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355ci Small Block - The Spruced GooseA Power-Packed 355 Small-Block For The Street From the September, 2010 issue of Chevy High Performance By Sean Haggai Photography by Sean Haggai
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What We Did
Give an old-school 355ci a new look and a lot more power Bottom Line
We gained 111 hp and 600 rpm on the dyno with a simple top-end kit Don't let the exterior fool... Don't let the exterior fool you, our little engine was kept in good order and produced decent power on the engine dyno. Our candidate for this project makeover consisted of a 355ci small-block that had a cam and roller rocker update at some point in its life. On the dyno, our gem made a reliable 365 hp at 5,500 rpm and 390 lb-ft at 4,300 rpm. Mystery engines are always more entertaining than their crate/off-the-shelf brethren; not knowing what's on the inside can make them more or less interesting real fast. Our mystery motor could have high-compression pistons with forged internals ... or it could have a less-than-willing stock bottom end with a set of beat-up main bearings-it's just part of the deal when getting into a running car or engine secondhand. Originally, this little goose sat between the framerails of a second-gen Camaro, Henry D's project F73, to be exact. And as most of you know, we pulled this old slug from the car to perform a perfect summer makeover and also to give us as much room as possible for the chassis to be retrofitted with an all-new Detroit Speed suspension. Considering our little mill was in perfect running order before we pulled it, we couldn't think of a better way to showcase its power potential than with a complete makeover-all of which would only call for bolt-ons while leaving the bottom end alone. We wanted to keep the costs down and keep the work performed to a minimum. The 355 featured a set of vintage cast-iron Corvette heads, a leaky oil pan, a stamped timing cover, and an older dual-plane manifold. Not exactly modern, but a solid performer nonetheless. First to go were the finned-style... First to go were the finned-style valve covers and cast-iron heads. Don't discount these just yet; we have another life planned for these in an upcoming build. We outlined this build with a few basic rules: increase breathing with airflow, supply ample fuel, and maximize the power for the street. The major makeover components consisted of a set of heavy-puffing aluminum CNC-ported Brodix heads, single plane manifold, and a Comp valvetrain. While our unkown cam was pulled, we relied on a high-lift 0.520/0.540-inch intake/exhaust with 236/242 degrees of duration at 0.050-inch. It all sat on 110 degrees of lobe separation. Topping it off is a gasket-matched SP1 single-plane manifold, also from Brodix. For good measure, we replaced our oiling system with all Moroso pieces, including a high-volume oil pump and pickup, and a deeper sump pan with screen. To maintain our street creed, we upgraded the fuel delivery with a 750-cfm Quick Fuel Technology carburetor and placed our confidence in a drop-in, ready-to-go MSD distributor. We enlisted Westech Performance Center in Mira Loma, California, to get us baseline numbers from the original setup. With numbers in hand, we tore down the small-block and took care of its aging looks with a fresh coat of Chevy Orange paint. Was it worth the effort? Considering it took all of two days-one for the teardown and rebuild and another spent on the dyno-111 additional ponies was well worth it, almost too easy to be honest. Tag along to see how we did it and how to do your own small-block makeover.  Once we got inside the motor,...  Once we got inside the motor, it was clear someone had given it attention. It featured upgraded hydraulic flat-tappets and beefier Comp roller rockers with a 1.6:1 ratio. We used a 5/8-inch socket to remove the old rockers.  Our cast-iron heads were in...  Our cast-iron heads were in pretty good shape, but they hardly stack up to the modern CNC-ported aluminum heads we're upgrading to. Add in the weight savings and improved cooling efficiency with the aluminum pieces and it makes them hard to beat. Since we are utilizing a complete Brodix top-end kit that comes with new bolts and gaskets, there was no need to keep the old stuff.  Removing the old timing gear,...  Removing the old timing gear, chain, and lower crank gear was a cinch. Then we pulled out the old stick and checked the cam bearings for wear. Our new Comp cam should really bump things up a notch. After all, with 0.520/0.540-inch intake/exhaust lift, the new cam should be able to take advantage of the larger Brodix lungs. We washed the cam in solvent to remove any rust inhibitors and foreign material, applied engine assembly lube, and slid it into place.  Moving right along, we installed...  Moving right along, we installed our brand-new double-roller timing chain with a billet gear and lower crank gear. All we had to do was line up the timing marks and set it in place with the supplied hardware and cam plate. We also installed the supplied plastic cam button and began to set up the engine for cam thrust. Spray Booth
We're sprucing this powerplant not only for power, but for looks as well. We steam-cleaned our 355 small-block before it was torn down to remove all the oil residue and road grime. A trip to the local auto parts store scored us a couple cans of Dupli-Color DE1620 Chevrolet Orange spray paint. Nice and bright, just the way we like it-and it only took us about an hour to paint the block, using a piece of cardboard to avoid getting overspray on the internals. Note: Wipe down all gasket surfaces with a solvent or lacquer to remove overspray.  Before the thrust could be...  Before the thrust could be checked, we needed to install the Comp Cams two-piece timing cover. This not only made for checking the thrust very easy, but any future cam swaps we may have planned will allow for the removal of the top cover, leaving the timing cover gasket undisturbed. It also prevents having to drop the pan for this job.  We installed the top cover...  We installed the top cover onto the front of the engine and removed the small Allen plug. We placed a dial indicator onto the end of the cam and checked for thrust. Ideally, we'd want to see something between 0.006 and 0.010 inch, but our initial check of the cam revealed we had no cam thrust whatsoever. Using the plastic cam button, we could clearance until we reached our ideal thrust measurement. We trimmed enough to gain 0.008-inch thrust. From there we proceeded to degree the cam straight up.  After an overnight soak in...  After an overnight soak in an oil bath, we removed our new Comp CS R-series hydraulic roller lifters. These come preassembled with link bars and will allow our 355ci to rev more freely and lower the valvetrain loss normally associated with flat-tappets. Our set worked perfectly, and since they have an 0.842-inch outside diameter, they fit our factory lifter bores.  Although our old set was also...  Although our old set was also from Comp, we couldn't help but splurge a bit when it came to upgrading to newer and stronger rollers. The most noticeable difference is the nearly unbreakable 8650 chromoly body. The arched, weblike design delivers a nearly 29 percent increase in strength and rigidity. A black-oxide exterior finish looks cool while ensuring long-term corrosive resistance. They also feature unique hardened roller tips for reduced friction and eliminates valve stem side-loading. The Ultra rocker arms also feature a fully rebuildable design. We installed our set and locked them down with the supplied hardware.  After laying down the Brodix-supplied...  After laying down the Brodix-supplied intake gaskets, Ernie Mena gently lowered the gasket-matched Brodix SP1 manifold. Once down, we secured it in place using the supplied hardware.  Front man Steve Brulé prepped...  Front man Steve Brulé prepped our small-block's valvetrain by lashing the valves. Good news: Since it's hydraulic, our lash was set to zero.  Next, we rolled the engine...  Next, we rolled the engine over and removed the older pump and pickup. While the unit we pulled out was still in working order, our deeper sump pan and increased rev characteristics means our engine would need more oil control and pressure. We replaced it with a new Moroso unit the pickup already attached. Our new Moroso pan was next. The pan's kick-outs are functional and will hold more oil and with its pre-installed screen, oil slosh is kept to a minimum. We laid down a one-piece oil pan gasket with a dab of silicone on each corner of the block and bolted the unit down. The Goods
Brodix did all the hard work, making our decision to use this top end kit easy. Their IK (Iron Killer) small-block combo package comes with off-the-shelf components that act like custom one-off pieces. The intake and exhaust ports have extensive CNC work and even come with cleaned and blended bowls. The IK cylinder heads come completely assembled with 11/32-inch intake/exhaust valve stems. Brodix takes it to another level by match-porting the intakes to mate up perfectly to its SP1 single-plane manifold. The combo kit comes complete with intake, exhaust, and head gaskets; NGK B8ES spark plugs; and taller "BRODIX"-cut valve covers. Brodix also flow-tests its valve job-you can't beat that! Fuel Delivery
Our Quick Fuel carburetor was a no-brainer. Not only does it look the part, but our Q-series performed as well as we could have hoped. The Q-series comes with extended jets for easy changes, mechanical secondaries, and a billet throttle body assembly, all good for 850 cfm. Using the supplied carb gasket we tightened it down with a 1/2-inch wrench.
| Q-850 |
| Primary Main Jet |
76 |
| Primary Nozzle |
33 |
| Secondary Jet |
84 |
| Secondary Nozzle |
33 |
| Pri Idle Air Bleed |
70 |
| Needle & Seat |
120 |
| Hi Speed Bleed |
33 |
| Power Valve |
4.5 |
The Shopping Cart
| MFG |
DESCRIPTION |
PN |
COST |
| BRODIX |
Iron Killer CNC 210cc cylinder heads |
9991014 |
$2,840 |
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Port match intake manifold |
PS MI M |
172 |
| COMP CAMS |
Hydraulic roller lifters "R" series |
885-16 |
466 |
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Ultra Pro Mag rockers |
1604-16 |
324 |
| Billet timing set |
7100 |
89 |
| Fiber cam button |
202 |
3 |
| Cam lock plate |
4605 |
5 |
| Front two-piece timing cover |
210 |
216 |
| XR288HR-10 hydraulic roller camshaft |
12-433-8 |
266 |
| MOROSO |
Oil pan with screen |
20191 |
200 |
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Oil pump with pickup, including shaft |
22138 |
138 |
| MSD |
Pro-billet V-8 small-block distributor |
85551 |
222 |
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Black distributor cap |
84333 |
30 |
| QUICK FUEL |
850-cfm 4BBL carburetor |
Q-850 |
676 |
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Total |
$5,647 |
STREET WORTH
Fuel: 91 octane • Timing: 34 degrees
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BEFORE |
AFTER |
| RPM |
TQ |
HP |
TQ |
HP |
| 3,000 |
363 |
207 |
358 |
204 |
| 3,100 |
363 |
214 |
358 |
211 |
| 3,200 |
365 |
223 |
362 |
221 |
| 3,300 |
370 |
232 |
370 |
233 |
| 3,400 |
375 |
243 |
377 |
244 |
| 3,500 |
379 |
253 |
384 |
256 |
| 3,600 |
383 |
263 |
390 |
267 |
| 3,700 |
387 |
272 |
397 |
280 |
| 3,800 |
388 |
281 |
403 |
291 |
| 3,900 |
389 |
289 |
406 |
301 |
| 4,000 |
389 |
296 |
407 |
310 |
| 4,100 |
390 |
304 |
407 |
318 |
| 4,200 |
390 |
312 |
408 |
326 |
| 4,300 |
390 |
320 |
411 |
336 |
| 4,400 |
388 |
325 |
415 |
348 |
| 4,500 |
384 |
329 |
421 |
361 |
| 4,600 |
382 |
334 |
425 |
372 |
| 4,700 |
379 |
340 |
427 |
383 |
| 4,800 |
378 |
346 |
431 |
394 |
| 4,900 |
375 |
350 |
435 |
406 |
| 5,000 |
371 |
353 |
438 |
417 |
| 5,100 |
366 |
355 |
440 |
427 |
| 5,200 |
362 |
358 |
439 |
435 |
| 5,300 |
358 |
361 |
438 |
442 |
| 5,400 |
354 |
363 |
435 |
448 |
| 5,500 |
348 |
365 |
432 |
452 |
| 5,600 |
342 |
365 |
428 |
456 |
| 5,700 |
335 |
363 |
424 |
460 |
| 5,800 |
~ |
~ |
420 |
464 |
| 5,900 |
~ |
~ |
416 |
467 |
| 6,000 |
~ |
~ |
412 |
471 |
| 6,100 |
~ |
~ |
409 |
475 |
| 6,200 |
~ |
~ |
403 |
476 |
| 6,300 |
~ |
~ |
391 |
467 |
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BEFORE |
AFTER |
| AVG TQ |
373 |
409 |
| AVG HP |
308 |
318 |
| PEAK TQ |
390 @ 4,200 |
440 @ 5,100 |
| PEAK HP |
365 @ 5,500 |
476 @ 6,200 |
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