how to swap big block (454) in a 1961 chevy apache

[BruceTheTruckingCat]

HI there I have been thinking about get some power in my truck and with the 307 small block its not worth it to upgrade it. so im thinking get a 454 big block from the junkyard and swap it in. so i was wondering if anyone else has done something like this before. and if they could give me some about advice about doing something like this
I also have a few questions that if you could answer would help
1) How easy does it fit I have read some things that its a blot in and other people say you have to cut up the firewall.
2) for cooling I'm guessing that the 2 core radiator i have now will have to upgraded but i dont what to upgrade it to.
3) for transmission i was thinking a nv4500 would be a good pick. any thoughts on that.
4) if i get a 454 im guessing that its going to be from the 80's to the 90' so it going going to have bunch of emissions BS. So I think I would get a dual plane intake, a Holley 4 barrel, and a good pair of headers. Any thoughts on the HP

['63GENIII]

I think that the BB should bolt up in place of the SB that you have BUT.. I would move the engine forward if at all possible. Mine is in the original position and for years I swore that the firewall had not been "massaged". I have recently discovered that the firewall had in fact been hammered or shaped at some point for the 396 that was in it. It was always a big deal to get the passenger side valve cover off but do able. Now with the 454, (1997 Gen6), I dread pulling the passenger side VC. Move it forward if you can.

You will need a big radiator. I can't speak to the aluminum ones as I don't have one yet. I have a 4 core brass. Does well. Constant 185.

NV 4500 is a great transmission. You could use the stock belhousing with the external slave cylinder. Id get the later '95 up as it has more streetable gear ratios than the pre 95 transmissions.

[urmyboyblue]

I have a BBC in my 65. I had to clearance the firewall some with a hammer, but how much I don't remember. You will probably need a bigger radiator. I use a universal aluminum version from Summit Racing. No idea on the transmission. Without a cam change and probably some head work, you won't get much more than 300HP from an 80's or 90's 454. That time frame covers the Mark 4, Gen 5 and Gen 6 era, so there are differences in all three. Do some research in any engine you find before you buy- not all parts interchange on the three generations of BBC and I think that the Gen 5 has a limited aftermarket support due to its differences. BBC's are hard to find in junk yards around here.

[duallydude63]

i put a bbc in mine(63) & moved the engine mounts 2in forward jst 2 make sure i would have valve cover wouldnt rub !!