I need help finding which LS to use on a 1946 Chevy Truck 1/2 ton

Daily Driver
As few modifications as possible.

Any suggestions?

 

Thousands of pages here to help,get reading...

 

Many modifications will be part of the project. Not sure you will have anything that just bolts up.

I used an L92 and 6L80 in my '51 Ford F1.

To name just a few of my solutions...
I bolted up a Holley 302-2 oil pan. The stock truck pan hung lower than the cross member by an inch or two. I still use stock intake manifold and snorkel, but adapted an after market cone air filter to ride in the passenger's wheel well.

I made my own trans crossmember, but it just bolts to the frame, so that's no big deal. You can buy a crossmember and bolt it in.

Exhaust - my frame rails are narrow, so I ended up with Corvette LS3 (gen 7) manifolds and then custom exhaust out the back. Most challenging part of the exhaust was all the pie cuts to clear the steering.
Brakes - 4 wheel disc with a hydraulic booster - not enough room on the frame rail to run a diaphragm booster - unless you want a multi-stacked one, but those are expensive.

I'd use the pedestal motor mounts if I did it again like you find on Gen 6 and 7 corvette. You'll want to box in your front frame and then can fab up an easy pedestal to have the factory motor mounts set on.

I used a $250 speedway aluminum radiator and adapted that to fit on soft rubber studded mounts from mcmaster. This required modifying the front horse-shoe member and then the radiator, too. To plumb it, I used several different radiator hoses joined together with aluminum tubing at the intersection to get the routing I sought. The hoses look factory, except with an extra set of hose clamps at the joint.

Mounting the engine and trans required a lot of researching, planning, measuring, fabrication, welding, plumbing, wiring. In short, virtually everything needs to be adapted to the old truck.
Also, heres a photo journal of my build.
https://www.icloud.com/sharedalbum/#B0s55Z2WMGOKzTn

Does any of that help?

 

Some of that was also Greek, However, it is not discouraging. I hope to learn all of that in this build.

A guy from Kansas put a LS1 in this truck and just had to move the ac bracket. I am removing a running 216 out and hope I have the knowledge to finish with all of your help.

I am boxing the frame, I saw someone that makes the metal to weld in I am researching that now.

 

You didn't mention it but you will have to replace the rear end and rear suspension also. While you are at it, do yourself a favor and replace the front end too. Upgrade to a MII.

 

I planned on using the MII front end and coil ivers in the rear. Then while researching I founf I can still use the MII that is bagged. I know the bagged trucks sell for more but I have never rode in a vehicle that was bagged so now I am unsure.
even with all these choices I am not overwhelmed. Its awesome. I just hope I can get enough info back from you all to help make decisions.
I found a company that I can order the steel plates from to box the frame rails. They were $500 which seemed very high but I couldn't find them anywear and I do not have a plasma cutter.

Any recomendations on front end, rear ends, and suspension choices either bagged or not please tell me.
​​​​​​​thanks again

 

To keep the cost down go with a Weld It series front crossmember, regular coil springs and tubular A arms, '88 T'bird power rack (non-sport) and of course 11 inch GM disc brakes. For the rear you can keep the trailing arm setup, find a rear end to fit and has at least 3.5:1 gears (posi) or numerically higher. Use either air bags or coil springs on the rear. I think your frame is the GM "top hat" design that does not need boxing but should have a plate scabbed into the front from the firewall back AT LEAST. You can make your own boxing plates without a plasma cutter. Get a 4" angle grinder and some cut off wheels at Lowes. Find a steel supplies in your area and get some 3/16" plate and cut them out yourself. A word of caution, the 4" cutoff wheel is the most DANGEROUS tool you will ever own. Wear protection and never stand in line with the wheel rotation because if it breaks the broken wheel will go thru just about anything.

 

Or, if you were prepared to pay $500 for boxing plates, instead buy yourself a $500 plasma cutter and you'll always have it. It will come in handy for the rest of the project. It won't be the best machine on the market, but for a hobbiest who wont use it much it should last for a long time. Just a thought. .....

 

You could buy an acetylene torch for a fraction of what the plasma cutter costs. A torch has 1001 other uses.

But like said above cut off wheels will make quick work of things. For heavy plate like that get an old 7 1/4 inch circular saw and put an abrasive cut off wheel in it. I use a cheap Sears garage sale saw. The cut off wheels are available at all the home stores.