Here's some musclecar math to think about: a little bit of grease on the hands + some quality time spent in the garage = savings of more than a little dough, and the satisfaction of a job well done to go with it. While this formula can apply to just about any automotive repair job, nowhere is it truer than with a ground-up engine build.
With this theme in mind, we've been detailing the assembly of a budget-minded homegrown stroker mouse motor in the last two issues. In case you missed the previous segments, our short-block was based around a four-bolt 350 block and a 383 stroker kit from Powerhouse Engine Components ("Shoestring Stroker," June 2007). We went on to add parts like as-cast 190cc Powerhouse heads, a hydraulic Elgin cam, and Milodon oil system components to finish our 10.7:1 compression long-block in the July issue. Doing all of the assembly labor ourselves has saved us a good amount of funds, and at the close of business last time, we'd spent right about $3,300 inclusive of all parts, a few engine build tools, and machine work.
Avid readers looking for tons of torque with limited funds have likely been anxiously awaiting this engine's completion. Would we deliver on our promise of big power on a minimal investment, or would we be left to offer Chevy enthusiasts little more than a subpar power quote and an equally unimpressive apology? As you'll see below, our power prayers have been answered-but before getting to that, it's time to put the finishing touches on our mill.
Some of the Milodon engine covers we picked up for this build include a PN 65501 steel timing cover ($14.73) and tall chrome valve covers retailing for $58.32 (PN 85500). These valve covers are baffled and include breather grommets. Why'd we choose a gold timing cover, you ask? Well, it's a couple bucks cheaper than chrome! We also picked up Milodon's $4.76 PN 85260 timing cover bolt set and $9.02 PN 85375 valve cover stud kit (neither shown).
After installing our crank seal into the timing cover, we put our timing cover loosely in place on the block (both the gasket and seal were included in our Powerhouse gasket set). Before the timing cover bolts are installed, it helps to press the harmonic balancer into place, a process that requires a harmonic balancer installer tool (a standard item for most home garages, and readily available). Doing so helps better align the timing cover to the block. Don't forget to use some oil on the seal. With the balancer in place, our Milodon timing cover bolts are installed and torqued to 21 lb-ft.
Milodon also hooked us up with its PN 30901 Low Profile oil pan as well as PN 32102 windage tray, both designed to work with our somewhat-unusual passenger-side-dipstick four-bolt block. These items retail for $201.57 and $29.39, respectively. Since this tray affixes to the block and not the pan, we also grabbed a windage tray installation kit (PN 81150, $52.06).
Milodon's windage tray uses a double-nut design (one above, one below) as its mounting system, which allows the tray height to be adjusted. This lets you ensure proper clearance between it and the spinning rods. After some visual measurements, the nuts receive the specified torque, and the crank is spun to ensure no interference.
After carefully setting all oil pan gaskets in place and applying RTV at all the right spots, the Milodon pan goes on. For $6.37, we got a set of the company's PN 85000 oil pan bolts, which we install and torque to recommended spec. It's time to flip the engine over and move to the topside.
There are seemingly endless choices on the market when it comes to intake manifolds, and a decision here can make a huge difference when it comes to both power and the wallet. A smart choice on both fronts is Weiand's dual-plane Stealth. This manifold line has been newly redesigned using the latest in computational fluid dynamics to help deliver optimal flow for large-displacement motors like our stroker. Carrying PN 8150, its suggested retail is $150.
To secure our intake manifold, we got a set of intake bolts from ARP. This PN, 135-2001, retails for $28.01 and is actually designed for big-block Chevys. ARP recommended them, as they are somewhat longer than small-block versions and work with a greater variety of manifolds (some manifolds are thicker than others, you see). You'll just need to be careful, as some SBC pushrods can be contacted if the intake bolts are too long. Also pictured are a water pump bolt kit (PN 130-3202, $14.73), fuel pump bolt kit (PN 130-1602, $7.23), and alternator bracket bolt kit (PN 130-3302, $5.23)-the final item being one we actually haven't used to date.
After cleaning the head surfaces, we set our Powerhouse-included gaskets on the heads and apply RTV around the coolant jackets. In addition, we're using a bead of RTV along the front and rear edges of the block in lieu of any prone-to-squeeze-out gaskets. We also check and discover that two of our ARP intake bolts are indeed too long (they'll hit the number 4 and 5 exhaust pushrods), so we'll just substitute shorter bolts at these locations.
Our intake is laid in place and the bolts torqued to a final 25 lb-ft using the sequence and specs included in the manifold's instructions. The Stealth's dual-plane design is said to nearly match the horsepower of a single-plane manifold but with a much fatter torque curve-and after all, torque is what strokers are all about.
We're about ready to prime our oil system, but before doing so, we'll need to install the fuel pump. Our mechanical pump is a Holley PN 12-327-11, which is rated at 110 gph, does not require a regulator (it's internally pre-set), and retails for $95. Featuring heavy-duty construction designed for high rpm, its fuel body can be rotated to fit your plumbing needs, which a nice feature.
With all oil passages sealed off (take note of the temporary brass plug in the oil pressure sensor port at the top rear of the block), we can start dumping our SAE 30 break-in oil into the engine through the distributor hole. We also add some break-in concentrate, which is important for a flat-tappet cam. While the oil drips in, we take a moment to install our thermostat and water neck (also acquired locally) onto the front of our manifold, and also use Weiand's provided plug set to stop off all unneeded vacuum and coolant ports in the manifold.
Priming your oil system is fairly critical, as it prevents the possibility of oil starvation to any part of the engine during initial startup. A special tool is needed to turn the oil pump driveshaft (normally spun by a SBC's distributor, of course), and we sourced Powerhouse Products (COMP's tool division) for one of their PN POW101150 Oil Pump Primers. It goes for $22.95.
Powerhouse Products' priming tool is inserted into our distributor hole until it seats onto the oil pump driveshaft. A drill is used to spin the priming tool clockwise. Advice on "how much" to prime the engine differs, but this author feels it's best to run the primer all the way until you can see oil coming out of the top of every pushrod. You can see some beginning to pool beneath the valvesprings if you look closely here.
To finish off our stroker's cooling system, we source a water pump from Milodon. The company sells this PN 16200 high-volume unit for $95.31. To save a few bucks, we're using a steel water pump in lieu of aluminum (while there's a weight difference, it isn't as significant as if we were talking about iron cylinder heads).
Our water pump bolts up front using the provided gaskets and our ARP water pump bolt kit. Also while up here, we turn the crank over so that the timing mark on our balancer shows the firing position for cylinder number one (watch the valves move to ensure you are not at the top of the exhaust stroke instead).
We're ready to bolt our valve covers on. The best way to go is not actually to bolt, but to stud. Valve cover studs like our Milodon units are inexpensive and make installing the valve covers far simpler-they'll line up the covers and help prevent the gaskets from slipping out of place. Just be sure to use some threadlocker to prevent them from backing out should you ever need to take the valve covers off. After torquing the covers down (don't overtighten or you'll squeeze the gaskets out of place), we pop on our locally sourced breathers (not shown).
We grabbed a set of MSD PN 3565 Heli-Core wires for $64.46 as well as a value-laden Street Fire HEI distributor for $159.99 (PN 8362). This distributor is a coil-in-cap style and features quick-and-easy wiring, as well as an adjustable vacuum advance system (via an Allen wrench).
After liberally lubricating the distributor gear with the provided break-in lube, the distributor is installed. It's best to have the distributor cap removed while doing this, as it will help you roughly locate where you want your No. 1 spark plug wire to connect once the cap is on. We mark the distributor housing where the rotor ends up, and, after taking this photo, install the distributor cap and mark our corresponding No. 1 plug wire terminal location. We then secure our distributor using a locally sourced hold-down clamp and bolt. Since we're roughly at the No. 1 firing position, our engine should fire with only slight adjustments to distributor twist.
Our choice to feed this 383 will be a tried-and-true Holley 750-cfm four-barrel carburetor. This particular street/strip model carries PN 0-4779C and retails for $565. Features include dual fuel feed inlets and metering blocks, mechanical secondaries with dual accelerator pumps, Power Valve blowout protection, and a manual choke.
One of the final items we need to tidy up is final tightening of our ARP crank bolt (an item we showed you last time). Use threadlocker on this sucker to make sure it doesn't come out. We install spark plugs in our Powerhouse heads to allow the cylinders to build compression and prevent the engine from turning over while doing so.
Unless you have an engine build stand that affords a bunch of room in the back, you'll need to get the engine off of it before installing the flexplate or flywheel. After bolting the engine into a nifty little rolling cradle we grabbed from Summit, we install our Powerhouse flexplate using the ARP bolt kit we showed you last time. Threadlocker (the red stuff) is important here as well, and make sure you have the balance weight facing forward and the extra hole in the flexplate aligned with the extra hole in the crank (here you can see it at the 10 o'clock position). That'll do it for our engine assembly, so it's time to load this 383 into the back of the official Super Chevy minivan and head to the dyno!
Bolted to the dyno, our 383 was hooked up with your typical array of engine sensors, as well as a fuel source, a starter motor, and the cooling system of the dyno. The dyno room's fuel cell was filled with high-octane VP unleaded to prevent any chance of detonation while tuning (don't worry-we're not about to "trick" you with a race gas tune, folks). We're also using a set of "FlowTech II" ceramic-coated headers, PN 31106FLT ($340.00). These long-tubes fit 1963-82 Corvettes, feature 1 5/8-inch primaries, and were acquired with the purpose of eventually installing this engine into Campisano's personal ride (more to come).
Our baseline run was a good start. With just 30 degrees of total timing, we eclipsed 415 hp and 466 lb-ft. Here, B&B owner Bob Oster's skilled hands put our 383 through the paces. The next few pulls saw the engine make more power each time, as the rings seated and compression improved. For the fourth pull, the distributor was given the "Jersey twist" all the way up to 38 degrees and we yielded the numbers that would prove to be the best of the day: 425.8 horses and 473.8 lb-ft. That's some awesome torque, and though we couldn't run this particular dyno below 3,600 rpm (near the torque peak), we'll bet the grunt starts way down there.
Like we've been saying all along, the bottom line in this build is our dollar-to-horsepower quotient, so let's figure the denominator. Rahway, New Jersey-based B&B Performance Machine set aside a full day for us to use the shop's SuperFlow SF-901 engine dyno, so one lovely morning in early May, this author, along with editor-in-chief Jim Campisano and longtime Primedia contributor (and carb whiz) Dan Foley, showed up at B&B for a day of testing, tuning, and attempting to eclipse what others may dare not try: beating the crate-engine big dogs at their own game, and doing so for a fraction of the price.So there's the power, folks-425 is just about what we'd hoped to end up with, and over 473 lb-ft is sure to smoke hides of whatever ride this engine ends up in. Now that the dust has settled, the last thing left to address is the money we've spent and how it compares to what we could have shelled out had we not chosen to "build our own." Including all tools-along with miscellaneous items like RTV, extra spark plugs, and spare oil filters-the grand total comes to $5,565 for everything we've quoted a price on in each of our three segments (as well as all of our locally acquired parts). But this alone is not a very good measure of success, not only because this cost includes reusable items a typical enthusiast probably already has lying around from an old worn-out small-block, but because such an overall price quote lacks a benchmark for comparison
So there's the power, folks--425 is just about what we'd hoped to end up with, and over 473 lb-ft is sure to smoke hides of whatever ride this engine ends up in. Now that the dust has settled, the last thing left to address is the money we've spent and how it compares to what we could have shelled out had we not chosen to "build our own." Including all tools--along with miscellaneous items like RTV, extra spark plugs, and spare oil filters--the grand total comes to $5,565 for everything we've quoted a price on in each of our three segments (as well as all of our locally acquired parts). But this alone is not a very good measure of success, not only because this cost includes reusable items a typical enthusiast probably already has lying around from an old worn-out small-block, but because such an overall price quote lacks a benchmark for comparison.
If you shop around on the crate engine scene, you'll quickly find one particular big name 383-inch mill advertised as making 425 hp-identical in power output to ours, and (as far as we can judge) designed for similar street/strip usage, with a fairly lopey (albeit roller) cam and roughly-comparable cylinder heads. Though exact internals differ from those of our engine, the spec sheets are close enough for government work. This particular engine package goes for about $5,000, and for this price, you get a near-complete motor sans major items like a carb, distributor, and fuel and water pumps. When we figure the cost of our engine as identically equipped as possible, the number we get for our mill is-get this-$3,377, give or take a few bucks!That's quite a savings by any measure, and at under $8.00/horsepower, it's inclusive of all machine work, too. It's still impressive even if you throw our $420 worth of tools back into the equation (which you can use over and over). In our view, this shoestring stroker passes the true litmus test: when going as close to apples-to-apples as humanly possible, we've undercut at least one big dog by about $1,600. Truth be told, we don't have items like a forged crank and rods, but we'll never miss them on our N/A engine. Our meticulous selection of affordable-yet-appropriate parts for our intended application certainly seems to have paid off.
Just think of the possibilities: all that money saved can go toward family pet vaccinations, next month's Home Depot credit card bill, or enough Heineken to last an entire frat house a full week or more. Looked at another way, that cash could grab us higher-flowing ported heads, a roller cam, and/or other goodies to put us well ahead of the competition on the power front (we'll keep you updated on any future upgrades we might choose for this mill). Whatever your take, one thing is for sure: Building an engine yourself is fun and makes the end product all the more satisfying. And that, friends, is one thing that nobody can put a price tag on.