OneDirt

Building a good circle track engine involves much more than bolting together a good set of rotating components, slapping a great set of heads and a carb onto it, and heading out to the track. Engine driven accessories like the water pump, power steering pump, and alternator can be the difference between winning or fighting an uncontrollable car with electrical failure that overheats and blows up. Serious thought and planning needs to go into building an effective front pulley drive system. Thinking about machining every spacer and bracket and playing with mounting brackets for hours on end to get the pulley alignment correct makes us break out into a cold sweat. So, we went to the experts in front drive systems, KRC Power Steering, to help us dial in our accessory drives.

The Company

KRC has been producing front drive kits and parts for years, and they are famous for taking the headache away from car builders that are trying to figure out how to power their engine driven accessories. KRC built a solid reputation with their power steering pump systems and have branched out from there. Located in the heart of stock car racing, Kennesaw, Georgia, these folks have seen just about every type of car conjured up for dirt track racing. The Chevrolet engine kits are by far the most popular, and that’s the KRC kit that we bought for our street stock project car.

The Options

On the very popular small block Chevy engine there are a number of different configurations for the accessory drive pulleys. There is the cylinder head mounted power steering pump or the block mounted. Also, there is the head mounted alternator, block mounted alternator, or none at all. These are just a few of the options that a race car builder has to consider when putting the car together. While it may seem innocent enough, there are some big time repercussions if the builder makes poor choices. Power steering failure, electrical failure, and cooling problems can all lead to a destroyed engine and can be traced to poor engine accessory drive engineering.

Our Choice for the SBC Street Stock Engine

The small block Chevy 350 engine in our project car is a vintage early ‘70s four bolt main truck engine. And as such, it came stock with vee belts and vee belt pulleys. Vee belts were the standard drive belt since they were invented in 1917 by John Gates of the Gates Rubber Company. The biggest drawback to the vee belt was that the pulleys on the accessories driven by the vee belt needed to be large enough to have a deep V groove in order to “sit” without twisting. Ford Motor Company began using a serpentine belt, developed by Jim Vance (also of the Gates Rubber Company), for use on the 1979 Mustangs. The serpentine belts have proven to be more efficient than the traditional vee belts because a single serpentine belt can drive all the accessories that had previously required multiple vee belts. Using a single wider belt also meant that the belt could be put under higher tension without stretching. Higher tension on the belts reduces both belt slip and load on the engine by allowing the use of lower ratio pulleys. Knowing the advantages of the serpentine belt drives, this was an easy choice for us. Our previous issues with throwing vee belts under racing conditions had been well documented, and we were not about to go through the same heartbreak again.

The next question we needed to tackle was the issue of what accessories our system would need to drive. The water pump was a certainty. After judging the fitness of our driver, we knew that we needed a power steering pump. Only the alternator remained as the only questionable accessory. We decided we would either be running an alternator or the driver would buy a generator, a battery charger, and be responsible for charging the battery before and in-between races. After some careful deliberation by the driver/car owner and the onedirt team, we bought the KRC 16316110 Chevrolet Crate Engine Kit with alternator brackets and a Powermaster 12 volt, 100 amp, single wire alternator.

The KRC Chevrolet Crate Engine Kit

We talked with Mike Deppa of KRC about their Chevrolet Crate Engine Kit, and Mike told us, “We have offered this kit since the early 2000’s. We sell 400 to 500 units of these every year, so they are a popular kit.” The KRC kit (KRC #16316110) comes complete with a short aluminum water pump, block mount power steering pump, alternator bracket and pulley, two serpentine belts, and all the gaskets, spacers, and hardware needed to assemble the front drive kit. According to Deppa, “We recommend getting the kit with the water pump because it makes it easier to get the proper alignment of the pulleys.” Deppa also explained that they also have a pulley kit with a tensioner. “A lot of race teams don’t understand how important the tensioner is in a serpentine belt system, especially on the dirt tracks. The water pump pulley has a tendency to experience belt slip because of the throttle action and extreme range of rpm. A tensioner will help control any belt slip on the pulley.”

Our kit came with a 3 1/2 inch alternator drive pulley, which is recommended by KRC to get the alternator to start charging at 2400 rpm pulley speed and approximately 2700 rpm engine speed. We purchased a Power Master 100 amp heavy duty one-wire alternator, so we opted to go with a smaller 2 1/2 inch diameter pulley which lowered the charging rpm to about 1900 engine rpm. This would eliminate some of the previous charging issues that we had experienced.

KRC’s Power Steering Pump

The Crate Engine Kit comes with a KRC power steering pump with bolt on reservoir. According to Deppa, “There is no difference between the remote reservoir system and the bolt on reservoir system except space considerations. The bolt on tank system removes the extra hose and the -10 fittings from the tank to the pump. Most of the problems that we see with power steering pumps are generated by improper installation of the hose or using the wrong fittings. The bolt on tank eliminates those problems and reduces weight.”

KRC’s Power Steering Pumps Tips and Tricks:

• Never start your engine without fluid in the reservoir tank. One minute without fluid can permanently damage the pump.
• Route all hoses and reservoir tanks away from headers to keep from adding heat to the system and burning the fluid.
• Use clear high temperature power steering fluid and change it on regular basis. KRC highly recommends using KRC Power Steering Fluid.
• Fluid level in the tank must be two or more inches higher than the top of the pump.
• When assembling new hoses, clean them with a rifle bore brush, then flush them out with hot water and air dry before use. Most problems with power steering systems are due to contamination from new hoses or other steering components, which in turn damages the pump. Always place caps on pumps, steering gears, and hoses when system is open to the air.
• Do not install any filters or coolers on the -10 side of the reservoir. Install them on the return side if they are needed.

KRC’s Power Steering Hose Tips and Tricks:

• Power steering pumps require a hose with a vacuum rating of 28 inches/HG on the inlet side and a minimum 1/2”inside diameter. This is required to keep the hose from collapsing at higher RPMs. A collapsed hose will damage the pump because there is no way for the pump to intake enough fluid to meet its requirement through such a small hole.
• Push-lock hose may be the proper inside diameter, but the vacuum rating is only 18 inches/MG. As the fluid warms up, this rating actually goes down. Push-lock hose will suck shut anywhere there is a bend in it, starving the pump of fluid and potentially causing severe damage to the internals of the pump.
• The -6 pressure hose, leaving the pump, must have an operating pressure of 2,250 psi. and an inside diameter of .31”. Common hydraulic hose may have the proper operating range, but their inside diameter is slightly smaller. The smaller diameter can restrict the flow to the steering gear. This can cause problems in your steering, such as tight spots in the turns and increased driver effort.
• Make sure the -10 feed line from the reservoir tank, remote tanks only, has a 1/2” inside diameter. Some companies have been importing tanks to the U.S. that have a 3/8” inside diameter. This will restrict flow to the pump and will damage the pump within a few races.
• KRC only recommends Aeroquip AQP high pressure power steering hose and fittings.

Installing the KRC Front Drive Kit

Getting ready to install the front drive kit is simply a matter of removing all the accessories from the front of the engine, draining and removing the radiator, and removing the water pump and crankshaft pulley. With all these components out of the way, it really opens up the engine compartment which makes it the perfect time to take a good look around and see if there are any other problem areas that were previously hidden. We didn’t find any issues that needed immediate correction, so we pressed on with our installation.

It’s an unwritten rule that “real men” don’t read instructions, but in this case we highly recommend going by the KRC printed instructions word for word. The KRC engineers have designed the front drive kit with spacers that are specific to the engine block and manufacturer’s allowable casting variances. In order to get the pulley alignment correct and ensure that the serpentine belt and aluminum pulleys in the kit have a decent life span, the instructions need to be followed in their entirety. KRC’s Mike Deppa told us of a driver that refused to read and follow the installation instructions and had to replace the water pump pulley every fourth race until he finally installed the system according to the instructions. Our crew wasn’t going to take any chances, so we dug the instructions out of the garbage can and started with step one.

R-LOK Crank Adapter Hub

Our installation started off by installing KRC’s proprietary R-Lok crank adapter hub. Deppa explained that the R-Lok system is a “three cam lock assembly that is milled on a center point. The R-Lok system was designed to be a dynamically balanced hub that reduces pulley wobble.” Even with three pieces to the assembly, the R-Lok system is still quite easy to install. Using three 3/8ths” X 1 1/4″ bolts, which are included in the kit, the hub adapter is tightened to the harmonic balancer. Once the hub adapter is torqued to the proper specs, a 3/8ths inch spacer is installed into the hub adapter to move the crank pulley away from the front of the engine and line it up with the new water pump pulley. The third piece in the R-Lok assembly is the crank pulley itself. Using the supplied 7/16ths 4 inch long crank bolt, a flat washer, and a lock washer, the pulley is inserted into the R-Lok spacer and secured to the crank snout.

KRC’s Aluminum Water Pump (#15101001)

The water pump included in the Crate Engine Kit is the base from which all the other brackets, spacers, and pulleys are engineered to and ensures proper pulley alignment between all the engine driven accessories. The water pump installs virtually the same as any small block Chevy water pump with the exception of adding the alternator bracket and spacers on the passenger’s side of the water pump. Because factory manufacturing allowable variances exist, you may need to add a thin washer to the alternator bracket to get it perfectly aligned with the crank pulley and water pump pulley. The mounting bosses on alternators have some variance in machining between manufacturers, so if you are attempting to use anything other than the PowerMaster alternators, there maybe some additional spacing required.

KRC’s Power Steering Pump (#31415000)

We chose the block mounted power steering pump for several reasons including availability, space requirements, and keeping the weight center as low as possible on the car. Attaching the power steering pump to the block is as simple as bolting the mounting plate onto the block with a couple of spacers to properly locate the pump pulley for alignment and then attaching the power steering pump to the mounting plate. Once the power steering pump is mounted in place, the water pump pulley can be installed with the four 5/16ths” flush mount screws that are included in the hardware package.

Alternator Installation

If you don’t learn a lesson with each project then you are not trying new things. We tried something new and ended up learning one of those school of hard knocks lessons. Our original intent was to use a stock alternator on the KRC bracket, however, when we attempted to install the alternator we found that the mounting bosses did not line up correctly and the pulleys were misaligned horribly. With our lesson learned and no speed shop in the local area, we placed an overnight order from SouthWest Speed for a Powermaster single wire racing alternator.

When our alternator arrived in the overnight mail, we headed back to the shop to complete the installation. We chose to step down our pulley size on the alternator to a 2 1/2″ pulley, so our first step was to remove the 3 1/2″ pulley that came on the alternator. Using the new hardware provided with the KRC kit, we installed the smaller pulley on the alternator and placed it in position on the mounting brackets. Two bolts is all that holds the alternator to the mounting bracket, so within a matter of minutes we were ready to install the 37″ serpentine belt and check our alignment. Then we installed the 3 rib belt that drives the alternator and checked all of our fluid levels.

Finishing the Installation

Once the serpentine belt was installed, the tension checked, all the power steering hoses connected, and all the electrical wires for the alternator connected, we started the engine and let it run for 10 minutes. After a brief moment to let the car cool slightly, we did a final check on the belt tension for both belts and started getting our car ready for the track. This time we were positive that there would be no more flinging belts during the heat races and no more battery charging problems. We were confident that these previous issues would now be solved by our KRC kit. Going to the track for the next race was going to be less of an adventure and more of a race.