics.
My drive line is pretty long as well with the Chevy 5spd and NV3550, I may have to do the SYE, but will check first.
I'll probably run one larger electric fan

 

[TSB8C]

Yes, you do have a long drive line to deal with. I tried a single electric fan on mine initially and still had overheating issues. The Contour dual electric was a perfect solution. Slim, dual fans and dual speeds, fits the SBC version of the CJ radiator perfectly, and readily available brand new on Amazon for cheap.

 

[Armyvet25]

My frame mounts

Yes, you do have a long drive line to deal with. I tried a single electric fan on mine initially and still had overheating issues. The Contour dual electric was a perfect solution. Slim, dual fans and dual speeds, fits the SBC version of the CJ radiator perfectly, and readily available brand new on Amazon for cheap.

I'll look into those, also, here's what my mounts look like on a YJ frame

 

[Armyvet25]

I take it moving it that far forward didn't give you any oil pan to axle clearance issues.

 

[TSB8C]

I take it moving it that far forward didn't give you any oil pan to axle clearance issues.

As long as you have a "truck style" oil pan on that SBC, no issues. The oil pan has the sump at the rear. Many of the "car versions" have the sump at the front or even a full length sump. These will hit the front axle. I also have a 4" lift. So more clearance from that as well.

 

[Armyvet25]

As long as you have a "truck style" oil pan on that SBC, no issues. The oil pan has the sump at the rear. Many of the "car versions" have the sump at the front or even a full length sump. These will hit the front axle. I also have a 4" lift. So more clearance from that as well.

cool, I'm using a truck 350, and will have approx 3" body lift and a couple suspension. Will raise motor accordingling, making sure whatever mounts I make I can add spacers to lift.

 

[Armyvet25]

Motor pulled from donor..wahoo, actually went smoother than anticipated. sold some parts from donor and scrapped the rest, got half my money back from initial purchase.
Picked up a new-ish HEI distributor, billet style valve covers, ubolts for suspension came in.

 

[Patrick]

Now I got it, but...YJ frame mounts are different, same won't work, I'm going to explore a few similar options but I believe I'll be grinding off the OEM mounts and either going the aftermarket sbc mounts or making my own and utilizing the factory engine mount.
Thanks for the details and the extra pics.
My drive line is pretty long as well with the Chevy 5spd and NV3550, I may have to do the SYE, but will check first.
I'll probably run one larger electric fan
View attachment 76616

That’s a hell of a long driveline. Find you an AX15 tranny and buy back your Dana three hundred. If using driver’s side front axle, they’ve come up with some good flip kits.

Now I got it, but...YJ frame mounts are different, same won't work, I'm going to explore a few similar options but I believe I'll be grinding off the OEM mounts and either going the aftermarket sbc mounts or making my own and utilizing the factory engine mount.
Thanks for the details and the extra pics.
My drive line is pretty long as well with the Chevy 5spd and NV3550, I may have to do the SYE, but will check first.
I'll probably run one larger electric fan

 

[Armyvet25]

That’s a hell of a long driveline. Find you an AX15 tranny and buy back your Dana three hundred. If using driver’s side front axle, they’ve come up with some good flip kits.

um...no, lol, probably do a SYE once I realize the final length of the rear drive shaft.
I'm betting the Chevy 5 spd from a 91 Silverado is probably a lot stronger than an AX15, I could be wrong, but the combination I'm using was made for and can withstand a stock sbc350, I know others have done mixed combo's with great success, I'm betting my axles will be the first to suffer if I beat on it.

 

[Patrick]

Sure.

 

[Armyvet25]

Correction, must have been tired when I typed my drivetrain combo, I have a NV3500 Chevy 5 speed and NP241c 32 spline all behind an 88 350 Vortec

 

[Patrick]

You are still tired.

 

[Armyvet25]

You are still tired.

what did I get wrong?