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I bought a stock 454 today out of a 70s dually. What all is involved in a big block swap into a 55? Is there going to be oil pan clearance trouble? Will stock exhaust manifolds work with factory steering box? When I bought the car, it had a new set of side motor mounts still in the box.Will they work on a 454? I am wanting to get the car running and moveable, so budget is tight as to I have to redo brakes and fuel system also.Is there any such thing as INEXPENSIVE headers for a 55 with a 454? I have had a few 55s in the past but never a big block.Any info would be GREATLY appreciated. Dan
 

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I can't be of any specific help answering your questions as I have never put a BBC in any of the Tri-5's I've owned.I'm thinking another area of concern that you haven't mentioned is the radiator location....Seems to me it would serve you well to locate it to the 6-cyl position.You may also need to go to a short water pump.Sorry I couldn't be more help.....I do wish you good luck with your adventure.I am wanting to install a BBC in my truck so I'll be watching this thread for some helpfull advice....I hope!
 

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I can't remember about oil pan clearance, but I do remember that it's important to use the side mount/crossmember trans mount and move the engine at least 3/4 inch forward to allow for dist./firewall clearance. As Late55 stated radiator needs to be in the 6cyl position unless you are going to an aftermarket rad and fabricate your own braces. Also attention needs to be directed toward steering and header clearance. I'm not and expert by know means, but I can remember some of these issues from a friend's swap back in '68.
Hope this helps, some of the other guys probably can give you much more.
 

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Big blocks and 55-57

It seems everyone has questions about big blocks into 55-57's.Mounts,headers,oil pans,ect.In the late 70's I put a 325H.P. 396 big block into my 56' 150 busines coupe. All I did was use a Hurst front saddle mount and their frame mounts, a set of Hedman Headers, and "massaged'' the firewall for clearence at the rear of the valve covers. Also had to dimple one header tube close to the steering box. Could'nt run tall valve covers though. Wanted to us roller rockers but could'nt use the required tall valve covers so wound up using Moroso's saddle rocker conversion that turned out to be F**d Boss 302 rockers I think. Used the stock V-8 bellhousing and clutch assembly and a Muncie 4-speed with Hurst shifter.Also used the stock rear and promptly broke the stock 3.55 gears. Slipped in a 5.38 positraction 3rd member and never had any more trouble and this was a street car.Later put in a race prepped aluminum Powerglide and 68 Camaro 12 bolt with 5.38 gears on a Moroso Brute Strenth positraction to bracket race the car.Had to really sand bag the car as it did'nt have a roll bar. Finally blew the motor completely apart and sold the car as I was building a front engined dragster. Wish I had that car still to this day. As it was a business coupe I called the car Strictly Business. The only problem with the swap to big block was that on full turn of the steering wheel the drag link would just "touch" the oil pan. I thought it was a straight forward and easy swap I did by myself and at the time I had limited tools, space, and experience. So my advice is to just do it and don't sweat the little things and keept it simple. Butch
 

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Hey Dan,
I just bought a 56 210 and i'm stuffing a 515ci BBC into it with a TH400. I haven't gotten to headers yet but there seems to be plenty of room for stock manifolds. i did have to do alot of work on the firewall to fit the valve covers. You should have plenty of room at the pan. I have a full race pan and had no problem there. But i am using a front mount motor plate. As far as cheap goes "The smaller the budget The longer the project"
 

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Figured I would join this club when I saw this post. I too have been looking long and hard for info about a big block swap. You would think there are hundreds, and there are, but where are they?
I just ripped out my 283 and th350 on Saturday, and get this - My wife of 20yrs actually guided the motor and trans out while I pulled and pushed!
I decided to just go for it. After so much reading, im done. So I'm orderin a zz454 gm with a tci 700r4. There seem to be many motor mounts but the best seem to be weld in types. Better lookin too! As for your headers, well, no such thing as cheap. You'll be buyin em twice, trust me. Do it right the first time. Sell somethin you dont need and get good ones. Patriot makes em that supposedly will clear most side mounts and the stock or 605 steering box. Williams classic in CA makes a real nice set, pricey, but after talkin w/him he says they go in nice. His mounts are nice too as he's done many.
It does have to go 3/4 forward and you cannot use tall valve covers. I am taking many photos along the way and will have a nice layout for future explanation. Im doin new steering, cntrl arms, bushings, springs and all while Im in there. Gonna re-wire the whole thing under the hood, paint it and drop it in! Im sure I will be asking many questions here too! Good luck with your build!

Phil.
 

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BBC in '55

I pulled the 350 and installed a 454/Muncie in my '55 Nomad using the stock bell housing mounts and fabricating some adapters for the front mounts. I installed the engine & bell housing to the stock rear mounts to position the engine. I centered the front of the engine, blocked it to the front crossmember to load the suspension (to check level at carb) and bolted the stock front mounts into the original 6 cyl mounting holes in the frame. I then made some adapter plates between the threaded holes in the front of the engine to the stock metal V8 mounts. Used 3/4" thick plates approx 2" wide by 3" tall and drilled to match the holes in the front of the engine. Then counterbored with a bigger drill bit so a socket head capscrew could be used to secure the plates to the engine and not protrude past the surface of the adapter plate. I then match marked the hole positions for the stock metal mounts. Drilled and tapped those holes for 3/8" bolts. The harmonic balancer just clears the crossmember. The HEI clears the firewall with no denting. The clutch linkage aligns because the stock system bolts to the bell housing. Valve covers clear everything, although on the passenger side the battery box will probably have to be removed to remove the valve cover. I bought a set of headers for a BBC into a '55 and they cleared with no denting. I do not remember what brand but I think I got them from Summit. #5 tube is very close to the steering box and probably should be dimpled slightly. Steering clears stock pan. Stock fuel pump clears, but had to bend inlet fitting up just enough to get rubber hose on.

I did this about 15 years ago----before I knew about all the problems associated with this engine swap.
 

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Big Block Swap

I've been reading replies to your post with great interest. The car I just bought had a 454 with a turbo 400 sitting in it when I got it. I say "sitting" because someone had started the conversion and never finished it. I have bought the weld in motor mount (3/4in forward) and transmission crossmember kit and am working on it now. To say it's tight would be an understatement!! It had a Moroso oil pan with a notch out in the front for the steering linkage, but I'm still trying to get it to clear everything or come as close as I can before I weld anything. Let me know how you are coming on yours because I will definitely need help.
George
55 BelAir 2dr HT
 
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I bought a stock 454 today out of a 70s dually. What all is involved in a big block swap into a 55? Is there going to be oil pan clearance trouble? Will stock exhaust manifolds work with factory steering box? When I bought the car, it had a new set of side motor mounts still in the box.Will they work on a 454? I am wanting to get the car running and moveable, so budget is tight as to I have to redo brakes and fuel system also.Is there any such thing as INEXPENSIVE headers for a 55 with a 454? I have had a few 55s in the past but never a big block.Any info would be GREATLY appreciated. Dan
Hafrod: I have taken the liberty of sending tech articles to you covering the installation of BB in the tri5s via e-mail, hope they help.
Bob
 

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Big block Tech Articles

Hafrod: I have taken the liberty of sending tech articles to you covering the installation of BB in the tri5s via e-mail, hope they help.
Bob
Bob, How about sending those tech articles to me too if it wouldn't be too much trouble.
Thanks,
George
 

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Bob

Please post those tech articles here for everyone if it's ok, I know a lot of people would be interested, just please make sure to give the proper credit to the writers of the Tech Articles.

Thanks Otis
 

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56sedandelivery outlined exactly the same process I used to put my 454 in the delivery back in '81, of course back then there were not the fancy 'move forward' kits etc. that are out now so we just had to wing it. The Hurst mount system is still available new and is a very solid system but most seem to opt to move the engine forward so as not to dimple the firewall, however the way we did it 'back then' allowed us to use the stock bellousing mounts and required no driveshaft modifications other than the yoke. Couldn't get much more simple and my mount held a 396 into a '56 before the '57. I don't know about the fit of stock manifolds with the engine moved forward but they hit the steering box in the stock engine position, I did see one guy with a '56 that shifted his engine to the right to gain clearance with stock manifolds. And for those that need to dimple the firewall the best tool for this is an old trailer ball that still has the rounded top attached to a metal bar for a handle, it makes a much more gradual 'dent' and is easier to get the desired result than a ball peen hammer.
 
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