Cary's Ultimate Small Block Crate Motor

I installed what I believe to be the Ultimate Small Block Crate Motor in Nan's 56.  However, you can't buy this engine; you have to assemble it from a few GM Performance parts.

My requirements were:

• The engine had to be fuel injected;
• It needed to fit the stock Corvette Motor mounts
• It had to run smoothly enough to support power brakes
• It had to have at least 400 HP

A logical way to meet the first three requirements is to purchase the GM Performance Ram Jet 350.  This is a good engine and has the very nice Ram Jet Fuel Injection system.  The GM Part number is 12499120; the price is about $5,750.  It is rated at 350 horsepower with a hydraulic roller cam, 1.6 to 1 ratio roller rockers.  The disadvantages of this engine are that it has cast iron cylinder heads and the crankshaft has two bolt main caps.

An alternative to the Ram Jet 350 is to buy the Fastburn 385 engine (P/N 19201331) and install the Ram Jet Fuel Injection system (P/N 12498032).  The chart below shows the comparison.  So far (knock on wood) the Fastburn 385 with the Ram Jet FI unit starts easily, runs smoothly, and has lots of power.

   

Component / Measure	Ram Jet 350	Fastburn 385
Crankshaft Main bearings	2 bolt	4 bolt
Cylinder heads	Cast iron	Aluminum
Intake valves	1.94	2.02
Exhaust valves	1.50	1.55
Compression ratio	9.4	9.6
Intake lift	0.431	0.474
Exhaust lift	0.451	0.510
Horse power	350	385
Torque	400 @ 5500 RPM	385 @ 3800 RPM