We've had some time to look over the entries for the Engine Masters Challenge, and there was only one Pontiac-based powerplant entered. Byron McElfresh of Pacific, Missouri, has been playing with 350-cube Ponchos for several years, since they are abundant, affordable, and unwanted. As we've said (and recommended) before, Pontiacs of less than 389 cubes don't have a tremendous following, simply due to the increased power potential in the larger-cube versions.
Remember, Pontiac never made a "small-" or "big-" block--they used the same block dimensions from the small 326 all the way up to the 455. This "mid-block" design was a stout one--as was proven over and over again on the streets of America throughout the '60s and '70s. The Pontiac design served as the basis for the small-block Chevy (note the port configuration and stud-mounted rockers), and like its GM cousin, possessed tremendous potential. Only a few modifications must be addressed to make the bigger-inch (400-plus-cube) Pontiac V-8 a real street contender, and enthusiasts have always gravitated toward the larger-displacement engines.
This little 350-based motor will need more help! Luckily, Byron's experience with these powerplants will help, and he has some very definite ideas about what he's after. Since their introduction, Edelbrock's aluminum Pontiac cylinder heads have opened doors for Poncho fans and while they were designed to feed healthy big-displacement Pontiacs out-of-the-box, Byron's worked-over 350 can also take advantage of their engineering. Remember that Byron is not a professional engine builder. He's a hobbyist like so many of you fine readers. He's drawing purely from his experience and is on a tight budget. Many of his parts are factory items or aftermarket copies of factory items. This may be the closest to a factory engine we'll have in the Challenge, but that remains to be seen, as well.
So, with a solid game plan based on past experience and much math, Byron is heading into the Engine Masters Challenge as the sole representative of the Pontiac faithful. Can his design mods compete with the Chevy and Ford entries? Can this little Indian motor run with the big dogs on dyno day? Only time will tell, but let's take a look over his shoulder and see his parts choices. Compare these parts with the others we've shown you in previous buildups and calculate his odds of winning yourself. We'll certainly be keeping an eye on this one and maybe the competition should, too.
Notching the top of the bores is not an unusual way to accomplish this; many 350 Pontiacs were notched at the factory to clear larger intake valves. Byron will have to increase the size of the intake notch and add a notch to the exhaust side to accommodate the larger valves used in Edelbrock's head. | 
He uses a gasket as a template to mark the areas to be ground. Byron's overbore and cleanup will leave a 3.935-inch final bore size. The factory bore size was 3.880 inches. | 
The cast nodular crankshaft is also a factory Pontiac part with a 3.75-inch stroke. Mods will include a mild 10/10 cleanup and careful chamfering of the oil holes. |
The connecting rods are from C.A.T. Power parts in factory 6.625-inch lengths. This H-beam design rod is lighter than the factory part, and Byron has had them bushed for full-floating pins. They are affordable and warrantied--that's a tough deal to beat. Byron feels no need to run a longer-than-stock connecting rod, as the factory 6.625-inch length is much longer than a comparably-cubed small-block Chevy with factory 5.7-inch or even popular aftermarket 6-inch rods. Note the ARP rod bolts for insurance. | 
The pistons are from Venolia; Byron chose them because he's had good luck with them in the past, and they were readily available for his oddball bore size. The ring location has been raised, and the block will be machined to be even with the piston tops at TDC, commonly known as zero-decking the block. The valve reliefs will have to be milled in the piston tops, and once the machining is done they will be coated with a thermal barrier, as well. The pin is a small-block Chevy diameter, but is slightly shorter to save weight. The Chevy pin already offers weight savings over the factory Pontiac part. | 
A tool Byron wanted us to mention was this Tavia aluminum ring compressor. Tools like this have been around for awhile, and if you build engines with similar bores repeatedly, it's good investment. Byron says, "It sure beats wrestling with adjustable ring compressors. I've broken too many rings wrestling with those things. These tools make the job a snap." |
The piston rings are from Total Seal and include a thin .043-thickness top "file-to-fit" ring, a 1/16-inch gapless second ring, and a traditional 3/16-inch-thick oil ring. This particular ring arrangement has worked well on past Pontiacs Byron has built, and he's a believer in this ring arrangement. | 
The camshaft will be a COMP Cams hydraulic roller. Byron has decided to start his tuning with a .586-inch lift, 286-degree duration cam with 110-degree lobe centers. "Once it's running, I'll probably try several different profiles, but I feel this is a good place to start." | 
The hydraulic roller lifters will be Crane parts. "I like the oil groove location--it's perfect for the Pontiac. The quality is excellent. Crane had these in stock, and I've never had a problem with them." |
The timing chain is a proven Cloyes double-roller piece. "It's affordable and dependable." | 
The heads will be outfitted with Harland Sharp roller rockers in a 1.65:1 ratio. This ratio is more than the 1.6:1 ratio Chevy guys are allowed, since many Pontiacs shipped with 1.65:1 rockers. Our Engine Masters Challenge rules allow for ratios greater than 1.6:1 only if the factory engines shipped with more. Will it prove to be an advantage? Only time will tell. | 
One of the design elements Pontiac enthusiasts must address is the rear main seal. The factory motors shipped with rope seals, and while they worked just fine from Pontiac, enthusiasts have never been truly happy with them. Luckily, B.O.P. Engineering (920-674-2522) has developed a new rear main seal that cures these ills. Manufactured from Viton, it is an all new part that works great the first time. |
The front of the crank will see this BHJ balancer. "I like the BHJ part because it's engineered for use with factory Pontiac pulleys. I've tried other balancers, and once you buy them, you have to go back and buy new pulleys, too. This makes it easy, and it's a great quality part." | 
The intake is an Edelbrock Performer RPM--a dual-plane design with large ports. Byron feels this is the best call to make for the Challenge. "I like the bottom end this design can add, and the ports are large enough to feed this small engine. The intake was designed for larger engines, so this should be close to perfect out of the box. The ports will be matched, and I may cut the divider down about 1/2 inch. Certainly I'll trim it down between the secondaries, at least. | 
The carb will be Holley 4150 in either 750 or 850 cfm. Again, experimentation will define what works best. |
Headers are by Indian Adventures and are a relatively new product. "I run an early Firebird at the drags, and these are the best fitting, best-performing headers I can find. The primaries are a little larger than I'd like (2-inch compared to 1 3/4-inch), but I like the long primary tubes. There are no commercially available headers for my car with nice, long 1 3/4-inch diameter primary tubes." | 
Ignition is all MSD. "I've used their parts forever, and they've never failed me. It's a reliable, affordable, adjustable unit. I have several different bushings and springs I'll be using to fine-tune the advance curve." | 
The key to making this engine a player is in the heads. "The Edelbrock aluminum head is great. I'll plumb the rear of each head with a coolant line to equalize the flow to the rear of the heads. Cylinders 7 and 8 run hotter in Pontiacs, and there's power to be found by plumbing the heads this way." |
"I found several of these parts on eBay, and the others were things I had or knew were available. I've gotten some great deals on some of this stuff, just because I knew what I was looking for on the Internet. While you're researching and shopping, the Internet is a great source of information, and there are some great deals out there. The most important thing is knowing what you're looking for. This is a budget engine, and it's a Pontiac, so having specific part numbers and measurements is really important when shopping online." Thanks Byron and good luck on dyno day! | | |