Check out our stats from 10 pulls in one day.
The original “Drag Special” front tire from Moroso Performance (http://www NULL.moroso NULL.com/) has been a “must-have” item for decades, thanks to its light weight construction and lower rolling resistance. And that’s not all the parts maker is famous for. Since 1968, Moroso has pioneered the development of deep-sump oil pans, pan evacuation systems, vacuum pumps, and countless other performance systems and accessories.
Recently, the Drag Racer team was pleased to spend a day at Moroso Performance, where its team of engineers soundly thrashed a host of parts on the company’s DTS dyno. This aggressive project showed us (in real time) how a host of products have increased horsepower over the years.
Mule Engine Basics
The mule engine selected for this exercise was a 582-inch big-block Chevy provided decent results from most of the products tested here. However, it’s difficult to baseline such a wide variety of power producing items using one mule, as different combinations respond differently when applied to engines that put out either less or more grunt.
- 582-inch Big-Block Chevy
- 4.600-inch bore / 4.375-inch stroke
- 14:1 compression
- VP Racing Fuel (C-12 108-octane)
- DTS 4000 Dyno
- Water and Oil temperature (beginning of pull) 160 to 165 degrees
- Petroleum-Based 15W40 oil
- Dyno Pulls from 5,300 to 7,500 RPM
- Oil pan: #20401
- Oil pump: #22175
- Evacuation System: #68817 breathers w/ #68357 Valve Covers
- Peak H.P. 935
- Peak Torque 772
- Average H.P. 887
- Average TQ 732
- Average Oil Pressure 39.5
- Average Vacuum 0.00
- “Street Price” $819.86
RESULTS: This is the basic set-up that evolved from the early days of bracket racing engines. This initial test demonstrates what an engine with a street/strip pan and a standard volume oil pump will make for power. After 6,000 RPM the oil pressure dropped approximately 10 psi. Using six quarts with this set-up is suitable, but the stroke of the engine shows how it will affect the oil control in the oil pan. In most cases, this line of oil pans will produce restrictions on the performance of a 4.375-inch stroke (or higher) engine, as noted in our disclaimer at the end of the text.
CHANGE: #25900 Pan Evacuation Kit – Remove breathers, and install evacuation breathers and lines to pan evacuation bungs in collectors
Topic shown: The difference between the engine breathing versus a small amount of crankcase vacuum created. Many classes do not allow vacuum pumps, and many racers still use them.
- Peak H.P. 964 + 29
- Peak Torque 779 +7
- Average H.P. 904 +7
- Average TQ 745 +13
- Average Oil Pressure 38.1 psi (-1.4)
- Average Vacuum 5.04 in/hg +5.04
- “Street Price” increases $56.25
RESULTS: Releasing the crankcase pressure is essential to making power. Many classes of racing do not allow evacuation pumps or “vacuum pumps” by the rules, so making a “Pan-E-Vac” system work will gain power by creating some amount of vacuum. This type of system can be purchased for a minimal amount of money and effort to gain the numbers seen.
CHANGE: #22185 High-Volume Oil Pump and Pick-Up – drop oil pan, swap oil pump and pick-up, re-install #20401 pan.
TOPIC SHOWN: How the oil pressure and horsepower changes, based on increasing the oil pump size. Over the years, there has been endless discussions on how much power is used to turn a high-volume pump, and how much more oil pressure is created, along with volume.
- Peak H.P. 953 – 11
- Peak Torque 764 -15
- Average H.P. 890 -14
- Average TQ 733 -12
- Average Oil Pressure 45.0 psi +6.9
- Average Vacuum 5.14 in/hg +0.10
- “Street Price” increases $17.02
RESULTS: People always ask about needing a high-volume pump, which produces more oil pressure, thinking it’s going to be their savior. Well, it will give you more oil pressure, but a loss of nearly one-percent of the horsepower it takes to run your engine. This shows without a doubt that there is a cause and effect on making the decision to increase your oil pressure.
CHANGE: Remove #20401 oil pan – Install #21047 oil pan
TOPIC SHOWN: Changing over from a Street/Strip oil pan to a full Drag Race oil pan with kick-out and solid-louvered tray. This oil pan also has a 5-inch deep front sump versus the 4.5-inch deep stock sump. How this works above 6,500 RPM will show the advantages between a “Street/Strip Pan” and a “Drag Race Pan.”
- Peak H.P. 993 +40
- Peak Torque 780 +16
- Average H.P. 919 +29
- Average TQ 756 +23
- Average Oil Pressure 60.1 psi +15.1
- Average Vacuum 5.02 in/hg -0.12
- “Street Price” increases $203.50
RESULTS: This test clearly demonstrates how much better a Drag Race Pan performs over 6,500 RPM and makes a big difference in the horsepower. It will also make gains at lower RPM and increase the torque, thus improving the elapsed time of any car. This 582 cubic inch engine showed that the benefits are big. However, the gains will always be proportional to the size of the stroke in the engine. The oil pressure is more stable as the oil will return to the sump area far more efficiently, and gives a much smoother pressure trace.
CHANGE: Install 22640 Vacuum Pump System – (Remove pan evacuation system and valve covers) – Install #68356, and vacuum pump system (#22640, #63910, #22649, #22630, #64888 #97172, #63849, #85465)
TOPIC SHOWN: The gain from a three-vane vacuum pump. This is the company’s best selling vacuum pump, and is also its original design. Oil pressure changes, horsepower and torque gains, and installation were the highlights with this change. The pump was run at 50 percent of engine speed.
- Peak H.P. 1018 +25
- Peak Torque 791 +11
- Average H.P. 934 +15
- Average TQ 768 +12
- Average Oil Pressure 58.1 psi -2.0
- Average Vacuum 13.25 in/hg +8.23
- “Street Price” increases $1095.00
RESULTS: Creating more crankcase vacuum is worth power, even though we already had a Pan-E-Vac” System on it. The belt-driven vacuum pump created more vacuum, more consistently, throughout the power range (and at idle). In some cases the oil pressure will drop when this much vacuum is applied, but having an oil pump that is larger than what the system needs will often make up for the vacuum that will typically create more oil flow, and less oil pressure to read on the oil pressure gauge.
CHANGE: Install #22642 Vacuum Pump (remove #22640 pump and bracket)
TOPIC SHOWN: The difference between a three-vane and a four-vane pump on a wet-sump engine.
- Peak H.P. 1024 +6
- Peak Torque 797 +6
- Average H.P. 941 +7
- Average TQ 774 +6
- Average Oil Pressure 60.0 psi +1.9
- Average Vacuum 16.17 in/hg +2.92
- “Street Price” increases $140.29
RESULTS: The Moroso “Enhanced” vacuum pump works better in the area of vacuum than the “Original” design Moroso Vacuum Pump. This comparison shows the gain with a few inches of vacuum. On an engine this size, making and average of 16 inches of vacuum is about as much as you would want.
CHANGE: #21049 oil pan and #22187 oil pump combo (remove #21047)
TOPIC SHOWN: How well the new-style Steel Oil Pan and Shrouded Oil Pump work.
- Peak H.P. 1025 +1
- Peak Torque 802 +5
- Average H.P. 956 +15
- Average TQ 775 +1
- Average Oil Pressure 66.6 psi +6.6
- Average Vacuum 16.35 in/hg +0.17
- “Street Price” increases $31.89
RESULTS: While the peak numbers aren’t that different, the average horsepower number is much higher, and shows how oil pan tray design can increase power throughout the pull, and therefore, your run. Subtle changes can garner big results in oil pan design. Notice the better oil pressure throughout, as this pull was made with seven quarts of oil.
CHANGE: Install #22164 Billet Oil Pump (remove oil pan and swap oil pumps)
TOPIC SHOWN: The difference between a cast pump and a billet pump, in both horsepower and oil pressure.
- Peak H.P. 1025 0
- Peak Torque 803 +1
- Average H.P. 958 +2
- Average TQ 774 -1
- Average Oil Pressure 74.3 psi +7.7
- Average Vacuum 16.50 in/hg +0.15
- “Street Price” increases $290.28
RESULTS: The power didn’t change with the oil pump swap, even though it was a High Volume vs. Standard Volume change where we saw a gain in the previous pulls. But, you will notice how good the oil pressure was with a billet oil pump versus the cast iron pump housing. This will show that with all the power we are making, a standard-volume pump will keep up with (or exceed) what the end user would want for oil pressure.
Change: #20385 Aluminum Drag Race Oil Pan (remove #21047 steel oil pan), install race pattern gasket and stud kit #38361
TOPIC SHOWN: The difference in power and oil pressure with a larger sump and bigger kick-outs. Do these enhancements really make more power?
- Peak H.P. 1027 +2
- Peak Torque 805 +2
- Average H.P. 960 +2
- Average TQ 777 +3
- Average Oil Pressure 76.1 psi +1.8
- Average Vacuum 16.48 in/hg -0.02
- “Street Price” increases $168.60
RESULTS: The aluminum oil pan is lighter, easier to work with and has the full race bolt pattern and drain-back bungs. For this test, the 582’s stroke was not showing the gains that you would see on a 4.500-inch stroke (and up) combination. The aluminum pan holds the oil pressure and works very well over 8,000 RPM, a range which is commonly seen in today’s popular bracket racing engines.
CHANGE: #22843 Vacuum Pump (remove #22642 Vacuum Pump)
TOPIC SHOWN: Installing a large vacuum pump and making a bunch of vacuum. What does it do for power and oil pressure? How much is too much?
- Peak H.P. 1023 -4
- Peak Torque 799 -4
- Average H.P. 958 -2
- Average TQ 773 -4
- Average Oil Pressure 74.9 psi -1.2
- Average Vacuum 18.15 in/hg +1.67
- “Street Price” increases $213.73
RESULTS: Making “more” vacuum isn’t going to make you more power, as this pull shows. The #22843 Pro-Mod vacuum pump takes more power to drive, and will make more vacuum. But, as with anything, it will peak out. And on many engines this size, 16 inches of vacuum is typically the highest number you would want to see. Dry-sump engines will benefit from these vacuum numbers. Even with the high vacuum numbers, the standard-volume oil pump still maintained good oil pressure.
Moroso’s engineering guys went above and beyond the call of duty in order to complete 10 dyno pulls in one day. However, everything went off without a hitch and the end result came with a mountain of data that quantified each and every change that took place. We came away with new-found respect for the practice of research and development – something Moroso Performance used liberally while building its respected legacy. Of course, on-track testing (and winning) has always been another cornerstone of this company’s overall plan. Rest assured the same degree of engineering, research and development goes into the entire product line available from the Moroso Performance Products family, which includes Competition Engineering and Moroso Wire Technologies.
Moroso Performance Products (http://www NULL.moroso NULL.com/)
80 Carter Drive, Dept. DR
Guilford, CT 06437
www.moroso.com (http://www NULL.moroso NULL.com/)
Please note: Due to publishing schedules, the cost of parts as listed is subject to change, and can be considered a “ball park” number that will be close to what you’d expect to pay.