My 72 has your basic L-48 and it is time to do something to it.

I was thinking of a Big block or maybe a Small block 427?

What do you guys think? :chevy

 

The bulk of your parts needed (besides the BB)are all the pulleys, brackets, radiator, fan shroud, etc. Do a search on "bence13_33" and you'll finds LOTS of info on making the swap.

I'd go for it, but then again I'm biased. :D

 

I'd go with the big block, and in fact I'm in the middle of it right now. headers were about $200 (heddman), I just got a new pan cause the one on my truck engine wouldn't fit, that was $100, big and small blocks use the same mount geometry so it will physically bolt into the car with ease, but like Corey said the cost is in all the accessories, many of which are vette specific. The engine came with pulleys for me, and alternator brackets as well as PS brackets which I can't use. My dad and I are planning to fab up PS brackets, and use the truck alternator brackets if we can. Ask me what I think when it's all said and done. :chevy

 

Thanks guys...
Wish me luck I have to talk the wife into it now :D

 

Just tell her IF you ever decide to sell, it will bring more money. :thumbs:

 

To install a Big block you must have a big block hood or the hood won't close. Even with a stock BB hood(not the high rise L88) you still must use a Corvette specific low rise BB intake manifold and a Q-jet carb WITH the drop base air cleaner or that hood won't close either. Not applicable on 73 and newer

 

Yeah, I forgot about the hood. If you choose just the BB/LT-1 hood, then you got to stick with a low rise manifold and give up some HP. Let's not forget the new headers/exhaust manifold. Most likely you'll want to upgrade your exhaust to a 2.5 in at least. It ain't cheap. If you go the crate route, you'll spend $4,500-$7,000 just on the engine. :eek:

BUUUUUTTTT! There's nothing like the torque of a BB!

 

I just got done with my conversion. Believe it or not, the small block hood will close if you use a Torker II intake and drop top air cleaner. I can't believe it either. It's very tight, but it closes. This is just temporary until I get my big block hood.

It's a more difficult swap than a big inch small block or a supercharged small block. I believe you could have a strong supercharged small block making probably almost the same power as a moderately built big block, and have perhaps less investment as long as you don't go too crazy.

For a big block:
The suspension must be upgraded. You need to get heavy duty springs. While you're at it, might as well go for new suspension bushings and all 4 shocks too. Don't half build something, only to revisit the issue later.

The cooling system must be upgraded. But rather than buying an expensive big block radiator support and then a larger BB radiator, I went custom, and I'm glad I did. I had a 5-core radiator made with brackets welded on so that I could remove the radiator support and bolt the radiator directly to the sides of the engine bay, in the same holes the radiator support bolts through. My cost was around $500. But you're probably looking at closer to $700 doing it the traditional (and less efficient) way. Depends on how OEM you want to go.

The brackets are all different. I got the '68 BBC brackets, which mount the alternator above the PS pump on the driver's side. This is a hassle. I'd suggest going to the '69 and up BBC brackets, which moves the alternator to the passenger side. I also customized the brackets to increase redundancy in the accessory belts. I didn't like the PS pump driving the alternator and nothing else. A lot of trial and error, but it works great.

The pulleys should be upgraded. I strongly recommend against saving money here and getting the "stock" pulleys with the pretty chrome plating. These are made in China and they don't fit! Instead, order an excellent quality set of billet aluminum pulleys, made here. They're incomparably better, and allows you to convert to a single serpentine belt system if you wish.

I did not gain very much weight. I took my '68 convertible to Bandemere and weighed the car with a full tank of gas, and it weighed a mere 3325 pounds. Plan on at least 100 pounds lighter with a small block.

What I recommend for fit, finish, and ease of installation, is the Vortech centrifugal supercharger for carburetors system, which encloses the carb in a very nice looking billet aluminum box. You can build your own 350 up. It's already low enough compression. Just beef up the bottom end. You can use your rods, but I might have them shot peened and polished, and definitely use the best ARP rod bolts, and fasteners throughout the engine.
Forged pistons, baby. Nothing less will do!
And you want to upgrade the heads. I'd suggest putting some money into an excellent set of aluminum heads. But for a 350, keep your valves 2.02/1.60 for a street engine. You want to keep your torque up until that supercharger takes over.

You could probably get away with your stock suspension and drivetrain if you rebuild your 350 and supercharge it. So you'll save a few thou there. You'll still need a better radiator maybe, but you could try it and see. At least you won't need a whole new radiator support.

And the big bonus is that with the small block, you'll still be able to afford the gas as a daily driver. With the big block, it runs great, but gas mileage is noticeably much worse.

If I had it to do over again, I probably would've built a 400 into a long rod 377 and twin turbocharged and intercooled it. But that's a lot more exotic than a supercharged 350, not to mention a lot more expensive. Just ask Monty.

Yeah, if you keep it reasonable, you'll have a 500 hp/500 lb-ft small block that'll run with just about anything, for probably not much more than 5 or 6 grand. And that's a good 3 to 4 grand less than a big block conversion done right.

Something to think about. :rofl:


[Modified by Bearcat, 8:18 PM 6/18/2003]

 

Nice read, thx Bearcat.