54 Super/ 55 Roadmaster interchange

[Super54]

I have a '54 Super that I'm working on putting back on the road and a '55 Roadmaster that is so far gone I'm using it for parts. How much will interchange between the two cars? They are both 322 engines, the '55 has a 4 bbl intake though. Can I swap the 4bbl to my '54? What about brakes? I understand that the Roadmaster has larger front brakes? Will those swap onto my '54?

[58buickspecial]

dont quote me but I would think the engines would be dam near identical. As far as brakes go, the spindles may intercage(from the ball joints) better check on the sizes though. Best thing is to get a hold of the mechanics manuals for both cars. The one for my 58 was very specific for all the parts and theyre dimensions, even down to the part #s, I've seen manuals like mine on ebay, for 20 bucks or so, worth it for the information that might make the diff of driving it 2 months from now instead of a year.

[Super54]

I actually have manuals for both of them. I just never thought of checking them. :Dou: So used to modern Haynes manuals that don't really go into specifics.

I bought the '55 first and ordered a manual before I even picked it up, but got it home and decided the rust was just way too out of control to try to fix. Everything, frame included, on the bottom half of the car is about gone.

The '54 is pretty rusty in its own right but the frame is solid and it is mostly solid mechanically. It would be on the road now if the gas tank wasn't shot out. But I should have that under control by next week.

[Gary Bohannon]

I put 55 Roadmaster brakes on my 54 Special. I think I just used the backing plates with the drums,
The 55 Roadmaster engines have considerably more power I guarantee. I can't think of any problems with the engine swap. I May have used the 55 exhaust manifolds, and I removed the exhaust heatriser butterfly and pluged the holes. Exhaust putty may work or find 2 short bolts that will hold without splitting the manifold.
The 55 has more compression and a much better cam. These engines used to go into old dirt stock cars (30's coupes) and ran with the best running 6000 rpm on the straightaway bone stock. They all have dual valve springs.

In 1955, Buick beat the new Chrysler 300 HEMI and was protested at Daytona 500. The only thing they could find to disqualify it was grind marks on the pushrods. The mechanic worked all night to install a thiner head gasket which had been approved but obviously could not go to the store to buy shorter pushrods in the middle of the night. He had no other choice since Buicks have no valve adjustment nut or threads. He did a masterful job of shaping them, but NASCAR said they had to be store bought or factory adjustable. Actually the top NASCAR official wanted the Chrysler to win as the Chrysler company had spent fortunes on promotions and Nascar would become asociated with the massive publicity if Chrysler won the race. This disgrace is now part of NASCAR history. Try www.fireballrobertsm1.com/

[Super54]

I physically checked the brakes and they will swap but is the extra 1/4" of material worth it?

I didn't realize that the '55 motor was more powerful. I was planning on just swapping the intakes but if the motor is different maybe I'll hold off and think about doing that down the line.

Right now I'm more worried about getting my new gas tank in so it will go and fixing the brakes so it won't go. :)

[Airy Cat]

If you are going to just use the '55 Roady for parts, I'd like to buy whatever you don't use. Especially the front brake backing plates; I have the drums already. svwright@sti.net

[Gary Bohannon]

Bigger is better on any drum brakes, especially for high speed hard braking. I've had them fade a few times and it is scarry. Hit the brakes hard at 90 and loose them at 50-60..oh ****!!!
Buy some good high performance linnings and that will help.

The 55 engine has a LOT more power than the 54.
Gary B.

[TheDarkside]

I got a question....... Could a 455 engine fit into a 55 roadmaster? Or would it have to be modified to fit in there properly? Just curious. DS :Comp:

[Gary Bohannon]

It may be a big job. Some examples are:
1.The torque tube rear would have to be changed to a leaf spring type like the Olds used or a more expensive exotic 4 link, etc.
2.The steering box and shaft may not clear the exhaust manifold on a stock 455 which is wider than a nailhead.
3. The stock radiator is not the greatest.
4. The motor mounts are totally different and will need fabrication.
5. The X frame may need a hole cut in it for driver side exhaust clearance.
6. The floor mounted brake cylinder and pedal will block the rear exhaust manifold exit and pipe. A 56 Buick or custom firewall mounted brake assembly will be needed.
7. Drive shaft angles may require a LONG tail turbo 400 to be poked through the X frame hole for drive shaft clearance and to reduce the length of the drive shaft due to the long wheel base. Also cross member changes needed.
8. I'm sure there are brackets, wires, clearances and more to deal with.
I have no experence with this swap but had many Buicks with mods.

[TheDarkside]

It may be a big job. Some examples are:
1.The torque tube rear would have to be changed to a leaf spring type like the Olds used or a more expensive exotic 4 link, etc.
2.The steering box and shaft may not clear the exhaust manifold on a stock 455 which is wider than a nailhead.
3. The stock radiator is not the greatest.
4. The motor mounts are totally different and will need fabrication.
5. The X frame may need a hole cut in it for driver side exhaust clearance.
6. The floor mounted brake cylinder and pedal will block the rear exhaust manifold exit and pipe. A 56 Buick or custom firewall mounted brake assembly will be needed.
7. Drive shaft angles may require a LONG tail turbo 400 to be poked through the X frame hole for drive shaft clearance and to reduce the length of the drive shaft due to the long wheel base. Also cross member changes needed.
8. I'm sure there are brackets, wires, clearances and more to deal with.
I have no experence with this swap but had many Buicks with mods.


Damn that sounds like a lot of work to do :Dou: . Maybe it would be better to keep it stock or try to get a slightly bigger more powerful nailhead instead. What's your opinion on that??? Hope you don't mind the questions.

[Mister T]

I got a question....... Could a 455 engine fit into a 55 roadmaster? Or would it have to be modified to fit in there properly? Just curious. DS :Comp:
If I recall correctly, there was someone here who dropped an early or mid 50's Buick onto a mid to late 70's rolling chassis over a year ago. Darned if I can remember who it was though. :Do No:

[Gary Bohannon]

The 401-425 engines would involve much the same work as the 455 mentioned previously but the narrower nailhead would clear the steering and other side to side stuff better.
The nailhead would retain the same position on the oil filter,distributor, generater,etc.,simplifying some of the wireing and clearance problems.
If you chose a nailhead, use only an engine that came with, or still has, a turbo 400 trans or there will be serious issues with flywheel to crankshaft and bellhousing pattern problems. They changed in 57 and again in 64 USE the 64-65-66 engines (401-425) ONLY. The 66 with quadrajet carb is best performer.
For now, I would super tune the 55 engine and see that the switch pitch in the old Dynaflow is working and have fun with it. Some Dynaflows did not stall up in low so you may experiment some. I liked leaving them drive and flooring it, but I mostly used factory stick trannys with 4 barrel 56 engines.
The only engines that fit straight in your Buick is 53-56.The 55 four barrel eng had 235 HP and the 56 had 255 HP. Two barrel models were less and stick shift models were even lower on compression and power.