Chevy Small Block 385ci - Stock Block Brawler

Moderate Mouse - The top half of our Nova’s 385ci stock block brawler

Jake Amatisto Nov 11, 2013 0 Comment(s)
View Full Gallery

With how much ink LS engines are getting in other publications these days, we’re actually proud we’re going with a conventional small-block in our Hardtop Hellion Nova project car. The standard SBC is still a great platform that can make loads of reliable power for under $10,000, and it’s our engine builder, Mark Rapp’s specialty. However, we’re not going to ignore the LS engine’s bang-for-the-buck advantage. But for our Chevy II, we felt a conventional SBC would be more ideal for a couple reasons, mainly for ease of install. Of course folks have dropped GM’s late small-block in these little cars before, but we didn’t want to have too many curve balls to deal with–such as oil pan fitment, accessory clearance, and headers. With a conventional engine, we’re able to use a readily available oil pan from Moroso (that will clear a manual steering link with the slave cylinder removed) and the big one: We could run fenderwell headers; something we’ve wanted since we first saw Hooker’s Super Comps on Chevy II drag cars.

Our goal is not to make as much power as possible (you’ll be able to tell that from the mild cam we chose), nor is it to make it a gas saver; we want something we can fire up and drive in traffic every day, if we wanted to. This engine will likely be upgraded to make more power naturally aspirated as the project progresses.

385ci Small Block 2/24

The combination consists of a very simple 0.040-over 383ci with 10.65:1 compression using off-the-shelf parts and a stock block, all of which could be had from Summit Racing. Our goal is to make around 500 hp on 91 octane pump gas, and considerably more with a hefty shot of nitrous. We chose affordable and quality components from Scat Enterprises, COMP Cams, Moroso, TCI, and Summit Racing and put together a custom 385ci bullet for our project–one that can be replicated for around $9,000 from the carburetor to oil pan. Thanks to Summit Racing’s line of blocks and aluminum heads, we were able to keep costs relatively low, and by using full kits instead of piecing out parts individually, we were able to save additional green.

While it’s true we purposely went with out-of-the-box parts to keep the overall cost from skyrocketing, we are running some more high-end parts such as the Black Diamond Quick Fuel carb and Moroso valve covers that will make this pump gas mouse look like a trick race piece. In a previous issue we covered the short-block build, which, with help from L&R Engines and Mark Rapp of Rapp Racing, we were able to build a solid, stock block foundation. The bottom end basics include a Scat 3.75-inch forged crankshaft, Scat’s 6.000-inch forged H-beam rods, Mahle flat top PowerPak pistons and ARP hardware. We also upgraded to a full Moroso oiling system, including their louvered windage tray and Chevy II swap oil pan. In this installment we cover the details of the top end before we haul this moderate small-block to the engine dyno to see what our recipe can do. In the next couple months we hope to not only have the dyno results, but we should also be closer to getting the Hellion back on the road.


Parts list*

• Summit Racing fully machined block ($700)

• Summit Racing 200cc aluminum heads ($1,100)

• Scat rotating assembly & Mahle pistons ($2,000)

• COMP Cams hydraulic roller cam & lifter kit ($1,000) 

• RHS single plane intake manifold ($300)

• Quick Fuel Q-series carb ($700)

• Moroso oiling & cooling systems ($1,000)

• ARP bolts & Mahle/Clevite gaskets ($200)

• Hooker Super Competition headers ($600)

• TCI Balancer, starter, flywheel ($600)

*Approx.


Comp Cam Camshaft 3/24

The camshaft we chose for our small-block is COMP Cam’s Xtreme Energy hydraulic roller Retro-Fit cam (PN 08-432-8). We actually opted for the whole valvetrain kit from COMP (PN K12-432-8), which comes with the roller lifters, pushrods, timing chain, springs, retainers and valve locks. At Rapp Racing, Keith Black stabbed the cam into the stock block before dialing it in.

Cam 4/24

The cam profile features a dual pattern, 0.510 on the intake and 0.520 on the exhaust with a duration of 230/236 at 0.050, however, the numbers on the intake side will change when the rockers go on.

Camshaft 5/24

The camshaft degreeing revealed it to be 4.5 degrees advanced, which happened to be right where Rapp wanted it. An advanced cam will typically improve drivability and power in the low rpm range.

Hydraulic Roller Installation 6/24

If you are building a hydraulic roller engine from scratch, we recommend ordering COMP Cam’s Hydraulic Roller Installation kit (PN 08-1000). This provides you with the cam retainer, lifter dog bones, and spider retainer you’ll need to install everything.

Comp Cams Hydraulic Roller Installation 7/24

If you are building a hydraulic roller engine from scratch, we recommend ordering COMP Cam’s Hydraulic Roller Installation kit (PN 08-1000). This provides you with the cam retainer, lifter dog bones, and spider retainer you’ll need to install everything.

Aluminum Cylinder 8/24

Summit Racing offers seven different aluminum cylinder heads for small-blocks, but we went with the Street & Strip 200cc versions (PN SUM-162111) for our 385. For a smidge over a grand, these heads come assembled with stainless steel 2.02 intake valves and 1.60 intake valves, and 64cc combustion chambers.

Valve 9/24

The heads come with valve springs, chrome moly retainers, and 7-degree locks. The springs they come with can handle profiles with up to .575 of lift, which covers our little street cam.

64cc Combustion 10/24

The 64cc combustion chambers of these heads feature the ever-popular 2.02/1.60 valve combo. The chamber volume is important in order to achieve the compression ratio we’re after, which is right around 10.65:1, which we achieved by going with a slightly thicker 0.052 headgasket. With a standard 0.041 gasket, Mahle flat tops, and our 64cc chambers, we’d be right at 11:1, but we were able to knock that down for pump gas.

Cnc 11/24

These 200cc castings have some light CNC porting at the first inch of the intake port, but Summit leaves a lot of material for future porting.

Rocker 12/24

The heads come with 3/8 rocker studs, but we opted to change them to larger 7/16-inchers from ARP for valvetrain stability.

Dual Ratio Rocker 13/24

We’re actually running a dual ratio rocker arm setup on this 385 stroker; 1.6 on the intake side, 1.5 on the exhaust. This increase ratio actually ups the duration and final lift of our cam profile, from 0.510 to 0.537; our engine builder, Mark Rapp has had some good success with this setup.

MORE PHOTOS

VIEW FULL GALLERY

COMMENTS

subscribe to the magazine

get digital get print
TO TOP