and Performance Parts and Accessories
1967-69 Small Block to Big Block Engine Swap
Back in the 60's there was no substitute for cubic inches in any kind of car. The only thing that kept you from owning a big-block was, much as today, the wallet-bending dollar. Much of the car-crazy public had to settle for a small block (307, 327, or 350) . Today, many of those who dreamed of a 396, 427, or the awe-inspiring 454 are taking that giant leap by doing what man has done for decades - the engine swap!
The small block to big block swap in any Chevy is relatively easy, provided you have all the necessary tools and parts. When performing this swap in the Camaro or late 60's Nova, Classic Industries has just what the doctor ordered. Tool-wise you'll need access to an engine hoist, an engine stand, jack stands, floor jack, 1 or 2 sets of sockets and wrenches, and maybe a few other common mechanic's tools.
Parts needed will include 2 major items that are critical to this operation: the motor mounts and the engine frame mounts (available from Classic Industries).
The engine frame mounts are particular to the big block engine and also differ between the 67/68 style and the 69 style. The big block-style mounts pull the engine forward away from the firewall and also tilt the engine towards the passenger side (RH side) of the car to make up for the large amount of torque produced by the larger cube engines. Many people have tried to drop in a big block using small block mounts only to discover "no room" between the back of the block and the firewall and the side of the block and the heater core cover - not to mention only 1/4 to 1/2 normal throttle response. Correct frame mounts cure this problem. The mounts are available from Classic Industries (sold as pairs) under Part Numbers #K702 (1967-68), #K701 (1969). These mounts can be used with either original GM or reproduction motor mounts.
If you want your engine compartment to look completely "original," you'll also need a new heater core and cover. On original factory big-block cars without A/C, Chevrolet put the heater hose outlet very close to the passenger side fender - versus right next to the engine block. If you want the factory look, both the big-block heater core (Part # H2239) and the big block heater box (Part # AL303) are available from Classic Industries.
If your car has A/C, a different evaporator core outlet case will be needed. Part number K329 will provide the needed space between the valve cover and the case.
When utilizing power steering on your Camaro with a big block, you will need the correct power steering pump brackets and pulleys. Once a hard part to find, Classic now makes it easy! On 67-68 cars, order pump cradle bracket #C631461 and adjuster brace #3876788. For '69's, use kit #KW418 and your problems are solved. 1969 cars used a big block-only power steering pump, while 67-68's with V8 all used the same pump. Get pulley #KW395 and you'll have that end covered, too.
An often asked question on this swap is: "Why does my engine sit offset 1 inch to the side?" This problem only seems to arise when the small block frame mounts are used.
To ensure proper alignment of the transmission, unbolt the cross member until after the engine is in place. In some instances, new alignment holes may have to be drilled, but again, not until after the engine is in.
The last two items involved with this swap are the exhaust system and accelerator linkage. These will depend on the set-up you chose (I.E.: Headers or manifolds; Mechanical or cable linkage).
Aside from minor adjustments and owner-chosen accessories, that pretty much finishes the swap. Remember that almost everything is now available from Classic Industries.
Let's see..., now just how BIG can that big-block be?
Note: You may also have to replace your front springs with a stiffer set to ensure proper steering and load handling.