clayrwilliams

I have a 77 with a stock 350 with a th350 transmission and am thinking on throwing a 454 with a 400 transmission in. What all will i need to do this. Do I need a new rad or will my old one have the cooling capacity i'm after?

rave3c0

There is a sticky dedicated to big block swaps, i would read/search through it. I have a 79 with a 454 (previous owner mod), but i believe that your stock radiator doesn't have enough surface area/capacity to cool a BB. Those BBs run hot and it takes a lot to cool them. Consult the sticky tho.

clayrwilliams

sticky?

rave3c0

Oh buddy! Maybe you should check the FAQ section too. No worries tho. A sticky is a permanent thread or discussion that has been deemed important enough to be permanent, usually because everybody has asked the same question. Stickies are always at the top of the forum boards for easy access. The one i was referring to is at the top of this section "C3Tech/Performance" its the "who has actually swapped a LS1/LS2/LS6 in a C3".

rave3c0

BTW....im no expert either, but you will run into a lot of them on here.

HamadUP

Get yourself a Dewitt's aluminum radiator, you wont be sorry, I didnt

bashcraft

Try it first. There's a good chance the rad you have now will be fine.

7T1vette

The stock rad may be adequate if you don't run 'hard' for an extended period of time. It would be best if you put good electric fans (with a full-radiator shroud) on it to maximize its cooling capability. I don't think it will be enough if you leave the stock thermo fan and shroud on it. I would also recommend that you go to a more modern tranny (ie, 700R) with overdrive and lockup clutch built into it. That will save a lot of [unnecessary] heat buildup at highway speeds. Since the engine and tranny are out, it's the perfect time to make that change.

auavette

I do have a De Witts aluminum radiator with dual fan set up on my blown 496(8-71) that resides in a 76 vette.

bashcraft

I still have the stock '69 smallblock radiator and clutch fan cooling my ZZ502. No issues in the last 3 years.

calvette 11

I changed my 76 over to a big block.You will need to change the cooling
system.I use a be cool radiator and their dual electric fans.The one
for the a/t is 669.The fans are about 300.00.I got mine at summit.I will keep you aroung 180 to 190.Don't forget you will need a short water pump.I use the edelbrock about.169.00

bashcraft

Not always. A lot depends on how you drive the car. If you're going to be beating on it all the time you'll probably need something better (plus a friend at the police department), but with normal driving and the occasional short blasts, the stock components will be fine.

HamadUP

It also depends on where you live and whether you'll need A/C or not.

hugie82

My 74 had used a stock 4 core rad. from a BB vette and flex o lite dual pusher fans. That cooled a 427 with 11.5 to 1 comp.

l88rocket

i would switch to a good electric fan and call it good

chevymans 77

no need to throw money at an issue you don't have yet.

there are members that are running a BB with the SB setup with no issues and others that have spent a lot of money to keep their BB cool.

start with what you have and work form there

Neal

mydejavooo

Ehhh.....I see where you are coming from....but I don't know that I personally ascribe to that philosophy, especially when you are dealing with big blocks. I'm absolutely positive that you are correct....there are plenty of fellers out there using the SB radiators, but why take the chance? I would feel more comfortable putting in a few hundred bucks now, than wait till the motor overheats and grenades itself...needing thousands of dollars later to correct. And I realize that for most, that will never happen, but I'm just being the devil's advocate here. At least by replacing the SB core with a factory BB core, you KNOW you are putting in there what the GM guys designed to be in there. If figure that those guys know a heck of a lot more about cooling and such than I ever will.

Sure...you could try it, especially since the stock radiator is free and ready to go...but I would definitely have a backup plan AND a temp gauge, just to be on the safe side. No sense loosing a cam and/or motor over a $300 radiator and fans. Good luck, whatever you decide to do!!

Deja

HamadUP

a SB radiator WILL work on any BB engine transplants, but you need to drive in cool days only, you need to avoid heavy traffic, and you cant have A/C. I agree with mydejavo, why take a chance? .. keeping you engine cool is not something that you want save few $$ from!

DaJesterMan

I also have a '77 but with a 427 in it. My stock radiator with the proper shroud and stock fan has always cooled well enough. I got stuck in stopped traffic on a 100 deg day in NYC and it stayed right at 190... so like was said above, no need to waste money unless a problem develops later... the stock radiators are great if they are working properly

bashcraft

What's you're definition of "cool days"? Mid 90's? I've driven my 502 with SB rad on 90+ degree days, in traffic and never had a problem. But I have a convertible so no need for AC.