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Okay here's what I'm facing... I have a 1965 Chevy 4x4 1/2 ton that had the original 283 in it... I want to pull the 283 and swap in a 350 that is out of a 79 Chevy 2wd 3/4 ton... the only problem is the motor mounts arent the same... the 65 doesn't have the cross support like the 79 does... help!! where do I need to go from here?

Thanks.

Hy bowtie65, if you take the mounts that were on the 283 and install them on the 350 everything should drop right into place, hope that helps.

The 283 probably has a set of mounts that bolt to the front of the block beside the harmonic balancer, right? The 350 block has the same bolt holes drilled/tapped, so your 65 mounts will bolt right on. Just remove the side mounts on the 350, and re-use the 65 mounting system.
Jerry

I thought by 65 the V8 was using the side mounts - maybe the "missing" cross support is the trans mount, for which the aftermarket ones might do, except 4x4 might be the difference

Bill

If your 350 has the large damper you have to cut some metal out of the brackets.

Does it make a difference if the 350 came from a 2wd instead of a 4x4? Or is there an adapter I need to be looking for to make this work. Also, I noticed the 283 motor mounts appear to be riveted in... what's the best way to get these off?

Thanks.

externally the SBC's should be the same between your 283 and 350. And no, to my knowledge there is no difference on the engine if it came out of a 4x4 or 4x2. There are 4-bolt engines and 2-bolt engines, both with the same casting patterns.

Please forgive my ignorance here, but what exactly must I do to make this work... the 65 does not have the cross support that the 79 does, therefore the 350 will not just "bolt right up". Do I have to use the motor mounts off the 283... that are riveted on... in order to fit the 350 in? If so, what's the best and safest way to remove the rivets? Thanks.

you need to elaborate a bit about this 'cross member', and where the rivets are on the 283 - the 283 and 350 blocks are enough the same, you should be able to put the 350 right in where the 283 was, nothing is riveted to either engine

the only cross member that might be required would be for the trans, and there will no doubt be a difference between a 4x4 and a 2wheeler, but that doesn't affect bolting the 350 to the original 4x4 trans

is the 283 mounted at the front? if so you can unbolt those mounts from the 283, and bolt them onto the front of the 350, should only be the brackets on the frame that are riveted .... if it's mounted at the sides, the mounts will still bolt to the block, and the mounts themselves will be bolted to a mounting bracket .... GM didn't rivet engines in

got pictures?

Bill

Red 58 I will get a few pics first thing in the morning and post here... I guess then the main issue I am running into is the brackets... I will look things over more closely when taking the pics and find out what I am working with. All I know is the truck the 350 came out of (79 3/4 ton 2wd) has a cross support that the bottom of the motor mount bracket bolted to... and the truck it's going into (65 1/2 ton 4wd) doesn't have ANY support there. I'll post more with the pics tomorrow.

Thanks

Since 1955 when Chevrolet put the 265 engine in, there has NEVER been a riveted-on motor mount bracket. There are two brackets BOLTED to the front of your 283, right beside the crankshaft pulley. The bolts have 9/16" heads. Unbolt them, and bolt them onto the 350 in exactly the same locations. The holes are there, as they have been on every Chevy V-8 that's ever been produced. One of the holes on the passenger's side will have a short bolt in it to prevent oil leaks from the fuel pump pushrod hole. Take that one out and replace it with one of the mount bracket bolts. If your 350 has a large-diameter harmonic balancer, it will be necessary to trim the brackets for clerarance, or just substitute the 283 harmonic balancer for the one on the 350. Either one will work.

At the back, the bellhousing for the 283 will be a direct bolt-in swap onto the 350.

Good luck!
Jerry

Thanks for all the help guys. First thing in the morning I plan on looking things over alittle closer... all along I should have been saying brackets instead of motor mounts.. that is the difference I believe.


Thanks again.

Hotrod Lincoln: If someone has changed bolts shouldn't he be careful that the bolt, that goes in where the hole is for the fuel pump rod, is not a long one as it could go in far enough to lock the fuel pump push rod? Its been a while since I looked at one but that thought did come to mine.

Correct me if I'm wrong.....

yer right Alvin, one hole requires a shorter bolt, but what he said [using the bolts that were in the 283] should take care of that

Bill

YOUR right Red58...as usual:) I guess I was just being picky
BECAUSE I currently have an engine that the previous owner had used a electric fuel pump and if I had used the bolt he had stuck in that hole, I would have locked the push rod. They had a looong bolt stuck in it so "if by chance" bowtie65 had a similar situation using the same bolt could be a problem.

I know this is overkill but I have learned soooo many lessons the hard way, and still do, that I just want to help anyone I can from more heartaches than he already may have.