Small Block Chevy Buildups - Three-Way Mousefest

327 vs. 355 vs. 383

CHP Staff Aug 1, 2008 0 Comment(s)
0808chp_01_z Small_block_chevy_buildups Chevy_small_blocks 1/24

What began as a three-way staffer shootout quickly changed directions after an editorial powwow. While other outcomes aren't impossible, let's face it, cubic inches usually win these deals. And if they don't, you can expect the small mills to be a bit on the rowdy side. That said, instead of trying to outdo one another with simple peak horsepower numbers, we realized we could provide more relevant information by instead showcasing three very different examples of small-block builds. How different, you ask? Let's just say each motor has its own choice of compression, type of camshaft, and intended use.

Case in point, the FNG, Haggai, wrenched over a 327 that pumped out 391 hp and 382 lb-ft. It may not sound like much, but for someone looking for an affordable powerplant for their cruiser, this is a pretty good avenue to take. Then again, can you say mid 12s in a street car with stickies? When it came to the 355, Nelson took the more aggressive approach with his 11.5:1 compression, solid-roller-packing mouse, and belted out 539 hp at 6,500 and 481 lb-ft at 5,200 rpm. Street motor? Could be, but it's on the lopey side and even he'll tell you that his emphasis was to build something more for the 'strip. As for the 383, it was pretty tame compared to some of our builds in the past; however, it still generated 491 hp and 489 lb-ft and featured plenty of idle vacuum at 14 inches at just 850 rpm-yep, the perfect medium for a daily commuter.

If you're a fan of small-blocks and looking for something from a mild upgrade to a street brawler to a fairly stout street/strip piece, then one of these combinations should suit your fancy. More importantly, any one of them can be had for under $7,000. Of course, this is assuming you already have a few of these components, namely the carburetor, distributor, and wires. Nevertheless, you'll find two price lists, one where we've listed all the core parts, including the manufacturer and their respective part numbers, and the other where we provide the info that'll allow you to mimic our combinations to every last detail. Be sure to e-mail us at chevyhi@sourceinterlink.com and let us know which combo fits your style, and above all, whatever changes you may have preferred. -Henry D

Quick Notes
What We Did
Build three small-blocks

The Final Say
They made horsepower!

Cost (Approx)
$3,200 to $7,000

0808chp_02_z Small_block_chevy_buildups Chevy_355_front_view 2/24

On The Edge 355
Truth be told, I went into this project with a bad attitude. Not that I had a problem with building an engine, mind you. I mean that I wanted to get a bit nasty with this 355ci build and do something out on the edge. Past endeavors have always been built with two ideas in mind: attain nice, fat peak numbers, but get them while maintaining a broad, street-friendly powerband. When compared to these past street/strip efforts, this little beast would be of the strip/street variety; we intended to make as much high-rpm power as possible, something good for ripping off fast e.t.'s at the local digs, and as long as we could at least pretend the thing was streetable, that would be good enough for me.

When we conferred with JMS Racing Engines' Mike Johnson, we quickly decided that we would push the limits for a streetable, pump-gas compression ratio, running somewhere in the neighborhood of 11.5:1. Johnson also thought a bit outside the box, suggesting that we run a long, 6- or 6.125-inch connecting rod. Although the idea was to produce high-rpm horsepower, a long rod usually makes more torque, and we didn't want to be deficient in this area. (In other words, we didn't want a total low-rpm pig.) Dwell time at TDC would also be increased, promoting a more complete burn. We'd also get a favorable rod angle in the bargain, producing less piston rock. Mahle had just the small-dome piston we needed to work with a 6.125-inch rod while producing our desired compression ratio.

Our cylinder heads of choice were Trick Flow's Super 23 Street/Strip lungs. These heads flow well and are a great bargain, especially considering that they come with CNC's combustion chambers. They're available with 64- or 72cc chambers, 195cc intake runners, and several spring packages that can handle up to 0.600-inch lift. We intended to far surpass that figure, however, so we ordered ours bare and outfitted them with Isky springs and hardware to handle up to 0.730-inch lift. That should give you and idea of just how crazy we intended to get with this thing, but our rapidly approaching deadline dictated that we go with a shelf grind instead: 0.640/0.640-inch lift, 272/280 degrees duration, and a 106-degree lobe separation angle.

It's a good-sized cam for a 355, to say the least, but a funny thing happened on our way to the dyno: We came up with the big, high-rpm horsepower number we wanted-539 ponies at 6,500 rpm, to be specific-but we also came up with a pretty broad torque band. Check out the chart, and you'll see that our creation is making more than 400 lb-ft from 3,800 rpm all the way to 6,900. Our backup cam choice is indeed radical, but damned if we didn't end with a usable powerband in the bargain, thanks to all that duration and the tight LSA. Reading the cylinder pressure numbers from our runs, our dyno guru Steve Brul concluded that we'd hit on an efficient combo, leading to all the torque that came along with our horsepower.

This thing is rumpity as a Harley, to be sure, and idle vacuum (at 1,200 rpm) is a miniscule 4.5 inches. Is it streetable? With a converter and gears, sure it is. We used 100-octane for our testing, but with a little less timing it'll even run on 91. In the end, we got more than we bargained for: a nasty but stout little mouse that can run hard up top but still get out of its own way down low. What did we learn? Every once in a while, things actually go better than planned. -JN

Nelson's Hookup

ARP
800.826.3045
arp-bolts.com

Autotronic Controls Corporation (MSD Ignition)
915.857.5200
msdignition.com

Federal Mogul (Fel-Pro Gaskets)
248.354.7700
federal-mogul.com

Holley Performance Products/Weiand
270.782.2900
holley.com

Isky Racing Cams
323.770.0930
iskycams.com

Jegs High Performance
800.345.4545
jegs.com

JMS Racing Engines
626.579.4567
jmsracing.com

Moroso
203.453.6571
moroso.com

Rockett Brand Racing Fuel
800.345.0076
rockettbrand.com

RPM International
800.981.0776
rpmmaxx.com

Spectre Performance
909.673.9800
spectreperformance.com

Summit Racing
800.230.3030
summitracing.com

Trick Flow Specialties
330.630.1555
trickflow.com

Westech Performance
951.685.4767
westechperformance.com

0808chp_09_z Small_block_chevy_buildups Chevy_383_front_view 9/24

383 Street Fighter
I'm almost ashamed to admit this, but truth be told, I've never purchased a dual-plane manifold before. Sounds a bit odd, right? If you've followed any of the engine builds I've been involved with over the years, you'll find that I've always been into peak power figures and have had little concern for idle vacuum whatsoever. As for drivability, I've generally held a steadfast opinion that anything is drivable. Then again, my background has been more heavily influenced by dragstrip antics than street light blasts.

This time around, things are a little different. Recently I had the opportunity of cruising the streets of SoCal in two sexy hot rods: a '66 Chevelle and a '71 Camaro, both powered by mid-400hp 383s. And considering I rolled around in them for nearly a week straight, it hit me like a runaway train that I thoroughly enjoyed their mild yet potent street demeanor, and as a result, pushed me into the build you see here.

The angle of attack for this mule was to build something that could propel a 3,400-pound street machine out of its own way, but again, in a manner that wouldn't compromise streetability. This had to be something you could drive on a daily basis with little concern for anything but enjoying the road. It also had to have gobs of torque and only crave pump gas swill, which is the No. 1 reason I opted for the added cubic inches of a 383 with a moderate 9.4:1 compression. Handling the bottom end was Coast High Performance out of Torrance, California, while up top an Edelbrock RPM Air Gap manifold was mated to a killer set of AFR 195cc Eliminator cylinder heads. For the choice of cam, with the help of Tony Mamo from AFR, we felt Comp Cams' hydraulic roller with 224/236 degrees of duration at 0.050 and 0.502/0.520-inch lift on the intake/exhaust was the way to go. Let me tell you, the mild cam didn't hurt us one bit and this combination flat-out works.

0808chp_10_z Small_block_chevy_buildups Coast_high_performance_shortblock 10/24

It's hard to beat Coast High Performance's $2,800 short-block that comes with a 4340 crankshaft and rods, including the company's line of SRS pistons. If you're looking to shave a few bucks, Coast also offers a cast crank with 5140 forged rods and FPS pistons that are 75 percent stronger than their cast and hypereutectic counterparts for just $2,400.

On the dyno, curiosity got the best of us and we wanted to check out the differences between the Holley 650- and 750-cfm Street HPs. We figured the big numbers would come from the larger 750 while the smaller 650 would produce better street manners. We'll have to test the latter part of the theory once we drop it in the mule, but given the cubic inches, I'm fairly certain that the 750 will be just fine. The results: The 750 HP produced 491 hp at 6,000 rpm and 489 lb-ft at 4,600 rpm, which is 11 more horsepower over the smaller 650 HP with 480 hp at 6,100 rpm and 8 lb-ft over at 4,500 rpm. This baby even pulls well over 14 inches of vacuum at 850 rpms!

Admittedly, we searched for that last bit of power in hopes of cracking the 500 hp mark, but it just wasn't meant to be. We ended up testing a 1-inch open spacer followed by a 1-inch tapered spacer, only it didn't make a bit of difference on this combination. For what it's worth, we originally planned on using a set of 1.6 ratio rockers; unfortunately, we had the wrong rocker studs and had to instead go with a set of 1.52 rockers. It's hard to say whether or not that would have gotten us over the hump; that'll be a test for another day. Until then, read up and check out this bad boy. -HD

H's Hookup

Air Flow Research
877.892.8844
airflowresearch.com

ARP
800.826.3045
arp-bolts.com

Coast High Performance
310.784.1010
coasthigh.com

Comp Cams
800.999.0853
compcams.com

Edelbrock Corp.
310.781.2222
edelbrock.com

Federal Mogul (Fel-Pro Gaskets)
248.354.7700
federal-mogul.com

Holley Performance Products
270.782.2900
holley.com

Jegs High Performance
800.345.4545
jegs.com

Milodon
805.577.5950
milodon.com

Performance Distributors
901.396.5782
performancedistributors.com

Spectre Performance
909.673.9800
spectreperformance.com

Summit Racing
800.230.3030
summitracing.com

0808chp_17_z Small_block_chevy_buildups Chevy_327_front_view 17/24

The Misfit 327
To be completely honest, I was a bit skeptical when I volunteered myself to put together a 327 for our three-way build, as in my eyes, the 327 has always seemed like an outcast, shunned by the other small-blocks as a weakling and cast aside for more important jobs. Sadly, it's never really gotten its due. I knew it was going to be tough to try to play in the street with the other bad boys of the hood, but I knew it could be done with the right parts and with less money. Predictions and trash-talk were running rampant in the office as to how much power we could get out of this little guy, but the 327 made it through without so much as a hiccup.

After we contacted Mark Plotner from Powerhouse Engine Components in Bakersfield, California, he set us up with an original 327 block, bored and machined 0.030 over. He also offered up his complete, balanced 327 rotating assembly with cast flat-top pistons. While this foundation is nearly stock, we were trying to keep costs at bay so we could spend our loot on a more efficient top end. In this case, we went with Dart's SBC top end kit, which came with everything we needed to complete the build. At only 1,500 bucks for the stuff, it was perfect.

Initially, on the dyno, the motor wasn't happy. Upon some investigation, we realized the timing pointer on the timing cover had been installed upside down, in turn giving us the wrong reading. As a matter of fact, we were 10 degrees off, and once we got the timing correct at 35 degrees, we recorded a baseline of 346 hp. We weren't pleased just yet and we knew there was still some hidden power to be found. The fuel curve was pretty fat so we got after it and took out some fuel in the primaries and secondaries-even bumping up the timing to 39 degrees. We then hit 371 hp on the next run. The fuel curve was perfect but we still weren't that impressed. We opted for a 1-inch open style Wilson Manifold spacer and gained 10 hp. At that point, the 327 was still making power so we took it a step further and added a 2-inch tapered Wilson spacer and gained another 10 hp. Our final number netted us 391 hp and 381 lb-ft with no drop in power down low! It was rather impressive, to say the least, and the cost to produce it was even better. -SH

FNG's Hookup

Comp Cams
800.999.0853
compcams.com

Dart Machinery
248.362.1188
dartheads.com

Holley
270.782.2900
holley.com

Jegs High Performance
800.345.4545
jegs.com

Pertronix
909.599.5955
pertronix.com

Canton Racing Products
203.481.9460
cantonracingproducts.com

Powerhouse Engine Components
661.861.0125
enginekits.com

Scorpion Performance
954.779.3600
scorpionperformance.com

Summit Racing
800.230.3030
summitracing.com

TCI
662.224.8972
tciauto.com

Wilson Manifolds
954.771.6216
wilsonmanifolds.com

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