I have a 1977 Chev 1/2 that I have redone, it currently has a 305 in it, I was given a 455 with tranny (70,000 miles on it), I have been told that I need to change the motor mounts, and the cross member to make it fit in the 77, just wondering if anyone has done this?
Thanks
Al

 

Hey Al, welcome to the site! I have a 1979 1/2 ton that was diesel powered from the factory. the Olds engine bolted right up to the frame pads used in the Diesel application. So I believe all you need are the correct metal pads to bolt to the crossmember. John

 

Welcome aboard

I'm watching the answers cause I may need to do this one day.

 

What are the possibilities of using T/A mounts? They are basically factory adapter mounts aren't they?

 

Well i just put an Olds 350 in my 77C10. If you can get the diesel mounts use them. Then just move the crossmember back and redrill the holes. But your gonna need to get a longer driveshaft if you have the stock th350 with 9" tailshaft. What i did was use a longtail 400 (thanks Jeremy) and driveshaft from a 95 chevy 4x4 1500 (thanks steve) then a 7" truck 400 yoke and cut an inch off of it. Or you can just have a custom driveshaft made lol. Its about $250-300.

 

This is great information. I am in need of a pickup, and now I can look for one with bad or no engine and put a 455 in it. Thats a happy thought and a win win situation. Watch out John you could have a run on 455 engines and transmissions with this information

 

Thanks for the info guys, great site here, I am debating whether or not to do this swap, Doesnt seem to be to tough (aka cutting torch, lol). Am looking at headers as well but there a tad pricey here in the Great White North, 1k or better which is insane!! If I do then theres the extra cost of several sets of new back tires, bahhhhhhhhhh, its only money!!! thanks again guys, Ill keep ya posted, and Im sure I will have a bunch of questions!
Al

 

Abram, welcome to CO. I would think that a pickup would have loads or room in the engine bay to transplant almost any engine into. I would bet you could find cheaper header here if someone had some.

 

Don't bother with the A body headers.
You will thank me later.

A body headers didn't work well at all, and we pulled them because it was burning up starters in the truck.

Maybe some Olds Omega headers would work better, but most people don't have cash laying around to try 5 different sets.

 

The 77-79 403 T/A mounts, the 76-79 Caddy Seville mounts, and the 1980-1990 Caddy Deville with Olds 307 mounts are all pretty much the same. These are metal brackets that bolt to the Olds block and fit the Chevy clamshell frame mounts. That should open your search options, as the 5.7 diesel truck mounts are getting hard to find.

 

Anybody have a set of frame mounts, Im having a hell of a time finding them here, I have the motor side mount but no frame side.

Thanks
Al

 

Frame side mounts for what? Again, the trucks put the rubber mounts on the frame and the metal brackets on the block. These frame side rubber mounts are available at any auto parts store. You need to use the metal block brackets noted above to mate an Olds motor to these rubber frame mounts.

 

Thanks Joe, found a set here this morning, This is yet another dumb question, but the oil pressure and temp sender. One is on the body of the water pump? and the oil pressure is kinda behind it on the intake? Can I convert these over to non electronic?
tks
AL

 

Just get a mechanical set. Sold at any autoparts store. Its best to see what your engine is doing, other then just a dummy light that says your F-ed. The oil pressure will hook up right next to the oil fill tube on the front of the block, and the temp will go on the intake in the front as well. I would also recommend using a brass line, not the plastic crap that comes with the guage. (they always leak)

 

The Chevy senders should screw right into the Olds motor. If you want to retain the stock gauges, simply use the original Chevy senders. If you want different mechanical gauges, use the senders that come with the gauges. This not an issue, you have lots of options.

 

Again! Thanks fellas! This helps a ton, more questions to come im sure!!!!
Al

 

OK! So im an idiot! Did some checking on this 455, Its a 403, should have checked before I bought a bunch of stuff for it. Dam! Back to the mount problem, 403s a small block so to my way of thinking it should not be as much work, I have picked up frame pads and motor brackets based on the 455 thought, I think the frame pads are ok, but the engine brackets are way to narrow. Boy do I feel stupid, sheeesh!!!!!!

 

OK the truck had a chevy engine in it. What you need are 77-79 T/A mounts (engine side) for a 403. This will allow you to drop the engine straight down on the existing frame mounts.
It wouldn't matter if you were installing a 403 or a 455. The lower part of the blocks have the same dimensions.

 

Thanks, got a set on their way this afternoon, Glad to hear its that easy!!!!
Al

 

Ok! So got the T/A engine side mounts, put em on, dropped the motor in place and its out by approx an inch or so on either side. I can get one side to line up good but the other side is out by a lot and if I lower or raise still no luck. Seems to be in the right spot as far as where the block should sit in relation to where the 305 sat, but the T/A mounts are not wide enough to make up the difference, maybe it would be easier to fab the mounts off the 305???

I dunno!!!
Al