I have a 53 olds,I want to drop a 59 371 engine under the hood, but want to keep the 53 hydramatic...can anyone tell me what is involved?...I was told I have to bore out the end of the crankshaft to accept the trans.thanks

I believe 1949-56 303-324 engines are balanced differently than the 371-394 engines. By the way, I have a 371 J-2 manifold complete with original carbs, linkage and thermostat housing, is it worth anything?

Did you try to Google for information? I found this in 2 seconds.

The 394 engine crankshaft is externally balanced with the flywheel, as a matched set indexed to the crankshaft. The 56 324 is internally balanced on the crankshaft. To use the 56 Hydramatic, the balance value must be transferred from the 394 flywheel to the 56 flexplate.


Click to View Link-> Project: 394 engine into a 1956 Olds, by Dave Omstad

Geor,just curious why you would want to do such a thing...is it the availability of a motor? If you want more power ,you could put some # 10 heads from a '56 on it,a pair on ebay today going quite cheaply(so far).The '56 block can be bored out .060 easily so I'm told and hot rod parts are still available...just wondering.

I had a 59 371 in a 53 years ago but I used the 59 trans,yes the crank will need to be redrilled and the motors are ballanced different. The flywheels between the two motors are very different so a 53 flywheel will need to be balanced for the 59 motor but if I were to do it over again I would find a 55/56 324. The 59 motor is wider and the drivers side exhaust manifold dumps at the steering box making a exhaust hard to fit and no other manifolds will work on that motor except for headers,if you have power steering you might as well forget that swap as it will be a pain to get a pipe on the drivers side. Since I used the 59 trans I had to shorten a 59 crossmember and re drill the holes in the frame so the rear of the motor could be mounted,when I done the swap I had a complete 59 parts car that made it easier. Just find a 55/56 324 and everything will bolt in. Jeff

pete324rock.........I HAVE A 371 ENGINE THAT WAS REBUILT.... AND THOUGHT IT WOULD BE A EASY SWAP...MAYBE I should rethink this...Thanks

Good answers guys!

Thanks dep5...the link you mentioned had a lot of very useful info..I have surfed the internet and found a lot of useful information...but nothing that detailed a swap like that.I have a 303 which I am swapping for a 371..the link was swapping a 324 for a 394..I do not think there is much difference...Thanks again

junkyard jeff...I have a machine shop that will drill out the crankshaft and balance the flywheel...I will be using the 53 trans..so maybe If I use headers I will not have to many problems..The 371 has been bored out .030 over with a mild cam and a set of 400cfm dual quads and with a set of headers will help with the power..The car is a 53 super88 two door sedan..I like the idea of a little more horse power,but I am building it mainly for cruzin..Thanks

geor,I thing you are going down the wrong road but don't believe me,post the very same question here:
http://www.jalopyjournal.com/forum/forumdisplay.php?f=5
You may have to register to post,I don't recall,but there are some really wise rocketeers and the posts fly by pretty quick so may have to keep an eye for a response but for sure you'll get one.Lots of help as well and the archives (search) will give you lots of old olds perfomance tips you won't find elsewhere.You might want to get a catchier name as well..

If you use the 53 trans the swap will be easier due to both using different rear mount crossmembers,I wanted to use the 53 trans when I done mine but I did not know much about them back then and had no clue to where to have the crank drilled. I also had a 53 S88 2 door sedan and it ran real good with the 59 371,it would walk away from many cars with just a stock over 100,000 mile motor, You will need headers and I could not find anyone will ing to put duals on mine. Jeff

geor

I agree with pete324rock. Why not use the later hydramatic that fits the 371/394 and eliminate a few of the head aches? Since you seem to want a performance improvement and are not concerned about retaining the completely stock look of the 303, why not sell the 371 and get a 455 with a TH400 or R700 trans and have some real torque? That swap should have the same engine and trans mount fab problems and also require headers to clear steering, etc.