AmericanPie

I'm looking at a couple of '69 Corvettes for sale; both are mint originals with the L-46 motor. I grew up in this era but never realized how popular this motor was. I always assumed it was merely a 350-cube version of the L-79 but now I notice it has a cast iron intake (as opposed to the L-79's aluminum one). It almost seems as though Chevy made it more of a "yeoman" type of motor with less emphasis on performance. Both of these cars even have A/C.

Now I'm curious; what else is different between these motors? Does the L-46 share the L-79's cam, 11.0-1 compression, and big-valve heads? Does a high-rise intake even fit under the stock C3 hood, and if so does it add much power?

Also, is the 1970 LT-1 basically the same motor as the L-46, except with a solid lifter cam, aluminum intake and big carb?

I'd like to get this stuff straightened out before I continue shopping. Thanks!

wfo76

There are owners of all three cars here. I have always liked the 69 with the stock small block hood and 350/350 so will throw my two cents in.


Both engines used Iron intakes, only the LT-1 was Aluminum.




???, both engines should run similar.




A/C always optional on hydraulic lifter small blocks and is another good reason to like this engine.




Engines are basically the same except the L-46 uses a longer duration dual profile cam which would also be used on the L-82, same compression and 2.02/1.60 valve sizes. There was a post here not long ago and I think the consensus was the Z-28/LT-1 Aluminum intake does not fit under the stock small block hood with the factory air cleaner base, but will with a drop base. Don't know how much power it adds but just looking at the two intakes the hi-rise intake has to be better.



Yes along with no A/C available and transistor ignition standard on the LT-1. The early 70 LT-1s did not have power steering available. Transmissions and axle ratios the same on both the L-79/L-46 and the LT-1. It is a good engine and is basically an L-82 with about 10 or 10.5 to 1 compression (rated at 11 to 1 but always less). All three engines are 4-speed only, no automatics. For an A/C car, it would probably give the 72 LT-1 a run for it's money although I would bet on the LT-1.

Good luck.

AmericanPie

[QUOTE=wfo76]Both engines used Iron intakes, only the LT-1 was Aluminum.QUOTE]

Thanks for the quick and thorough reply! You've answered most of my questions. However, I'm pretty sure the L-79, like the LT-1, used an aluminum intake. There must be some HP loss with the iron intake on the L-46; I think it's a low-rise design, in order to fit under the C3's small-block hood. I'd imagine the L-46 is a real nice all-around street motor. Lots of guys like the L-79 but the L-46 has the added benefit of a longer stroke (and therefore more torque). Maybe not quite as much high-rpm breathing ability however.

...I just checked Calvin and you're right; the '68 L-79 used a low rise, cast iron intake unlike the C2 L-79's which were aluminum hi-risers.