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408 LQ9 Budget Engine Build - Finance-Friendly 408, Part 2

Buttoning Up Our Garage-Built LS Stroker And Heading To The Dyno With Hopes Of Unleashing 600+ Horsepower

Chris Werner Sep 1, 2009

Tough times have forced many to pinch pennies, and enthusiasts have not been immune. But a new awareness of the value of a dollar doesn't dictate a death sentence for the hobby we know and love; it just means one must be all the more mindful of prices when shopping for go-fast goodies.

For example, when you're looking at shelling out a lot of dough for a hi-po engine, you want to be darn sure you'll get a good return on your investment. Fortunately, many respectable engine builders offer good deals on assembled LS mills, and this trend has clearly been helped by the falling prices of some of the parts that go into them. But with smart component shopping and some know-how, the motivated DIYer can put together his or her own motor and save even more-and, hopefully, have a fun and rewarding engine build experience in the process.


Last issue, the School of Automotive Machinists (Houston, TX) machined our 6.0L LQ9 iron block, honing the bore out to 4.030-in. as well as line honing the main bores and resurfacing the decks. We then stuffed in our all-forged rotating assembly, which consists of 2618 aluminum Wiseco pistons pinned to 4340 steel connecting rods from K1 Technologies. The steel crankshaft, also K1, delivers a 4.000-inch throw to allow this mill to squeeze out 408 cubes of LS fury. With the short-block completed, the next area to address is the valvetrain.

In this issue, we continue our quest for all-out LS horsepower for minimum investment. We're not cheating the bottom line by incorporating any used components, either-everything down to the engine block is all-new. An N/A build has been chosen in order to forego additional monies spent for power adders, not to mention the unrealistic factor of simply turning up the juice or boost for a high horsepower number. And while factory bottom ends are sturdy enough to reliably supply plenty of tire-shredding torque, extra cubic inches over what a stock-stroke crank can supply opens up the potential for many more ponies, so a stroker it is.

Having put together our short-block in our August installment, it's time to finish off the assembly, so follow along in the photo captions to get the gist of how it's done.

Editor's Note: In the interest of saving space, some details were skipped over during this build. For a more step-by-step breakdown, see Werner's "My First Stroker" series in GMHTP August, September, and November '06. You may also consult his book, "How to Rebuild GM LS-Series Engines" available from www.cartechbooks.com as well as your local book retailer or GM dealer.

Dollars And Dyno Graphs
Stroker Parts And Price Breakdown
Short-Block Parts Subtotal:

Long-Block Parts Total (Includes Short-Block Parts):

Machine Work Total:

Total Additional Parts To Complete "Crate Engine":

Tools & Miscellaneous Total:

Before getting to our results, an analysis of how much it took to put together our 408 is in order. Check out the accompanying table for a full breakdown, noting that when possible, all prices quoted here and elsewhere in this story are those of major retailers and have been rounded to the nearest dollar. Some prices of new-to-the-market components were quoted from the manufacturer so are a tad high, and a few-notably, rotating assembly components-have been adjusted to reflect prices you can find on the web (as opposed to MSRP) so may differ from what you saw in Part 1. Finally, prices not directly available are estimated, as is the case with machine shop labor. Since readers attempting to duplicate this build may already have a donor LS to reuse parts from, we've done our best to classify all parts into "long-block" (minimum for build) and "crate engine" (soup to nuts) distinctions. Even so, the category breakdowns are not exact-for example, you could not get away with reusing a stock F-body intake with rectangular-port heads, making the L76 mandatory for an F-car application-but we feel this breakdown best matches how engine builders market their assemblies.


A lifter (aka tappet) is slid into the #1 intake position and Summit's Magnetic Base and Dial Indicator Kit is used to get a zero reading with the lifter on the lobe's base circle. The crank is turned: according to the cam card, the intake should hit 0.006 tappet lift at 36 degrees before TDC and again at 80 degrees after BDC, and by noting the degree wheel reading at 0.050 both ways and dividing by two, we should come up with a 111 degree intake center line. We go through the process and it all checks out, so we're set!

As one can see from the accompanying table, it took just over $6,900 in parts and another $925 in (estimated) machine work costs to put this mill together, bringing total investment to $7,800 and change for the build if one assumes a donor F-body LS1 is available to supply the likes of engine sensors and covers (figure another $2,500 or so if not). The grand total figure of $10,353, then, represents a complete "crate engine" that could be built and dropped straight into an F-body engine bay. Of course, if you're going this route, it's likely you already had headers/exhaust/intake and some driveline upgrades necessary to handle the power, but that's all beyond the scope of this story anyhow. Take a look around at comparable engines from respected builders; while absolute apples-to-apples comparisons are virtually impossible, we think you'll agree a decent amount of dough was saved by choosing our own parts and assembling the engine at home. The downside is the extra time and care that must be taken, of course, but most who go this route will find having done their own engine assembly most rewarding indeed.

For testing, the 408 was brought out to southeastern-PA-based RaceKrafters, a top-notch shop well known for late-model high-performance, and one which we called on in the past during GMHTP's 355 LT1 build (see the recent "Top End" series) as well as various TPI stories. Whether you're talking about a mild street engine or a 7-second drag race mill, RaceKrafters offers everything from full engine machining and assembly services to both engine and chassis dyno testing and tuning. These guys quite literally do it all-and damn well, we might add.

Once the RaceKrafters crew got our mill mounted onto their dyno, they broke it in and were successfully making over 550 hp when-uh-oh-the engine started making some strange noises. Fortunately, our LS was in good hands ... in the exercise of utmost caution, a disassembly was undertaken, which revealed damaged main bearings that appeared to have been set on the tight side of clearance (perhaps this author should have put more credence in his Plastigage readings-see Part 1 of this build!). With the necessary fixes and adjustments made, the 408 was reassembled and dyno testing resumed. The skilled hands of RaceKrafters President Bob Wise put much time into perfecting a tune for us, and when all was said and done, 554 horsepower and 508.5 lb-ft were the result.

That's a lot of output, especially considering the money put into this finance-friendly stroker; but alas, it falls somewhat short of expectations. It would stand to reason that a higher-flowing intake manifold could add a bunch more ponies, and the 1.75-inch headers used in this test are almost certainly holding us back. Never ones to back down from a challenge, we've got some tricks waiting in the wings to remedy these shortcomings (while still keeping with the budget theme), so watch the next issue of GMHTP-the dyno flogging has only just begun!


Scoggin-Dickey Parts Center
Lubbock, TX 79424
SLP Performance Parts
Toms River, NJ 08755
Comp Cams
Memphis, TN 38118
Royal Purple
Porter, TX 77365
Memphis, TN 38118
LRB Performance Machine Company
Franklin, NJ 07416
RaceKrafters Automotive Machine
Lancaster, PA 17601
Memphis, TN 38118
Lakewood, NJ 08701
www.manleyperformance .com
BRP Hot Rods
Cumming, GA 30040



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