Chevrolet Performance SP350/385 crate engine swap

If you’ve been into Chevrolet performance for any time at all and sport graying temples you understand the way it used to be. We once lived in an era without options. You just couldn’t go out and buy a precision-built crate engine for your Chevelle, Camaro, or Nova. You had engine failure or the darned thing was just plum worn out. There was the need for a quick solution and there wasn’t one to be found anywhere short of a gambling journey to the local salvage yard or a rebuilt engine from Pep Boys or a nearby Sears Automotive Store back in the day (yes, you used to be able to buy engines from Sears).

In those days, we drove to the salvage yard with a toolbox, found a cast-iron hopeful tucked between the fenders of a smashed-up Chevelle, and hauled it home in hopes it was void of unpleasant noises and excessive oil consumption. Few things were more deflating than a weekend spent installing a junkyard engine only to discover it was worse than what you pulled out.

Today, we live in an age where it has never been easier to get right back into power with a warranty thanks to the SP350/385 Turn-Key small-block 350ci V-8 package from Chevrolet Performance.

As incredible as it may seem, the legendary small-block Chevy has been in continuous production for more than 62 years, the longest engine production run in American automotive history. Why? Because we love the Gen I small-block Chevy V-8 in all its many forms and are still willing to buy new ones from anyone willing to manufacture them. Chevrolet Performance continues to offer the small-block Chevy because these engines are as viable as they ever were and still engineered to make a lot of power for the money.

The SP350/385 Turn-Key crate engine employs new fast-burn aluminum cylinder heads equipped with LS-style beehive valvesprings for greater high-rpm performance. The lightweight aluminum cylinder head casting is based on the proven Fast Burn chamber design, with large intake runners and 2.000/1.550-inch valves.

These fast-burn heads allow the SP350/385 to rev higher to make the most of every cubic inch of air that passes through them. The engine consists of a new iron block with four-bolt mains, a forged-steel crankshaft, aggressive hydraulic roller camshaft, and durable high-silicon hypereutectic pistons. Hypereutectic pistons have excellent expansion properties, which means no cold-start rattle.

What makes the SP350/385 (385 horsepower) a great value is everything you need to heat up the headers, including the distributor, carburetor, and balancer, is already installed. The starter, fuel pump, air-conditioning compressor, alternator, front-end accessory drive kit, and more are also included and ready for you to install, making it turnkey and ready to go. CHP

 

Joel Rode of Hot Rod Specialties in Upland, California, has uncrated the SP350/385 and goes right to work dressing it up for installation. The crate package arrives on your doorstep complete with everything you’re going to need for installation. Before you order the SP350, ascertain your application because you may not need everything in the kit. You may be better off with a comparable SP350 Base long-block from Chevrolet and amassing the bolt-on components you’re going to need.
The SP350 is dressed and ready for a test-fit. We stress a test-fit because the existing small-block in Joel’s 1969 Nova is fitted with an Eddie Motorsports front drive system, PerTronix ignition, and Doug’s headers. We’re going to show you how easy the engine is to dress and install.
Joel begins removal of a road-worn 350ci Chevrolet, which has been a faithful servant. When he discovered the SP350 crate option and how affordable it was, he just couldn’t pass it up. When you consider the cost of an engine rebuild and the downtime involved, the SP350 is very attractive.
The SP350 Turn-Key crate arrives with a 153-tooth flexplate. Joel’s 350 has a 168-tooth flexplate. In Joel’s case, with a 700-R4 with a TCI torque converter, he can go with either the 153- or 168-tooth flexplate. We like this dated 350 Chevrolet with its iron heads, which are more old-school.
Here’s a closer look at the SP350/385 Turn-Key engine. This is a factory-style front drive system with alternator, power steering pump, and pancake air-conditioning compressor. You may encounter space issues with some aftermarket radiators. Also keep in mind the need for a correct engine-driven fan designed for serpentine belt-drive use, which gets air moving in the right direction.
Joel’s small-block has an Eddie Motorsports front drive system, which he would prefer to use on the SP350 crate. Joel is going to deck the engine with the Chevrolet Performance drive system to ensure there is enough clearance with his aftermarket radiator then switch over to the Eddie Motorsports drive system.
Chevrolet Performance provides a complete HEI ignition system, including ignition wires. Joel is setting the ignition system up at this time. We like the routing of these ignition wires because this approach prevents crossfire and looks sharp.
Joel’s small-block is fitted with this 168-tooth flexplate, which will not be transferred to the SP350. The 168-tooth flexplate calls for an angle-bolt starter, but the SP350 is fitted with the 153-tooth flexplate, which gets the parallel-bolt starter.
Joel’s Nova was factory-fitted with a 250ci Chevy inline-six. When a previous owner did the swap to a 350 small-block, they erred in welding the engine mount brackets to the subframe, throwing the engine-to-chassis alignment off.
The SP350, with its stock, 1990’s-vintage serpentine front drive system clears the wide aftermarket radiator and electric cooling fans with plenty of room to spare.
Chevrolet Performance provides this mechanical fuel pump with the SP350 engine swap package. Joel ran into clearance issues between the fuel pump and the subframe when he was decking the engine, which was an issue particular to his Nova.
The larger harmonic damper on the right is provided with the SP350 crate engine. Joel’s 350 has the TCI Rattler harmonic damper on the left, which clears his subframe and front sway bar. He will transfer the TCI Rattler to the SP350, which is internally balanced, so you can swap dampers all day long without consequence.
Joel has chosen to swap the Eddie Motorsports front drive system to the SP350.
Joel had to cut out the aforementioned engine mount brackets, and now the SP350 fits perfectly.
The Eddie Motorsports front drive system clears this generous aftermarket radiator and electric fans with room to spare.
When Joel was decking the engine he discovered a torn rubber engine mount, which could have been catastrophic. He opted for a fresh pair of polyurethane engine mounts from Energy Suspension, which will provide durability and vibration isolation.
Our SP350 has undergone final decking and now it’s time for all those pesky steps necessary to get a fresh engine fired. Because the engine is generously lubricated during assembly, you don’t necessarily have to prime the oiling system, but it is suggested. You can never have too much oil on moving parts.
Joel gets the Doug’s long-tube ceramic-coated headers connected to the exhaust system. It is always a good idea to install new gaskets and check the system for leaks.
Items like the coolant temperature and oil pressure sender can be in different locations depending upon the engine you are replacing. Joel’s 350 had its coolant temperature sender toward the back of the intake manifold. The SP350’s dual-plane intake manifold sports a coolant temperature sender in front, which means Joel will need to add length to the lead wire.
Joel’s 850-cfm Holley from the old 350 will not be swapped to the SP350. However, the dual-feed plumbing will be transferred to the Holley 750-cfm carburetor Chevrolet Performance has provided. Joel admits his 850-cfm atomizer was too large for the 350.
The 750-cfm Holley 4150 is placed and anchored. It’s a good idea to use an insulator gasket between the carburetor and manifold to enable your Holley to run cooler. Chevrolet Performance provides the base gasket and all hardware to get the job done.

 

Sources:

Chevrolet Performance
chevrolet.com/performance

Doug’s Headers
shop.dougsheaders.com

Eddie Motorsports
888.813.1293
eddiemotorsports.com

Energy Suspension
888.913.6374
energysuspension.com

Holley
866.464.6553
holley.com

Hot Rod Specialties
909.215.5516
hotrodspecialties.net

Summit Racing Equipment
800.230.3030
summitracing.com

 

Photos by Nick Licata and Jim Smart