Setting the Stage
Bruce Kent builds a Buick for the Engine Masters Challenge
From the February, 2009 issue of Popular Hot Rodding
By Scott Parkhurst
When we first announced the parameters and rules for the 2003 Engine Masters Challenge, the rumblings and rumors about the best-possible combinations began immediately. While the overwhelming number of bets were being placed on the broad-based Chevy market, we heard about the benefits of the Mopar 440 and the Hemi, too. There were a few very knowledgable gearheads I spoke with at the Performance Racing Industry (PRI) show who didn't hesitate for a moment after looking over the rules, and the first words out of their mouths were "Look out for the Buicks."
Long known for making insane torque at low rpm levels in bone-stock shape, big Buick V-8s have long been a mainstay of the underground street racer. Boasting 500 ft.-lbs. of torque with the capability to ingest gobs of nitrous, the stock Stage 1 Buick 455 was the perfect weapon for the street digs. In modified form, we've seen big Buicks dive deep into the 9-second zone in street trim, and we featured an 800-horse twin-blown Buick on the cover of our September '99 issue. It remains a favorite cover around here, and the man behind that engine is back for more; namely the Engine Masters Challenge.
Bruce Kent of San Dimas, CA, is a well-known West Coast Buick enthusiast who always shows up with nice cars, a great laid-back attitude, and a kind demeanor. He's the nicest guy in the world as long as you're not staging next to him at the strip. The Buicks he builds and pilots are always deadly quick, and it's not just local hype. He and partner Dave Benisek have owned their class of choice (called Street Eliminator) at the Buick-only GS Nationals (held in Bowling Green, KY) for three of the last four years. It would have been a 4-year sweep, save for a single faulty plug wire that cost them the final round. Kent drives Dave Benisek's '74 Buick Apollo (an X-body car, like a Chevy Nova) powered by a Kent-built 470-inch Buick engine. The car is limited to 10-inch tires, and has run a best elapsed time of 9.96 at 135 mph. While a 9-second all-motor Nova-type drag car may not sound too fast to the regular readers of this mag, consider the minimum weight in the class is 3,800 lbs. Suddenly that 9-second run is looking pretty good, isn't it?
Suffice to say Bruce Kent knows how to make serious Buick horsepower, and he does it all in addition to running his own industrial mold making business. The racy Buicks are "just a hobby," but obviously it's a hobby Bruce Kent takes very seriously.
For the Engine Masters Challenge, Kent wanted to team up with the Buick parts source at TA Performance, and work his magic on the most aggressive aftermarket Buick parts offered. The teaming of Kent and TA Performance offers Buick enthusiasts nationwide a good look at the engine of their dreams: a max-effort 92-octane all-motor 470-inch monster that will crank out nearly 800 horses and make broad power from 3,000-6,500 rpm.
We wanted to show readers this engine for several reasons, and we feel it typified everything we love about the Engine Masters Challenge. It stands as a well-researched powerplant with all intentions of setting the bar for Buick enthusiasts, and all of its parts can be readily obtained or easily duplicated. It would require no mods to bolt right into any 68-72 Buick A-body, and it would become the terror of many towns across America if that same car could put all the power to the pavement.
So, follow along as we document what may be the premier Buick pump gas street engine in the country. Since it's based on a stock block/stock crank combination, it should be relatively easy to duplicate and of course, all the parts are out there if you want them. Sure, you'll have to find a cylinder head expert capable of crafting the ports to flow what Bruce Kent's do, but the flow numbers are here for you to shoot for. The bar is set, and all we've got left to wait for are the competition dyno numbers from this big Buick. Naturally, there are 49 other builders looking to shoot down Bruce and his Stage III masterpiece, but after reading the story, you'll see what a big job that's gonna be. Let's jump into it!
Bruce is basing the build...
Bruce is basing the build on a stock '72-era factory Buick 455 block and crank. Naturally, the parts have been checked for cracks, cleaned, and detailed. A major consideration for big-inch Buicks is in the lifter bores and the oiling system. Aggressive camshaft profiles can break the lifter bore castings, and the oiling system was not up to par with the needs of high rpm performance.
To alleviate any concerns...
To alleviate any concerns about the lifter bores, Bruce epoxied in a brace from the front of the lifter valley all the way to the rear. While lifter bore support was the primary reason, Kent also carefully molded the epoxy to form oil drainback routes from the heads to the pan (arrows). This keeps the oil off the spinning reciprocating assembly. There are aftermarket bolt-in braces available to assist the lifter bores, but they do not address oil drainback at all. With oil control being a major issue on all performance engines, but especially on Buicks, these mods are critical.
The block has been filled...
The block has been filled with Hard-Blok to the base of the water pump holes to add bottom-end rigidity. Kent says street 455s can live with this mod, but he'd have probably used a bit less filler and allowed for a greater quantity of water for a dedicated street engine.
You'll also note the huge...
You'll also note the huge bottom-end girdle, which came from TA Performance. This is standard fare on Buicks making over 600 horses, and keeps the two-bolt main bearings stable under pressure. The block oil passages have been enlarged from the primary feed port up to the cam/lifter galley. Also, the oil passage from the main galley manifold to the main bearings has been cleaned out and smoothed as much as possible to aid lubricant flow.
The block has been bored .0380-inch...
The block has been bored .0380-inch for a total bore diameter of 4.350. The factory '72 nodular iron 455 crank has been ground to a 3.942-inch stroke before being Nitrided for surface hardness.
Together, these bore and stroke...
Together, these bore and stroke dimensions add up to a 469-inch total displacement; just below our 470-inch maximum for the Engine Masters Challenge.
The crank has had the rod...
The crank has had the rod journals turned to 2.2-inch diameters to accept Chevy connecting rods. This opens up rod choices tremendously, and Kent has chosen Eagle H-beam rods in 7.1-inch lengths. The big ends of the rods have to be machined slightly thinner in width to fit on the Buick crank, but it's not difficult and does not affect the integrity of the rod whatsoever. The rods weigh 852 grams and carry a part designation for Chrysler 426/440 engines using Chevy rod dimensions (PN CRS7100C3D).
The pistons are from CP, and...
The pistons are from CP, and weigh 547 grams. They have the necessary big-block Chevy pin diameter of .990-inch, and pin length is 2.75-inches.
These pistons will be treated...
These pistons will be treated to Tech Line coatings, along with the valves and combustion chambers. Bruce is handling the applications of the coatings himself, once the final piston fitting is complete.
The rings are Total Seal gapless...
The rings are Total Seal gapless units with 2-piece top rings that fit together to form a gapless seal. Testing has shown this to be worth power, and street enthusiasts should take note.
Bruce will be testing several...
Bruce will be testing several camshafts, and he shared the smallest and largest cam dimensions with us to show readers the range he's looking at. None of these dimensions are final, of course, but this is as much camshaft info as we could share at this point in time. Kent has several Comp Cams in tow, with the smallest checking in at .617/.607-inch lift (intake/exhaust), with 248/252 degrees of duration at .050-inch lift and 114-degree lobe separation. The largest cam he's planning on measures out at .634/.607-inch lift, with 258/262 degrees of duration at .050-inch of lift and 112-degrees of lobe separation. The lifters are standard Comp Cams High Tech Lite (HTL) solid flat tappets, carrying PN 807-16 and maintaining Buick's factory lifter diameter of .842-inch.
The pushrods will be from...
The pushrods will be from Manton, while the valve springs will be Isky parts measuring 150 lbs of seat pressure and 420 pounds at full open. The rockers are from TA Performance, and are manufactured by T&D exclusively for TA. They are a stock replacement setup with 1.7:1 ratio (the max ratio allowed for the Challenge) on the intake side, and 1.65:1 rocker ratio on the exhausts.
The cylinder heads are TA...
The cylinder heads are TA Performance Stage III castings, which began life as factory Stage II designs before being refined by TA. The results are tremendous, with Buick enthusiasts able to get great performance from a bolt-on head without modifications. Shown is the combustion chamber on the original Stage III casting and the modified chamber.
This is what Kent will run...
This is what Kent will run on the Challenge motor. Final compression ratio will check in at about 12.75:1. After all the surfaces get coated, it should present no detonation problems for the 92-octane gas we'll be using in the Challenge.
These heads were carefully...
These heads were carefully ported to deliver 385 cfm of airflow at .700-lift at 28 inches of water on the flow bench. These are the "as-cast" intake and exhaust ports of the TA Stage III heads.
The exhaust side breathes...
The exhaust side breathes 295 cfm at the same .700-inch lift point and at the same water depression.
These heads were carefully...
These heads were carefully ported to deliver 385 cfm of airflow at .700-lift at 28 inches of water on the flow bench.
A look at Bruce Kent's hand-finished...
A look at Bruce Kent's hand-finished ports.
The intake manifold is also...
The intake manifold is also from TA Performance, and is a single-plane design.
It will be hand-finished by...
It will be hand-finished by Bruce to work with the cylinder heads, and he'll test several carb spacers to find the best-possible combination.
The valves are from Manley...
The valves are from Manley and diameters are 2.225-inch on the intake side, and 1.80-inch for the exhaust. They will be coated with a heat barrier coating from Tech Line Coatings.
The headers are out-of-the-box...
The headers are out-of-the-box TA Performance pipes for '68-'72 Skylark and GS. They carry PN TA2014SCHA and boast a 2.150-inch primary tube with 3.5-inch diameter collectors. Bruce is planning on testing several mufflers, but he's angling toward MagnaFlow parts.
The ignition system is mostly...
The ignition system is mostly MSD equipment. The distributor carries MSD PN 8517 with a 6AL box. The spark plugs will be Denso parts, and Kent will test several heat ranges to get the right plug for the job. One of the new Plasma Boost ignition boxes was added on for additional zap.
The oil filter is from System...
The oil filter is from System One, and it will be filled with Royal Purple race oil for the Challenge.
The oil pump will be hand-built...
The oil pump will be hand-built by Kent, and he knows how to pay attention to the critical clearances inside to ensure adequate pressure and volume to the big Buick.
Another critical oil system...
Another critical oil system component is the oil pan. This part, made by Stef's, is designed to fit under a stock Buick chassis and will aid in oil control. Kent will use Fuel Safe foam, designed to eliminate sloshing inside gasoline fuel cells, to control windage. While we've not heard of this method previously, we intend to ask Fuel Safe how they feel about it. It sure seems like a budget way to thoroughly control oil, but is it a long-term mod? We doubt it, but it should be fine for the Challenge testing.
Even more oil control? You...
Even more oil control? You bet. One of the problems with building a hi-po Buick is how you're committed to running the unique cast front timing cover. While ancient factory parts suffer from the ravages of time and can warp, crack, and prove unreliable, TA Performance is now casting new parts to fill the void.
Since Buicks have external...
Since Buicks have external oil pumps, TA refined their casting a bit in this critical area. Buick fans should all buy one of these covers when rebuilding an engine simply for the peace of mind that comes with replacing a questionable casting with a new one.
Other critical details include...
Other critical details include an ATI balancer...
Really trick fabricated valve...
Really trick fabricated valve covers from Unique Aluminum Products.
The block will be loaded with...
The block will be loaded with coated bearings, including Childs and Albert main and rod bearings.
The fully-grooved cam bearings...
The fully-grooved cam bearings are also coated, and come from TA Performance. Coatings are now a cash-paying contingency category in our Challenge, and the benefits of these new technologies are sure to show up in the power figures. Kent relied on Calico Coatings to cover his bearings.
The engine will be topped...
The engine will be topped with either a Holley or Demon carb (both will be tested) and incoming air will be filtered through a Rush Filter by Barry Grant in 14x3-inch dimensions. Filter size is specified by the rules posted at www.enginemasters.com. When asked about how he feels the Buick will finish in the standings, Kent was humble. Since we know Bruce, we also know he'd much rather understate his chances on the conservative side and let the engine do the talking. Time will tell.
"I know it'll make much more...
"I know it'll make much more than 700 at peak and have strong average numbers to score well in the Challenge. The cam is pretty aggressive, and with a slightly milder cam this would be a great street engine. The valvesprings are not huge, and the test rpm range is low. I wanted to build and test with a mule shortblock the way Joe Sherman did last year, and then bring my fresh stuff to the Challenge, but I found a crack in my spare block and I can't test with it now. So, this is it; this is my only engine. I hope it does well, and I hope the Buick fans out there see how much potential there is in a stock block/stock crank combination like this. It takes more time and effort than a Chevy would, and probably more money, too." We at PHR know it's cool to have something different, and if it happens to be a near-800 horse Buick pump gas engine, we're on board! Thanks Bruce, and we wish you the best of luck in the Engine Masters Challenge!
16167 N. 81st St.
SYSTEM ONE FILTRATION
PO Box 1907, Dept. PHR
Eagle Specialty Products
ROYAL PURPLE OIL
One Royal Purple Ln., Dept. PHR
3406 Democrat Rd., Dept. PHR
UNIQUE ALUMINUM PRODUCTS
1507 NW Northwood Dr., Dept. PHR
Holley Performance Products
1801 Russellville Rd.
Bowling Green, KY 42101
20 S. Hale Ave.
Barry Grant Inc.
1450 McDonald Road,
Total Seal Piston Rings