Just dragged home a '74 model 400 Pontiac engine to install in the '55 Chieftain. Anyone have pics of fabricated motor mounts for such a swap? I' ll probably put a Turbo 400 behind it. Any help will be greatly appreciated.
More to it than that. Steering box is always in the way. Hurst makes a front mount that is fairly easy. You can buy a rear crossmember or make one. Seems I saw a front mount for sale here recently.
Your going from a engine front mount and two rear side bellhousing mounts . to two engine sideblock mounts and a single rear trans tailhousing mount. Now any engine from 55 thru 60 would be a bolt in.
Finding that engine locally is another thing. I gave up trying to find a '55-'60 Pontiac passenger vehicle engine or a '55-'59 GMC truck Pontiac engine. As I now have this engine , '74 model 400, let's talk mounting it in a '55 Chieftain. I don't have the transmission for it yet, but have access to a Turbo 400. I assume it will need a cradle type fabrication to mount the side mount engine to the front center on the frame and probably the stock '55 front rubber mount. I'm up for suggestions and brain storming. Let's try to keep it simple, as I am a parts changer, not a mechanic.
I would pull the entire front cap. it will save time in the long run. I would get my transmission and mount it to the engine. and get it positioned in the car where it needs to be located. Then build and install my trans tail mount rear crossmember first. Then fab up the two side engine mounts. You make templates from stiff cardboard. transfer that to steel. You will need torches , a grinder and a welder. I looked for a few years for a 59 or 60 Pontiac 389 engine. And Never bought even one vehicle in 2018. And on New Years Day this year. Went to a estate auction. And I bought a 56 GMC 316 mill with bell flywheel starter ,clutch and three speed trans.And a complete 60 Pontiac Catalina 4 door with the desired 389 engine. In the past I have owned two 55 Pontiac Htps. both had 287 engines and 4 speed hydros. I had a 63 389 engine & trans. and looked to see how much work it would be to swap and decided to leave them stock. Your swap is never going to be a bolt in or something you can buy mounts or a kit to make it work. So if you cannot do the necessary fabbing and cant find someone who can. Your swap isn't feasible.
If you tried to use the stock 55 front mount. you would need to change the entire front timing cover water pump pulleys ect. and convert your 400 to reverse cooling.
Old wolf is correct that this is never a bolt in job. There aren't motor mounts you can just buy and use. While you can buy a rear crossmember you are going to have to modify it. I built my own. My application is different from yours as mine is far more modified than a simple swap but you can see the rear mount we made. You can also see the front mount we made for the side motor mounts. The problem with all 55-57 Pontiac swaps is steering box clearance. I think you can still use the front dump manifold.
If you use a 60 Pontiac timing cover you don't have to do reverse cooling. It has the provision for the front mounting like the 55-58 Pontiacs. If that is any help.
as was said: if you use any engine other than a 55-60 Pontiac engine, you'll have to have motor mount brackets welded to the frame. You'll also need to fab up a transmission cross member as 55-57 Pontiacs didn't use one. It's not a bolt-in swap. One of my 57 tudors used a '67-400-4 speed [bought it that way] but I didn't take photos of the brackets.
Like I said I do have a 60 -389 and a 56 GMC 316. and a locked up Pontiac 316. Hard to find but they do exist. Possibly you could get on Facebook and the Hamb classifieds& other places and advertise to trade the 400 for a 55 thru 60 engine that would be a bolt in swap. I already got a 69 400 and some 350,s already.
Thanks Wvenfield, that's a good photo of what I am looking forward to doing. I always pull the front clip off of a car to do an engine swap, far easier than trying to shoe horn it in otherwise.I knew it wouldn't be a drop-in procedure, but I figured I could get some good advise from those who have trod this path before me.
What transmissions will bolt up to this 400? Anything from the '50s? And will the 1960 389 timing cover fit without major modifications? Just trying to find the simple solution for an install and motor mounts. I'm not a welder/fabricator.
since your not a welder & fabricator your desired swap isn't feasible. No early trans that have the rear side mounts will fit your engine. A 60 front mount and a newer tailshaft rear mount simply put is marginal at best.
Right, there is NO easy way to do this. Easy as in bolt in. Anything you do is going to take some fabrication.
I now have a TH400 to mount to the 400ci engine and a friend who does weld and fabricate has agreed to jump on board, so let's see what happens. I do appreciate all the input, keep the ideas coming!
I've got a '58 370 with tri power if that would be something you might want to purchase. Sent from my SM-G925V using The H.A.M.B. mobile app
Just remember, you need three points of mounting, you cannot mount the engine with the early front mount and the late model transmission with only a tail shaft mount. The engine or the transmission needs to have side mounts. I have seen a '55 Chevy truck with a 455 Pontiac, he used the Ran Air exhaust manifolds facing backwards, very clever way of getting around the steering box and still have good exhaust manifolds. The good thing about your '73 block is it has multiple engine mounting holes on each side. You might consider a mid plate like race cars use, heavy aluminum plate between the transmission and block. This would give you your three points of mounting.
I had a 57 Chieftain. We built the mounts and crossmember. https://www.jalopyjournal.com/forum/threads/57-pontiac-drag-car-build.1082968/
Son and I put a 455 Olds with Turbo 400 into his 55 Olds. This is the link to his build. Most of the pics are gone but the early ones showing what we did for engine mounts are still there and may help you. If you need more pics contact him or me . https://www.jalopyjournal.com/forum...mobile-dual-mc-brake-and-booster-swap.991789/
Rusty Heaps My 60 Pontiac has a 1965 389 with a Buick Grand National 2004R transmission. That would bolt to your 400. Can cruise Interstates at 80 MPH all day long without breaking a sweat, RPM's just over 2000.
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