Curing Common Distributor Ills
Bringing HEI ease and performance to the 572 crate monster.
Story Jim Moore - Images Randy Borelly and Mike Miller - June 20, 2011 09:00 AM
Here’s what happens when you go a little too long on a solid roller lifter without checking it. They don’t roll too long like this and bad stuff happens fast!
It’s pretty simple. To go fast, you’ve got to make power. To make power, you have to burn fuel. And to go even faster, you have to burn it efficiently and get the most out of every drop.
When the Davis Unified Ignition folks stepped up to the flipchart to brainstorm a simple high power ignition alternative to a dedicated distributor, remote mounted coil and a necessary amplifier box, they set their sights on the high compression GM Performance Parts 572/720R crate motor. What better choice could you use as a target? The 572/720R comes out of the box with an excellent electronic distributor and capacitive discharge ignition system to make sure that everything that goes down the 1,090 cfm Demon carburetor throats is lit and converted to energy to drive the pistons harder and faster.
The goal was to outperform the GM-supplied components as well as offer additional features that the original system didn’t have. The original system works fine, but what if you don’t have room or just didn’t want to go through the hassle of mounting an external capacitive discharge box and running all the wiring? What if you wanted a custom ignition curve out of the box to allow stronger street and on-track performance? What if there was an ignition system that would plug right into that original HEI wiring already in your car or would only require a one-wire hookup?
After engineering the new self-contained H.E.I. distributor/coil package, they took it even further and developed the Mini-VIP to “step up” the 13 to 14 volts of charging system power to 18 volts for the ignition system alone. In addition to increasing wide open throttle performance, it’s a huge asset to help with the natural voltage drop that occurs when you are operating at low speeds with all the accessories running, like electric fuel pumps, electric fans, maybe an electric water pump, A/C or even a big stereo system. Low voltage decreases spark energy quickly.
To test the D.U.I. system, we needed a well sorted-out car that could put all of that GM Performance horsepower to good use and along came Randy Borelly with his ’79 Malibu. To Randy, there is nothing quite as cool as a sleeper that just doesn’t look the part. It’s that simple and unassuming image that draws you in and when the moment is just right, smacks you in the face with a full-on hammer blow that leaves you wondering what just happened.
Randy found his super clean 1979 Malibu with only 24,000 miles. It was all dressed in its pedestrian “school marm” green-on-green outfit that could easily fade into the scenery of any parking lot or commuter traffic jam. There was little trouble keeping excitement at bay (or even getting interested) with all 95 romping stomping horsepower screaming out of the 200ci V-6 under the hood. But this was perfect for what Randy had in mind. He engaged “cloaking mode” and got to work.
First, there was a motor-vation decision to make. Randy looked around and decided that the simplest way to handle things would be to select a crate motor from the GM Performance Parts catalog. Hmmn … 350ci/330hp? No way. 383ci/425hp? Yawn. 427 or 454 cid? Uh uh. 502/502? Well … maybe ... 572ci/620hp? Yeah, but what if …? 572ci/720hp? Wow! There it was, right at the bottom of the page! The biggest and baddest boy on the block, in stock and ready to rock. After Randy studied the details of the torture testing that the 572 engine development program subjected each and every component to, the deal was locked in.
The rest of the 3,400-pound sleeper came together as Randy worked around the basic parameters of retaining the bench seat, column shifter and hubcaps. Things like making the six-point rollbar blend in as much as possible. There are widened rear steel wheels that carry blackwall Hoosier drag radials along with some creative use of paint and hub caps on a set of aluminum Weld ProStar wheels on the front. And since part of being stealthy is making sure nothing shows, fuel tank sumps and exposed braided fuel lines under the rear of the car were definitely out of the question. The stock tank is still there, carrying pump gas for cruising, and the trunk acquired a small fuel cell for race gas at the track and electric fuel pumps that mimic the capabilities of the average offshore oil well.
The only non-stealth part was the necessary fiberglass cowl hood to clear all that engine, but with blended paint it doesn’t stand out too bad. To reduce weight, the inner fenderwells were removed, an aluminum radiator and OEM aluminum core support were installed, Strange front disc brakes were added, and countless other little tricks to shave a pound everywhere he could without hacking up the car. TE Snyder Fabrication helped Randy dial in the suspension to drive the rear tires into the pavement on every launch.
Dropping the tall deck 572 in place of the old V-6 wasn’t too difficult, since there were no air conditioning components, power steering or power brake booster in the way. A set of Lemon’s 2¼-inch headers fit well because unlike many aftermarket engines with this sort of power, the exhaust ports on the heads aren’t raised. The remainder of the exhaust consists of 3½-inch pipes with a Dr. Gas crossover and Dynomax Ultraflows. For a light but strong transmission, Randy used a Powerglide with a 1.87 first gear and bolted a nine-inch 4,500 rpm ATI stall converter in place. There was no way the rear axle was going to handle eight times the horsepower, so in went a Strange nine-inch rear with 3.90 gears screwed to a Detroit Locker.
With everything in place, nothing was left to do other than cruise the streets and drive it out to the track every chance there was. Heads would spin and the jaws hit the ground each time Randy dropped the hammer and lifted both front wheels high on the way to 9.80s/137 mph e.t.s. For the next three years, this was the Malibu’s regular routine.
To perform our test, Randy set the car up to quickly swap the distributors at the track. That meant coordinating primary wiring to both units as well as spark plug wires. A new set of plugs were gapped into place and it was off to the races with the D.U.I. unit up to bat first. Now understand, this 572 has been the regular play toy for the Borelly family for years and Randy is very accustomed to its manners. On the street, the timing is backed off to 30° total and it’s driven everywhere on 93 octane pump gas. When it’s time to play at the track, the timing is bumped to 36° and the Sunoco 110 octane race gas is brought into play with a simple opening of the gate valve in the Malibu’s trunk. Randy’s first impressions were “Wow … incredible throttle response!” Randy continued to say, “Having driven it for years, I know exactly how it acts and immediately I knew something was definitely different under the hood. It just feels so clean and crisp.”
The two-hour drive to the track on Sunday afternoon was uneventful and after going through tech inspection and bumping the timing, it was time to let ’er rip on the Piedmont Dragway 1/8th mile starting line. In only 49 minutes, Randy had made three passes and we had our baseline established with runs of 6.38 at 108.19 mph, 6.42 at 108.26 mph and 6.46 at 107.71 mph. The first run had the best launch with a 1.439-second 60-foot time. Subsequent attempts with a longer burnout didn’t seem to help as 60-foot times dropped off to a 1.479.
We were definitely “hot lapping” it with no cool-down periods after the first run to replicate real street use. The D.U.I. “plug and play” distributor never missed a beat though and pulled hard all the way through. After those runs and while Randy and his buddy Mike Miller were swapping the original distributor back in place, Randy noticed something he had never seen before. Approaching the car from the side, he noticed the side exit exhaust pipes had cleaned up from the normal black and sooty look to a very light gray color … which is something that had NEVER happened before. The D.U.I. folks had mentioned that it was common to need to “jet up” when switching to their H.E.I. and 18-volt stepper box … and from the color of the pipes and the plug readings, no doubt we could have definitely used more fuel. Considering the way the big 572 always ran, we didn’t figure it was blowing too much wasted fuel out the pipes, but it’s too bad we didn’t bring any bigger jets with us!
Next up was a switch back to the familiar GM/MSD distributor and capacitive discharge box. Doing our best to keep weather and starting line conditions from affecting our testing too much, Randy and his buddies had the 572 back at the Christmas tree within two hours for another hard “wheels in the air” pass. Managing to get in two passes within 21 minutes, Randy nailed a 6.30 at 110.42 mph and then a 6.32 at 109.89 mph. The 60-foot times for these runs were 1.417 and 1.438 respectively.
So what did we learn? First, Randy’s wife Susan is VERY understanding because right in the middle of our planned testing, an engine rebuild was required (see sidebar) as well as a move to another state for Randy’s new job! Try that at YOUR house! Next, obviously Randy has a killer street car, proven by how he spanked the Malibu hard by driving it to the track and pulled right to the line fresh off the street. How many nine-second cars can do that and look this tame? This testing was about as back to back as you can realistically expect to achieve. Same car, same driver, same track and same day.
While the D.U.I. system wasn’t faster this time, obviously there are some variables that you can’t easily overcome due to the time factor. The D.U.I. runs were made right off the street with precious little cool-down time as Randy made his way through tech and the staging lanes. After that, he was able to heat soak the engine some more (real life) and as you can see, the GM Performance 572/720 responded like any other motor, it got a little slower in e.t. and mph each time. Then we had a two-hour cool down for everything as the distributors were changed out and the timing reset before we got our next pass. This was definitely a factor in how the best run of the day was achieved because everything about that run was better; 60-foot, e.t. and mph through all incremental points. On the second run, the heat started to take its toll a little and e.t. and mph began to drop off again. The weather conditions stayed pretty constant throughout the afternoon though with only slightly better conditions later on that couldn’t have been worth more than a hundredth or so. Sure wish we had brought some jets and had time to tune it to the level that the original version had been brought to over the years.
Overall, it was a great test and proves that the old wives’ tales about an H.E.I. not being able to handle big horsepower and rpm are just that. Or maybe you just need a GOOD H.E.I.! The Davis Unified Ignition version, along with the Mini-VIP 18-volt stepper box, can obviously provide the energy required to light off some serious fuel in something as crazy as a GM 572/720R. It will allow you to install all of that power with only some simple wiring hookups. It couldn’t get much easier. Regardless of how much power you’re making, the right H.E.I can easily “Light Your Fire”!
Special Thanks To:
Street/strip D.U.I. distributor
Vacuum advance eliminator
FOR YOUR INFORMATION:
THE ENGINE SHOP
TE SNYDER FABRICATION
On the Growl
GM Performance really began the whole crate motor industry years ago. They combined proven components to produce engine combos to meet most any need from mild to wild. As usually happens in the hot rod world, things got a little out of hand, and eventually we were rewarded with the ultimate crate monster…the ZZ572/720R! The “R” stands for “RACE” which means GM had no intentions of this beast ever being considered a street engine. Of course they knew there were “Randys” out there that came from the same Sunoco 260 high octane fueled gene pool that spawned the original L-88 owners. And then later there were all the folks who bought them and the mega compression LS-7 454s over the counter to drop in their Saturday Night Specials. Concessions for street use must be made today just as they were then, but there are states where 100 octane is available at the pump right now!
The ZZ572/720R is rated at 720hp at 6,250 rpm and 685 lbs-ft at 4,500 rpm using S.A.E correction factors, which are a little stingier than the STD correction factor most race shops use. Starting with a 4.560-inch bored Gen VI tall-deck Bowtie block, GM had various high performance suppliers provide parts to test and survive the extended dyno torture sessions while making repeatable long lasting horsepower.
Durability was the key, not just banzai “one pass” power. A forged steel 4.375-inch stroke internally balanced crank was attached to forged 4340 H-beam rods and forged 12.0 compression full floating pistons. The heads have aluminum rectangular ports filled with 2.25/1.88-inch stainless valves actuated by full roller 1.7 ratio rocker arms that are pushed by a 266°/272° solid roller cam with .714/.714-inch lift on a 112 LSA. On top is a single plane intake and a Dominator style carburetor complete with a full multiple discharge spark ignition system. This thing comes complete with oil pan and windage tray, SFI approved balancer, water pump, spark plugs and wires as well as provisions for a mechanical fuel pump and two Z-bar linkage clutch linkage positions.
As we were about to start this test, the three years of highway driving and extended street use teamed up with the laws of physics to bite Randy hard. Just two blocks from home, a solid roller lifter decided to call it quits and took the cam with it. This meant a complete teardown to check for damage and remove any loose metal pieces. Lucky for Randy everything survived well and only a thorough cleaning, crank polishing and cylinder hone was required to go along with the new bearings and rings. The option to replace the cam with a nastier version was dropped since Randy was very happy with the street and race manners of the original one. As luck would have it, he was able to locate a new “take out” cam from another 572/720R and installed it with a new set of Isky Red Zone lifters and valvesprings. Special thanks goes out to The Engine Shop for getting the engine back together very quickly.
Any solid roller lifter is a “maintenance/wear item” and should be inspected regularly. This actually applies to all valvetrains, but frequently folks will second guess themselves and decide that “I must have missed the adjustment on that one” when they pull the valve cover a few thousand miles later to inspect some noise. That’s a fatal mistake. If it was loose when you last set them, it would have made noise immediately. If a valve adjustment is loose, or even .002 to .003-inch looser than the other valves, something has changed and you need to immediately stop running it until you positively find out what it is. If you clean roller lifters in lacquer thinner to remove all the oil from the rollers, you WILL feel the roughness and grittiness of the axle and needles starting to go away long before they completely stop rolling and eat the cam. Any sign of roughness is reason to replace/rebuild the lifters.