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notorquemiata-2

Slow Boring No Torque Miata (Spring <del>22</del>23)

Plan

Block

  • Mazda BP6D Block with 10.0:1 Pistons
  • Oliver Conrods
  • ARP Main Studs
  • ARP Head Studs
  • Boundary Stage 2 Oil Pump
  • Oil Pan Baffles
  • Hastings Rings | 30 Euro
  • ACL Main Bearings | 100 Euro
  • ACL Rod Bearings | 60 Euro
  • Head Gasket | 30 Euro
  • Honbürste | 80 Euro
  • Mazda BP6D VVT Head
  • Porting
  • Adjustable Chinese Exhaust Cam Gear
  • CatCams Valve Springs | 170 Euro
  • Valve Stem Seals MAZDA!! | 200 Euro

Long Story

In the current state, the car has around 230250whp and is, at least to this point, reliable even under heavy use. Octane requirement is 95102 RON / 9195 AKI, this seems reasonable for 9.5:1 and 0.60.82 bar (912 psi). The intake air temperature is only 10 K above ambient temperature which leads to the conclusion that the current setup is somewhat efficient.

The goal for the next stage should be a significant gain in power while maintaining reliability and practicability.

Related:

Power Goal

As one can see, the airflow of the supercharger at reasonable efficiency (~0.65) is around 0.36kg/s.

In theory, this should lead to at least 360whp. Previous archivements were 302whp @ 6.74krpm by bigb5031, 93krpm @ supercharger. Supportive mods were I/H/E and mild head work, stock 9.5:1 compression, 98 RON / 93 AKI.

315whp @ 7.317krpm by trackdogracing, 100krpm @ supercharger, I/H/E, E85.

324whp @ ~7.3krpm by kraftwerks, 100krpm @ supercharger, mods unknown.

Constraints and Limitations

  • Torque output should be under 250lb/ft / 340nm (at the wheels)
  • Octane requirement must be ordinary 98 RON or lower. 100 / 102 / E85 is not an option. fuck it
  • Engine should not be knock limited, even under harsh conditions (45 C ambient / track use)

Decisions

  • Target RPM
    • 105mm sc: 8500
    • 100mm sc: 8100 - 161 mph / 259 kmh ←- current state
    • 95mm sc: 7700 (101 Euro + S&H) - 153 mph / 246 kmh
    • 90mm sc: 7300 (81 Euro + S&H)

95mm would be “optimal” but would limit rpm to 7700.

Smaller pulley would lead to more belt slip probability.

Engine Block (draft)

  • Pistons: Wiseco K590M84 84mm 10.0:1 OR Mazda NB2 83mm 10.0:1 used with new hastings (2C4651) rings - cost: 30 Euro
  • Conrods: Oliver A-Beam

  • Head Studs: ARP
  • Main Studs: ARP
  • Rod Bearings: ACL Race
  • Main Bearings: ACL Race
  • Thrust Bearing: Mazda
  • Oil Pump: Boundary Stage 2

Head (draft)

  • VVT
  • Manley Intake Valves (Back-Cut)
  • CatCams followers
  • CatCams Springs
  • 6mm Lash Caps
  • Tomei Cams, why?

notorquemiata-2.txt · Last modified: 2023/09/01 03:51 by imakeyoufast