1972 Big Block Swap Offical thread (pic heavy)
 

Figured i would just make 1 thread for all the updates.

Here is a little background - 1972 Corvette Roadster with nonmatching #s 350 and a M20 4 speed. Car was frame off restored in 2008 locally.

Have scoured the net and these forums for assistance on this swap - now while this has been done numerous times, the questions I searched for had varying answers.

I am humbly posting this hopefully as an all inclusive (for my car) should someone wish to have detailed specifics on this type of swap on this year and model Corvette.

I am installing a 454 big block.

So far I have ordered the following new parts:

-Auto Gear M22Z 4 speed
-Stinger Fiberglass L88 hood
- Rear wheel bearings (not related to the swap)
-New radiator support BBC
-New radiator mout and sealing kit BBC
-New BBC accessory brackets (alt, power steering)
-New BBC power steering pulley
-New Centerforce DF clutch

Still a TON more to order but I can only spend so much in a week lol.

Here are some pics below of before the work and the start of the swap.
https://cimg6.ibsrv.net/gimg/www.cor...1d00aeac81.jpghttps://cimg9.ibsrv.net/gimg/www.cor...c6458f793b.jpg

Now for some pics of parts and work:


https://cimg8.ibsrv.net/gimg/www.cor...3c0e19e30d.jpg
https://cimg2.ibsrv.net/gimg/www.cor...92590c58aa.jpg
https://cimg5.ibsrv.net/gimg/www.cor...e65910be5d.jpg
https://cimg2.ibsrv.net/gimg/www.cor...d2b1224f58.jpg
https://cimg0.ibsrv.net/gimg/www.cor...bfdc9940b9.jpg
23x17 radiator
https://cimg8.ibsrv.net/gimg/www.cor...db2f9c1dea.jpg
Wheel bearings in
https://cimg2.ibsrv.net/gimg/www.cor...1cdfbf4ac.jpeg
Brand new M22Z

If you are going to reuse your current alternator you will need a new pulley. Just found out as I was putting power steering on my brother's 68 427 car that the PS and non-PS cars have different alternator pulleys.

I had power steering before and will continue to have power steering. My pulleys will be set up for a short water pump using V belts - same as before?

Help me understand ? :)

BBC with a short water pump that have power steering use a different alternator pulley, because the alternator is driven off the power steering pulley not the crankshaft pulley as common on SBC. This places the BBC alternator pulley further forward. The pulley is this one.

https://cimg0.ibsrv.net/gimg/www.cor...e46dfa59fb.jpg


Will

Thank you for the visual! Is there an option to run it off the water pump; same as before? Or does it have to run off the power steering and there is no other way?

Anyone know where I can find a new chrome alt pulley?

Thanks again!

A standard double alt pulley running belt jn front groove will work for that setup. I betcha that pulley is not easy to find.

The correct factory style pulley is very easy to find and there as reproductions are currently mfgrd. All the Corvette specialty businesses sell them for $45 or so.

https://willcoxcorvette.com/corvette...r-pulley-66-72

Will

Trying to reuse your current pulley won’t work. It will put it about 1/2 a groove off. Just went through this with my brothers 68 big block car adding power steering to it where it originally didn’t have it. Picture for reference. You can see the rib and groove on the power steering pump pulley.

https://cimg2.ibsrv.net/gimg/www.cor...77d90659d.jpeg

https://cimg2.ibsrv.net/gimg/www.cor...9296996215.jpg
Before electric fan went in.
https://cimg6.ibsrv.net/gimg/www.cor...0c1b1367ad.jpg
After fan and spreader bar. Look at all that room!
Or you could go with a March serpentine belt set up. Looks cool, way more reliable in the long run.
I went that route and then changed out the fan to electric so I could add a spreader bar in there as room will be at a premium in the front of the motor once you tuck that 454 in there.
Pictures of my set up.

Your 454 belt configuration should look like this:

https://cimg1.ibsrv.net/gimg/www.cor...67fa818c52.jpg

For your chrome alternator pulley, you could try spacing out the alternator to line it up with the outer PS pulley. Here is an example of spacing out the alternator, but it still didn't quite line up like the correct pulley.

Wrong pulley:
https://cimg0.ibsrv.net/gimg/www.cor...f3e0cf1ced.jpg

Correct pulley:

https://cimg0.ibsrv.net/gimg/www.cor...65d347deb5.jpg

Thank you all!

Went ahead and ordered the BB pulley.

Is there a favorite brand of aftermarket pulleys that will work (non serpentine?) for the crank and water pump?

As far as the crank pulley goes its a 2 rib pulley. I don’t know how particular that deal is given the short style water pump the Vettes use. Might be a cheap date, or is as expensive or more so than the water pump pulley. Now as far as the water pump pulley goes, hold on for that little gem. See if you can find it used because the 3 rib pulley isn’t cheap. Somebody might know of a suitable substitute but not too many big blocks out there with a short style water pump.

https://www.corvettemods.com/C3-Corv...SABEgJP6PD_BwE

If you are thinking chrome I have no idea where to find that. Might need to to talk to a local motorcycle shop and see what kinda trouble you would be looking at.

This pic shows you all the stock type BB pulleys you will need if you want to go that way: They are all available in repro houses. Everything is specific to a BB w/ PS. You need them all, the alt and ps stuff. I'm in the middle of accumulating them myself. The PS pulley is only avail in cast iron and goes for around 120 by itself. The rest of it adds up because you need so many pieces. Maybe $400 for all of it.


https://cimg1.ibsrv.net/gimg/www.cor...67fa818c52.jpg

https://cimg9.ibsrv.net/gimg/www.cor...368020f7ad.jpg
https://cimg1.ibsrv.net/gimg/www.cor...df1f727c8c.jpg
Pics from Paragon

Thanks. I ordered all my brackets and pulleys from Bairs last week.

I was hoping i could run aftermarket billet pulleys on the crank and water pump and be ok? I would think I should be assuming I make sure they are for a short water pump as the rest of my pulleys and brackets are for short water pump.

I did have billet pulleys on my SBC and had no issues - certainly cheaper than OEM:thumbs:

Would this one work? https://www.ebay.com/itm/BB-Chevy-BB...cAAOSw8PJcVeUI

Just stick with the factory / repro pullies and you won’t have any problems. I did the swap you are going and got everything from Corvette Central. Takes the guess work out of it. You’ll spin the water pump the correct speed and won’t have issues with overheating. Be prepared to “tweak” the lower PS pump bracket to properly align the belts. It will take about 10 attempts. Lol...

Good luck on the build.

Wow....your flywheel was toast.......good thing you pulled the engine! What are you going to do with all of that cool small block stuff?

Jebby

Everything will be for sale I'm sure. Focus is getting the car on the road first. Then I'll list it all

Update
 

Good morning -

Here is an update: block is being cooked and prepped. Need to order a flywheel and water pump today.

New hood arrives Friday!
https://cimg7.ibsrv.net/gimg/www.cor...17bc45c75f.jpg