Originally Posted by Father & Son
I have a 69 C20 with the original 350 ci/400 turbo. The 350 runs good but needs freshening up. I prefer to stay with the original 350 but may want to add HP (via 383?), have heard post the 86 350 is superior and crate engines are fairly inexpensive. What are the pros & cons?
Do search for crate engines on this site. Its scary how bad some of them are. Even names that used to be trust worthy are shipping junk motors that dont last 20k miles.
A bore job with the 383 kit and new heads is the best way to go in my opinion. Only bad thing is the crate motor can be swapped in a weekend. Engine rebuild will take longer. Be sure to get a balanced kit with crank rods pistons rings balancer and flexplate all in one kit factory balanced and ready to install. At least these are close and usally run able untouched in a truck. Race car my still require balancing but even then you want a kit that is close not way out of spec.
If you want to buy an engine make sure its a new one from gm. Save yourself the pain of the famous mexican rebuild. Or other such badly done rebuilds. At some point a used motor from the junk yard is more reliable. If its not 100 percent new pass and rebuild the known good engine you have with all new parts from the best people it will last twice as long as the cheap 1500-2500 crate motors.
87 and newer blocks that are roller are cheaper to rebuild with roller cam. This is a fact. But not really any different other wise. Many of the best blocks are what is called high nickel blocks. But most 010 four bolt blocks will take one hell of a lot of abuse before it blows up. If you spend an extra 500 or more for a rebuildable block you are half way to the price of the roller cam for the old block. So you dont save all that much especially if your block is nice and the roller block needs a lot of work at the machine shop. Then the cost is nil.