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A Slice of WedgeNelson Racing Engines Returns to the Engine Masters Challenge with a 440 Mopar From the February, 2009 issue of Popular Hot Rodding By Scott Parkhurst
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In last year's Engine Masters Challenge, we introduced readers to young Tom Nelson. The So Cal engine shop owner was crafting his entry to make a strong statement, and a solid seventh place finish did just that. When we announced the parameters for the big-block Challenge, Tom Nelson was again one of the first to step up and commit to an entry. While we know Tom's focus is on serious street small-blocks, many with twin-turbos (as seen under the hood of Stielow's new "Malitude" '65 Chevelle), Tom is confident in his ability to research and maximize the potential in any engine. In fact, after reviewing the rules for the 2003 Challenge, Nelson felt a 440 Mopar would have several natural design advantages over all the other makes. For these reasons, he is entering the very first Chrysler product he's ever built into the Challenge to face other participants who have literally dedicated their lives to wringing maximum power out of their make of choice. Why the switch in brand loyalty? "I feel the Mopar 440 is best-equipped to compete at this level. The Indy cylinder heads are key, but the rules limitations on valvetrain modifications to factory design or factory replacement parts makes the 440's shaft rocker setup ideal. It's very strong, and the intake ports are sized right and located correctly. One of the main reasons I chose the Chrysler was the big .904-inch diameter factory lifter. I worked all the numbers out, and I should be able to run about 8 degrees more cam duration at .200-inch lift than other makes. This should allow me more bottom end torque without sacrificing anything on the top end. "Compared to a big-block Chevy, which has two different size intake ports from cylinder to cylinder and is limited to stud-mounted rockers for the Challenge, the Mopar is a better call, in my opinion. The Hemi stuff is good too, but it's expensive (by comparison) and may not perform as well in the lower rpm ranges. The Hemi will easily make more upstairs, but I think the 440 will overcome this by making solid power lower in the rpm range. I think I'll make more down low and not sacrifice as much in the upper rpm levels, which will give me a better overall score." Overall score is the key to winning the Engine Masters Challenge, as average power numbers (both torque and horsepower) are added together to determine a final score and, ultimately, a winner. Only power figures in the test rpm range (3,000-6,500) will be counted, so every pony and pound are equally-weighted. Nelson learned that picking up 50 horsepower or foot-pounds down low is better than picking up 15 or 20 horses up high, since the averages are equally weighed in scoring. Tom learned plenty about doing well in the inaugural 2002 Challenge, and he stands as one to watch after finishing so well last year. We invite you to look over Tom's parts selections, and if you're considering a buildup on the popular low-deck stroker version of the Mopar Wedge, here's a super example of how to make it sing with readily-available parts.  Nelson is basing the build...  Nelson is basing the build around an Eagle stroker crankshaft, a stock 400ci low-deck block, and Indy cylinder heads. These proven parts will easily support the power Tom intends to make, and readers who already have a good bottom end should consider following Tom's lead, especially once final power numbers are published. Since the new crank is internally-balanced to zero, Nelson will not have to add weight anywhere once the reciprocating assembly is put together.  The crankshaft will be offset...  The crankshaft will be offset ground, and Nelson explains why. "I bought a new 'blem' crank from Eagle that had been turned .010/.010 on the rod and main bearing surfaces already, and then I offset ground the journals from the Mopar factory dimension (2.375-inch) to a big-block Chevy size (2.2-inch). This will result in a 3.905-inch stroke."For readers with intentions of custom machining their cranks, or for those looking to save a few bucks on a new crank, the "blem" angle is a hot tip. Often, manufacturers have parts like this available, but you have to ask.  Obviously, the Indy heads...  Obviously, the Indy heads are key, and these are based on Indy's 440-1 casting. Designed for use with offset rockers, the heads ship without the traditional pushrod bulge into the intake port from the side. This makes for a much wider intake port, and a much straighter shot at the valve for the intake air/fuel charge. It's apparent how much material got moved around in Nelson's quest to find the proper amount of flow while maintaining terrific velocity.  The intake ports were raised...  The intake ports were raised as much as possible while maintaining adequate gasket clearance for a good seal, and the floors were filled to create optimal port volume and shape. If you port heads, note this overall port shape and compare it with others you'll see in Challenge entries- this should be the general shape you're after.  The stainless valves are from...  The stainless valves are from SI, and measure .100-inch longer than stock, with valve head diameters of 2.145-inch on the intake side and 1.81-inch on the exhausts. The Indy chambers only needed a minor amount of work to achieve the size and shape Nelson was after. Note the unshrouding around the intake valve, and the encouraging of a kidney bean or heart shape to the chamber. Nelson has trusted Richard Reymer (of West Coast Cylinder Head) to work over his castings. The target flow numbers are 365 cfm on the intake side and 240 cfm on the exhaust side, when flowed at 28 inches of water with the valve at .600-inch lift.  The connecting rods are Eagle...  The connecting rods are Eagle parts, designed for big-block Chevy engines but perfectly at home in this Mopar. The rod center-to-center dimension is 6.800-inch, and the rods carry Eagle PN CRS6800-S. They feature Eagle/ARP 7/16-inch bolts, a .990-inch (stock Chevy) pin diameter, and weigh in at 811 grams.  The pistons are JE products,...  The pistons are JE products, and don't let the big domes fool you. While these are not the pistons headed in to the Challenge entry, they're a very similar design, minus the high domes. The pistons Nelson has chosen are flat-top forgings, and come ready to accept the .990-inch Chevy pin (at 2.930-inch length), and they'll see some work on the bench before being put to work under the heads. "I'm going to have lateral gas ports drilled, and I'll run standard-tension D-wall oil rings, which will be Calico coated. I'm not going to mess with the low tension rings like I did last year. Without a vacuum pump in place to help them seal, we saw some oil in the chambers when we tore last year's engine down. We don't feel the gains in minimizing ring friction are worth the potential losses in ring seal, so we'll up the tension a bit to ensure no blow-by."  The top and second rings are...  The top and second rings are diamond lapped Total Seal parts, with a thickness of .0415-inch. It's a traditional "gapped" ring, and Nelson will run minimal gaps in the neighborhood of .014-inch for the top ring and .018-inch for the second ring. After using just about every ring out there, we feel its noteworthy Tom decided to go with a top quality traditional ring design, and those considering more radical or less durable rings for their own engines should take note. The diamond lapped rings are precision crafted to seal perfectly to both the cylinder wall and the piston groove, and they are thick enough to offer excellent durability. For those questioning the ring choices of past Engine Masters Challenge engines as not being truly streetable, here's a move in the right direction.  The engine bearings are "mostly"...  The engine bearings are "mostly" Clevite 77 products with Calico's coatings. The single exceptions are the camshaft bearings, where Tom has chosen Durabond parts. These too are treated with friction reduction coatings. Are you getting the message about performance coatings yet? They work on many levels for different purposes all throughout a performance engine, and if you've never run them before, you're giving up some free horsepower. No other changes are required to see the benefits of performance coatings.  Nelson's research into the...  Nelson's research into the big-block Mopar wedge led him straight to Milodon for all his oiling system needs. The matched pan, pump, swinging pickup, oil pump drive shaft, and remote filter housing have been mainstays in Milodon's product line for many years. The external oil pump on big Mopars means external lines are a regular part of life, and will be permitted for the Challenge. While we made a huge point to eliminate external drainback lines, we did permit engines with external pumps (like the big Mopars, and also Buicks) to plumb their pressure lines externally right from the pump.  The Milodon oil pan is engineered...  The Milodon oil pan is engineered with windage trays and crank scrapers, which require no mods to install. Naturally, all Milodon's Mopar oiling system products are designed to work as a system, so everything should go together easily. If you're ready to step up the oiling system under your 383-440, this is an established, effective, and well-engineered solution.  Feeding fuel to the heads...  Feeding fuel to the heads is a job for an Indy-crafted intake manifold, although Nelson is still unsure if he'll be bringing a Dominator-topped version or a 4150-fed casting. Both will be tested, and Tom expects both will have distinct characteristics. With a wide range of induction ideas, testing and research are the only way this decision can be made.  The carb metering the fuel...  The carb metering the fuel is, obviously, undecided at this time, but Nelson assures us it will be a Carb Shop unit. This particular carb is representative of what Tom will test, as this particular mixer began life as a Holley 1050 Dominator, and was then put through the Carb Shop's proven performance gauntlet (in this case, their "Stage V" treatment) so everything on the carb that can be adjustable is. With so many tuning variables, the elusive killer tune up is most certainly in there somewhere, it's "simply" up to Nelson to find it. "This carb probably flows somewhere around 1,250 cfm now, and I'm thinking this is the right one for the Challenge. Testing will tell for sure, but I'm confident I can run the big carb and adjust everything around it to perform well on this engine." Considering there's only 470 inches to feed, and the redline rpm of 6,500 isn't truly high, tuning this carb to its full potential is a challenge unto itself. Nelson will also experiment with HVH Super Sucker carb spacers.  The ignition system is all...  The ignition system is all MSD products, from the 7AL-2 control box (MSD PN 7220), to the 8.5mm wires (MSD PN 31199) to the billet distributor (MSD PN 8545) and finally to the coil. Time and experience led Nelson to MSD, and he trusts the products completely.  The camshaft is key to a good...  The camshaft is key to a good finish, and Nelson has chosen to consult with Crower for the right part. After seeing Crower's strong finish in last year's competition, we can understand Nelson's choice, but does the fact that the competitive Crowers are once again entered in the 2003 Challenge make a difference to Tom? Apparently not, as he has complete faith in Crower's advice, and Nelson has offered plenty of input toward his own profile grind. "This cam is extremely fast; even faster than some roller profiles. It's at 260 degrees at .050-inch of lift, and total duration is only 290. That's really snapping the valve open quickly, which I feel is key." The specs on the grind Nelson will begin testing with are .575-inch lift with the aforementioned 290 degrees of duration, .552-inch of lift on the exhaust side (with 282 total degrees of duration, and an equally-aggressive 262 degrees at .050-inch). The lobe centerline is at 104 degrees. The lifters will be Crower's solid flat tappets.  The rockers are also by Indy...  The rockers are also by Indy cylinder head, and Tom is planning to run our Challenge-maximum 1.7:1 ratio rockers on the intake side, and a gentler 1.5:1 rocker on the exhaust. Naturally, a good spring will be necessary to deal with the aggressive cam and rocker ratio combination. Valve springs will have to be tough, but not unstreetable, and check in with 140 lbs on the seat and 360 lbs of pressure at full open.  Connecting the custom cam...  Connecting the custom cam to the custom crank is a Jesel beltdrive. It carries PN KBD 35000 and stands as a well-designed part requiring no mods to install. The real reason it was chosen was to expedite camshaft timing adjustments on the dyno, and Nelson intends to use it to its full potential. "Running the beltdrive will make experimenting with cam advance so much easier. I intend to push the advance to 98 degrees to find more average power, and the beltdrive will allow me to make near five cam advance changes in as little as 30 minutes of dyno time. This ability is absolutely essential in a competition like this."  Cooling this beast is another...  Cooling this beast is another area Tom has researched, and again Indy came up with the solution. They offer this reverse cooling adapter plate, which fits our rules (by bolting up in the stock location) and directing coolant first to the heads, and then the block. This is a proven power tip, and it doesn't get much easier than bolting up an adapter and adding an electric pump. It's parts like these we expect to make a difference in the Challenge, and also on the street.  Some of Nelson's other parts...  Some of Nelson's other parts choices include an ACCEL air filter...  BHJ balancer, a TCI flexplate,...  BHJ balancer, a TCI flexplate, and ARP hardware throughout.  Covering the rockers is a...  Covering the rockers is a job for matching Indy Cylinder Head valve covers. These cast beauties are more than just pretty. Since they're cast aluminum (like the heads), they'll expand and contract with heat at the same rate, which should mean no leaks.  Nelson's theories are his...  Nelson's theories are his own, and his philosophies are evolving with the Challenge itself. He explains:"The dyno will tell me where to go. It'll either be awesome everywhere from the bottom through the mid-range, then taper off at the top, or, it'll be great down low and really scream at the top, but might be a little lazy in the middle. Since this is the first Mopar wedge I've designed, I'll need some dyno time to really dial it in. I still feel it has an advantage over the other makes."What does he feel it'll take to win the Engine Masters Challenge?"I think it'll take at least 775 peak horsepower and at least 700 foot-pounds of torque to win. I intend to be a serious contender by playing with the averages once the engine is running. I should be able to maintain 675-plus foot-pounds and 750-plus horsepower throughout the rpm range, which should make for some solid averages. If all goes as planned, I'll have a very high final score, and I could win this deal."Time will tell, and we'll see how Tom finishes on dyno day! Tune in next month for another inside look at an Engine Masters Challenge competitor!
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Nelson Racing Engines
9318 Oso Ave.
Chattsworth
CA
91311
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