I have bought many crate motors and will tell you that while they are very good investments for your car and perform quite well, they sound like your mothers oldsmobile..... if you are looking for that cam sound. The reason is selection of very mild cams and roller ones at that for some of the crate motors from GM Performance Parts. The performance from these engines is very good for the dollar and of course come with a great warranty. That's good.
On the other side is some aftermarket motor building houses such as American Speed to name one, that will build you a more uden uden uden type sounding engine. Combined with chambered exhausts and full length headers....well, it's heavenly sounding to a rodder such as yourself.
Buying a crate motor and figuring on a cam change for both performance and sound can be done, but now you are talking about possibly making changes to other things on these crate motors because of their mechanical restrictions on the valve train/heads which puts you into the spending money abyss.
I would say that the GM PP 330hp with chambered exhausts sounds pretty good for a start and is the "best" buy for the buck. The ZZ4 will outperform the 330hp version, but sounds like crap in my opinion.
I would tell you that a purchased short block, add Edelbrock 64 CC heads, Edelbrock RPM performer intake and Carb, comp cams XE 268hyd cam, HEI, full length headers, chambered exhausts, and it will be awsome! If you have a four speed you could go up to the XE 274 for alittle more hp, and alot more cam sound.
Whatever your choice, good luck and have fun.
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