The Stovebolt Site Forums The Shop Area Engine Shop 454 into 1958

So I potentially got a line on a 454 to replace my tired 235. I've read lots of the old posts about this swap, but still have some questions.

What is the weight difference between a 454 and a 235?

Can I keep my original steering box with the stock 454 exhaust manifold or do I need to get some fancy ($$$) headers?

Thanks for any answers and let me know of anything else I might have missed!

60 pounds - prolly need the headers, most go to power steer with the box mounted outside the rail and/or a clip .... you missed fitting it to the firewall, or I should say fitting the firewall to it

Bill

Is it impossible to use the stock steering box? or do many people just choose not to use it? Do you have to offset the engine to use it?

Fitting the firewall to the engine... Sounds like some space needs to be generated to allow valve covers? How much "fitting" are we talking about?

can't give ya specifics, jha, cuz not being into BB's I haven't paid attention, but it'll be tight everywhere - a buddy put a 427 in his 55 and did headers and a deeper firewall center insert - stock steering tho

Bill

I have a big block in my 55 Cameo. I did the swap back in 1970, but remember the biggest issues.
Exhaust, The stock manifold will not clear the steering box and you will have to get headers for a big block into Chevelle or, if you can still find them, into 55-57 Chev. You will have to modify the pipes on cylinders 3 and 4 to clear the stock steering box. That is what I did and I was able to keep the lengths of the primaries the same. You can mount a Saginaw box forward, and that solves this problem but causes others such as drag link and steering arm.
There are two ways of mounting the engine, using the newer side mounts or the older stock truck mounts.
I used the classic early Chevy mounts, the front mounts will be in the 6 cylinder pads, the rear crossmember can be used, with no modification, if it is a standard tranny. If you are swapping in a Turbo 400 or 350, you will need to make a rear mount for the transmission. You will also ned to make some snubbers that take the weight of the engine at the original transmission mounts. This provides stability and supports the engine in the middle. ( It might sound crazy, but it has worked for me for the last 37 years. ) I used the stock rad and because I run synthetic oil, I have never had a cooling problem.
I am using the stock floor mounted pedals. when I had the 4 speed installed, I was easily able to modify the stock arrangement to work properly with the clutch.
I have made so many changes to the driveline, that I can't remember whether or not you will have to shorten the drive shaft. If I remember correctly, I don't think so. If you run a Turbo 400, you will either have to find a front universal to mount the large yoke on the tranny to the small yoke on the driveshaft. A trip to your local parts store will solve that problem. I went to Dana and found a small yoke that mounted on the back of the 400. A universal is less expensive and does the same job.
I have covered a lot here, if you have more questions, I'll do my best to answer them for you.
Bob

Regarding the firewall, the left cylinder bank will not clear the firewall and it will have to be dimpled to provide clearance. It isn't that big a problem, but it has to be done.
I don't think the HEI distributer will clear the firewall, but the older distributers, such as mine from a 67 engine, clear with no problem. It isn't the easiest to work on, but it would be no different than the location of the distributer of the small block V8. ( I had previously swapped 2 small blocks into these truck chassis )
Bob

Thanks all.

I've got a line on a 454 / SM465 in a big truck. Will likely buy the whole truck and part out the rest.

I'll possibly scavange the motor mounts from the donor. Hopefully the rear mount will work. I'm guessing I'll need a different drive shaft fabbed.

Note taken about the firewall and the distributor. I'd heard rumors of both, but nice to get a confirmation!

Thanks, and any more suggestions... Keep them coming.

I built the same set-up as BigBlockCameo back in the mid 70s. It is a very easy swap. I used the stock truck mounts with a Muncie 4 sp., headers with #3&4 tubes modified and a little hammer work on the fire wall. I use the stock rear axle with the 3.90 ratio. That truck was quick, real quick.

I ended up tearing up the stock 3.90 rear and a 57 chev posi rear, so I installed a 4.57 3/4 ton rear and had some 15 " rims welded onto the 8 bolt centers. I installed a Hono-Drive overdrive ( built to handle serious power ) , and it was a bullet proof screamer. Now that I am sedate and responsible, I am installing a 454 with aluminum heads and slightly lower compression because of the crappy gas.
Bob

2 words, Fenderwell headers!

So I've got the Eaton HO72 axle. I've got a 4.10 and 5.13 third member. I've been told these axles are nearly bullet proof, except for perhaps the axle shafts. However, if I twist one, I can buy larger, better alloy, 14 Bolt axle shafts that should withstand anything I throw at it.

I've got a detroit locker in it right now! Actually I think they called it a "No Slip" back in the day, but it's the same thing as a Detroit.

If I get this, it'll go in my 1 ton. I believe it's connected to a SM465 tranny, which is also fairly bullet proof. I'll keep that. I don't want a drag racer or a speed demon. I'm looking for a hauling machine.

That sounds like a good combination. When axles and differentials start to break, is when the traction is increases because of the addition of wider, stickier tires.
I never thought of using fenderwell headers because I live in an area where there is lots of rain in the winter and I didn't think the headers would last. I don't recall seeing any stainless headers being offered in the 70's. It wasn't a major problem cutting and welding the pipes for the 3rd and 4th cylinders because there is plenty of room to do a neat job. There is lots of room for the big block in the 55 to 59 engine compartment.
Bob