I-Rotary Renesis Apex Seal Dynamometer Test

These tests were performed by Mr. Daryl Drummond of Drummond Enterprises in late 2021.  The tests compared the performance of a Normally Aspirated Pro Formula Mazda Renesis Engine with a set of the I-Rotary Renesis Apex Seals versus that of a similar engine assembled with the Mazda Renesis apex seal.

Daryl Drummond has developed and built 1000’s of high-performance rotary engines since the early 1980s.  In our opinion, he is an eminent authority on extracting the maximum performance and reliability of the Mazda Renesis rotary engine since its introduction to the North American market in 2004.

We were very fortunate to have had his talents validate the performance and quality of the I-Rotary Renesis Apex Seal.

The Test

Mr. Drummond compared the engine dynamometer performance of one of his best Renesis Pro Formula Mazda engines, assembled with the Mazda Renesis apex seal, to the dynamometer performance of a similar Renesis engine assembled with the I-Rotary Renesis Apex Seal using a Superflow engine dynamometer (dyno).

His initial results with the engine assembled with the I-Rotary Renesis Apex Seals were so impressive after 25 dyno pulls that he thought there was some malfunction with the calibration of his dynamometer.  The following day, he recalibrated his dynamometer cell and performed an additional 25+ pulls on this engine with equally impressive results.

The detailed dyno charts from these tests are found at the end of this page.

Power Gains

The engine assembled with the I-Rotary Renesis Apex Seal yielded an unbelievable increase of 11+ peak HP (8.5+ kW) and 5.3 lb-ft (7.2 N-m) at peak torque when compared to one of his best engines assembled with the Mazda Renesis apex seals for this class (see dyno graph and charts below).

Anyone who has worked with the Mazda Renesis rotary engine knows how difficult it is to improve the performance of this engine by only 2-3 HP (1.5-2.2kW) in a normally aspirated configuration.

Additionally, the drop in power difference between the peak horsepower to the horsepower obtained at the highest engine dynamometer tested speed of 8,500 RPM was only 3.4 horsepower (2.5 kW) in the engine using the I-Rotary Apex Seals versus 9.5 horsepower (7.4 kW) in the engine using the Mazda Renesis apex seals.

The much lower drop in performance between the peak power at 8,100 RPM and the power at 8,500 RPM from the engine using the I-Rotary Renesis Apex Seal is a strong indication that this engine could have achieved an additional power increase by modifying the engine management program (MAP) so that it could match the better sealing performance of our seals.

According to Mr. Drummond, the engine management system for the Pro Formula-Mazda Renesis Engine race car has been designed with only four (4) tuning settings or adjustment options to limit the development of expensive or costly MAPs.  The fuel and timing settings on this MAP were designed to safeguard the reliability of the factory apex seal.  When he was doing the tests with the engine using the Renesis I-Rotary Apex Seals, he was at the leanest possible option available with this engine management program.  With more flexibility in the tuning settings, one may be able to obtain additional performance out of the engine using the I-Rotary Apex Seal.

I-Rotary vs. Mazda Hp and Torque Comparison Graph

Lower Exhaust Temperatures

In our opinion, the most impressive finding from these tests is that the additional performance increase was achieved with a 165°F (74°C) drop in exhaust temperature at peak power and an incredible 177°F (98°C) drop in exhaust temperature at the maximum RPM of 8,500 RPM.

This drop in exhaust temperature is a clear indication that the I-Rotary Apex Seal helps the engine maximize its combustion efficiency through better sealing when compared to the performance with any other apex seal.  The better sealing quality of any of the I-Rotary Apex Seals is due it is higher “Hot Compression” engine sealing capability.  This higher “Hot Compression” engine sealing capability allows the energy of the fuel to generate power rather than to be wasted as unburned fuel through the exhaust, which always results in high exhaust temperatures.

I-Rotary Exhaust Temp Graph

Long Lasting Performance

Another important result from this test is that the performance of the engine with the I-Rotary Renesis Apex Seals remained the same after the 50+ pulls on the dynamometer as it was after the initial 25 dyno pulls.  In other words, the power never dropped.

According to Daryl Drummond, this is also a very impressive result since it has been his experience that the Renesis engines prepared with the Mazda Renesis apex seal tend to drop in power after 25 pulls on the engine dynamometer, so his dynamometer testing of the Renesis engine with factory apex seals is restricted to well below the maximum of 25 pulls or 25 accelerations.

Rotor Housing Condition

He also mentioned that after engine disassembly, the rotor housings chrome surfaces were in very good condition and similar to the condition observed on the rotor housings of engines using the factory Renesis apex seal.

Advantages of the I-Rotary Renesis Apex Seal

The advantages of the I-Rotary Renesis Apex Seal over the best alternative Mazda apex seal are:

    • I-Rotary Renesis Apex Seal showed a total gain of 11+ HP (8.5+ kW) at peak power and 5.3 lb-ft (7.2 N-m) at peak torque.
    • The I-Rotary Renesis Apex Seal has longer lasting performance.  The Mazda or OEM Renesis apex seal often lasts 25 engine dyno runs before the peak HP and Torque begin to decrease. The I-Rotary Renesis Apex Seal never lost any performance, even after 50+ engine dyno runs.
    • The I-Rotary Renesis Apex Seal lowered the exhaust temperature by 165°F (74°C) at peak power and 177°F (98°C) maximum RPM. This dramatic reduction in temperature is due to the better “Hot Compression” sealing characteristics of the I-Rotary Apex Seal.
    • The chrome surface of the Rotor Housings with the I-Rotary Apex Seal was as good as the surface of the rotor housing using the OEM or factory apex seal.

    Learn about the I-Rotary Renesis Apex Seal RX-8 Performance / Track Test here


    Dyno Test Data Using I-Rotary Renesis Apex Seals

    This engine dynamometer engine test was performed at Drummond Enterprises on September 21, 2021 in a Pro Formula Mazda Renesis Engine.

    The engine gained 11+ extra HP (8.2+ kW) and exhibited an exhaust temperature reduction of 165 degree F (74 degree C) at peak power with the I-Rotary Renesis Apex Seals.

    These power numbers were obtained after 50+ Pulls on the Engine Dynamometer.

    The 50+ pulls on the engine dynamometer were done in 2 sessions:

      1.  The first 25 pulls on the engine dynamometer were done in the 1st session in one  day.

      2.  In the 2nd session, an additional 25+ pulls were performed the following day, after the engine dynamometer was recalibrated.

        Daryl Drummond was trying to validate the gained power results obtained after the Initial 25 Pulls as well as to find the point of the loss of power on the engine Dyno with the I-Rotary Apex Seals, which never happened.

         

         I‑Rotary Renesis Apex Seal Engine Dynamometer Results

        Engine Speed
        RPM
        SIPI-Tr
        Cal. lb-ft
        SIPI-Pw
        Cal. HP
        Exhaust 1
        Deg F
        Exhaust 2
        Deg F
        6000
        185.6
        212.0
        1302
        1283
        6100
        185.1
        215.0
        1305
        1288
        6200
        185.4
        218.8
        1308
        1292
        6300
        185.7
        222.7
        1312
        1298
        6400
        188.0
        229.1
        1316
        1304
        6500
        192.0
        237.6
        1324
        1315
        6600
        193.7
        243.5
        1328
        1321
        6700
        195.4
        249.3
        1334
        1329
        6800
        196.4
        254.3
        1340
        1335
        6900
        196.3
        257.9
        1343
        1339
        7000
        195.7
        260.9
        1350
        1347
        7100
        195.1
        263.8
        1358
        1356
        7200
        194.0
        265.9
        1365
        1362
        7300
        192.2
        267.1
        1372
        1370
        7400
        191.0
        269.1
        1378
        1375
        7500
        188.8
        269.6
        1384
        1381
        7600
        187.4
        271.2
        1393
        1388
        7700
        186.5
        273.5
        1399
        1393
        7800
        184.7
        274.2
        1407
        1400
        7900
        183.3
        275.7
        1411
        1404
        8000
        181.2
        276.0
        1420
        1412
        8100
        180.0
        277.6
        1425
        1416
        8200
        177.3
        276.8
        1429
        1420
        8300
        174.9
        276.4
        1432
        1422
        8400
        172.2
        275.4
        1435
        1425
        8500
        169.4
        274.2
        1438
        1428

         

        Dyno Test Data Using Mazda Renesis Apex Seals

        This engine dynamometer engine test was performed at Drummond Enterprises on December 16, 2021 in a Pro Formula Mazda Renesis Engine.

        According to Daryl Drummond, this power curve data below is typical of one of the best engines he has built for this class

        Important to also mention is that these power numbers were obtained after a few pulls on the Engine Dynamometer.  Mr. Drummond does not like to do more than 25 pulls on the engine dynamometer when using the factory apex seal because it has been found that often these engines begin to drop in performance.

         

         Mazda Renesis Apex Seal Engine Dynamometer Results:

        Engine Speed
        RPM
        SIPI-Tr
        Cal. lb-ft
        SIPI-Pw
        Cal. HP
        Exhaust 1
        Deg F
        Exhaust 2
        Deg F
        6000
        182.3
        208.3
        1416
        1394
        6100
        182.6
        212.1
        1423
        1402
        6200
        182.4
        215.3
        1431
        1410
        6300
        181.8
        218.1
        1439
        1419
        6400
        182.8
        222.8
        1447
        1428
        6500
        186.2
        230.5
        1456
        1440
        6600
        189.7
        238.3
        1468
        1453
        6700
        190.8
        243.4
        1476
        1462
        6800
        191.1
        247.5
        1486
        1473
        6900
        190.1
        249.8
        1494
        1481
        7000
        189.0
        251.8
        1507
        1497
        7100
        188.6
        254.9
        1516
        1507
        7200
        186.5
        255.7
        1524
        1516
        7300
        185.1
        257.3
        1532
        1523
        7400
        182.5
        257.1
        1538
        1530
        7500
        180.3
        257.4
        1539
        1538
        7600
        180.1
        260.5
        1541
        1542
        7700
        179.2
        262.8
        1549
        1548
        7800
        178.8
        265.5
        1565
        1559
        7900
        177.1
        266.4
        1575
        1569
        8000
        174.5
        265.9
        1585
        1579
        8100
        172.5
        266.0
        1591
        1586
        8200
        169.9
        265.3
        1596
        1591
        8300
        166.1
        262.5
        1602
        1597
        8400
        161.6
        258.5
        1609
        1604
        8500
        158.7
        256.9
        1615
        1610

         

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