Thread: 377 Build

Tweet

Originally posted by 73RS
Builder,
You can get a 377 from a 350 block, you just have to use a 400 crank and not bore the block, hence a 377.

Hi 73RS,

Okay, now I am confused again. If you read the first reply, Tech said "apparently (I) don't even know how to start building a 377, much less how to pick the right parts to keep it together at 8,000 rpm's..." Just plugging the numbers into my calculator, both methods come out as a 377. Both methods = 400 block with 350 crank, 350 block with 400 crank.

I presently have a 377 in my 73 Camaro, it's a high revving version redline at 7800 though have had it to 8200 by accident. It's a good running motor and would do very well in a light car like you intend to build. I don't have all of the good stuff you plan on putting in the one you intend to build. I am running a 4 bolt 400 block, stock forged steel chevy crank and stock rods that were polished and shot peened. Running flat top forged full floating pistons, Victor Jr. Heads and super victor intake, topped by a 750 carb shop double pumper holley. Have a lunati cam 260 intake duration and 266 exhaust duration with .640 lift with 1.6:1 rockers, and lifters, driven by a pete jackson gear drive, the quiet one.

Nice! So, you are running the 400 at 30 over and 350 crank making the kind of RPM I am looking for. Have you put it on the dyno?

To get the power you want out of the 377 your gonna have to go with a really stout compression ratio or supercharge it. A blower is much more streetable depending on boost. It's a whole lot easier to get the kinda HP your looking for with a big cubic inch motor, such as a crate 572 from chevy, and you could probably be in about the same price range as building the 377 to that kind of HP. The streetable version of the 572 has 620 HP and the race version has 720 but you have to run race fuel as the compression is up there, think it's 13 to one. I regret not putting a bigblock in my car all of the time.

I hear'ya... Unfortunately, a BBC won't fit in the "stock" design. And there isn't much room for a blower. I have seen a twin-turbo setup though. It was crammed and had major cooling issues. Forced induction may be the only way to get the power, though.

Another option is one of the stroked up small blocks, I've seen them as high as 455 cubic inches, but that's pushing the limit on the block and all of those other moving parts.

The faster revving 377 is probably more appropriate for the trans...so I don't have to replace all of the gears. My guess is that the shorter crank of the 400 block and 350 crank will handle the RPM better than the 350 with the 400 crank...less feet/second for the pistons. This is why I am considering the software dyno...to play around with some of these figures. It would be great if I had the experience and could say, "Oh yeah, just put these parts in that block and you've got it." Short of calling the guy at American Speed, I am not sure of another way to get this done. Here's an interesting site with various calculators: http://www.bgsoflex.com/auto.html