The Stovebolt Site Forums The Shop Area Engine Shop 261 ci engine in a 1951 1/2 ton

I recently purchased a 1951 chavy 1/2 ton pickup. The engine that came in the truck is a 261ci from 2 ton truck between the 1958 to 1962 time frame. I would like to know if anyone has ever succesfully place a 261 ci engine in a 1/2 chevy. If they have is there any special things I should be aware of if I use the engine.

thanks

water pump shaft needs to be the short one (Pulley as well)

thanks for the info

If the truth be known, there are many trucks with updated 235s under the hood. 261s are harder to come by and most of the owners probably would have opted for a 261 if it was available.

not a 261 but i put a 292 in my 51 3104, it's close. a 292 has offset side mounts.

see my photos link below

Here's a guy that exploited squeezing power out of a 261 and then put it in his 1952 pickup after it came off the dyno:

http://www.selectric.org/55chevy/soup.html

There are a couple of options on what to do about the water pump and my favorite is the adapter plate method. Do a search for that and see what's best for you.

Hey I took a look at your truck with the 292 it looks very nice. thanks for your input.

Hey, that is some good reading. I wish all the prices of the work performed, and the parts used, were still the same today!

welcome to the bolt

51 being an AD truck may have some variations but i am putting a 261 in my 46 1/2 ton. check w/ the AD guys. in a 46 i am using a water pump adaptor plate, look for pre68dave on ebay, very resonable and a nice piece of machining. this lets you place the water pump of the 261 back in the original 216 height location to work through the radiator better. a 53-55 watr pump #3836084 will solve the pump shaft length question. you can also get an after matrket version of this pump from the major flaps. the 261 could be offset or front mounted. in my 46 i am using a 235 front mount that may or may not have to be redrilled to meet the front crossmember. locating the remote oil filter is also another consideration. as of now these are my main considerations.

search the engine section and use 261 as a key word and you will find a ton more info. here are some more places to look.

http://www.inliners.org/tech/261_build.htm
https://www.stovebolt.com/ubbthreads/ubbthreads.php?ubb=showflat&Number=491452#Post491452

hope this helped

big ed

Professor;
I have a '58 261 in my GMC half ton and it fits nicely. You can see pics of it in the albums on the link below. Bored .040, mild Patrick's cam, solid lifters, dual Carter/Webers under Hellings air filters, Offy intake, valve cover and side cover, Fenton dual exhaust with Patrick's dual stainless steel exhaust system and stainless steel gas and water line plumbing. Sucker kicks!

I've got a '62 261 in my '50 and it works nicely, you just have to deal with the water pump and mount the oil filter so it doesn't hit the steering box. I made my own short water pump, but if I was doing it again I'd use the adaptor plate to put a 216 water pump on it, I had to use an electric fan since a mechanical fan sits too low in relationship to the radiator compared to the 216.

I'm about to tear it out and go with a 302 GMC I'm building, though. The 261 was fine but the one I have is tired out and burning a quart of oil every 200 miles. The Jimmy motor has more cubes and a much better combustion chamber design.