Our SuperMiata street project car, my daily driver. The goal was to take our completely stock, high mileage and rough looking 95 R package into a clean daily driver that should pass emissions testing in every state. The car will be autocrossed and used for HPDE (Miata Challenge) now and then. I was after a very clean, OEM look. Current weight is about 2150lbs with a splash of fuel. 147whp on CA91.
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Suspension
We fitted Xida-S with 700/400 rates. RB 1.125" #54105 front sway bar. Rear is the OEM 12mm with urethane bushings for street, 14mm bar for track use. Prothane control arm and diff bushings, SuperMiata end links. Diff is the stock 4.1 type 1 Torsen.
Brakes are OEM Sport Brakes with our two piece rotors and XP10's up front, XP8's in back, stainless lines all around with Motul RBF600.
The car has an NB front subframe, spindles and depowered steering rack.
Engine
We blueprinted an NB2 motor with Supertech 11.0:1 83.5mm pistons that were shaved down to create 10.5:1 compression. Supertech valve springs, SCAT forged rods and ACL race bearings. The rest is 100% OEM parts. Head and bottom end is otherwise stock. We filled it with 5W30 Amsoil OEM street oil. Magnaflow Metal core cat. Exhaust is a custom built 2.5" stainless with a resonator and 16" Magnaflow muffler out back. ECU is a special Adaptronic 440 ECU configured just for this type of conversion. Thread on the ECU here http://forum.miata.net/vb/showthread.php?t=403239
Phase one - Emissions compliance
As an experiment, we initially built the car with an EUDM header and heatshield to retain a full OEM appearance and functionality. We also kept the OEM NA8 airbox and NB2 MAF. With all that OEM hardware and a cat, we squeaked out 126whp on CA91. Guessing another 2-3whp with 93 octane fuel as we were det limited when tuning for 126whp.
Phase two - make a little power
Next we experimented with a few different intakes and settled on a K&N 600-6900 CARB legal kit. With that kit installed we made 147whp after wrapping the crossover pipe in thermal sheet and adding a Racing beat header. With the header, our CARB emissions compliance went out the window.
For now the car has no oil cooler but we'll add a very small Setrab with -10 push on hoses and Mocal thermostatic sandwich plate. Koyo 37mm radiator and Koyo cap with M-Tuned reroute.
Drivetrain
6 speed trans running Amsoil MTG. Clutch is a clutchnet stage 2 for 1.6 (200mm), organic sprung hub. Lightweight 8.8 lb Cr-Mo flywheel. 15x9 6UL's on 225/454 RS3's running about 26psi. I painted the wheels Ford tungsten gray code T8.
Miscellaneous bits
Harnesses are G-Force 5 pt camlocks. Seats are OMP Grip with custom made fixed brackets. Bar is a Hard Dog HC DD. Wheel is a Momo 350mm mod 78, NRG 2.5 QR and Momo hub.
We added V8 Roadsters subframe braces for added torsional rigidity. We'll some E-Code 55/65 halogen lights so we can actually see where we are going once the sun goes down.
John did a partial wire tuck under the hood. The relay box and ECU are behind the pax airbag cover.
Driving it
It's a blast! Amazing throttle response and torque way down low. The gearing and light flywheel let it zip through the gears like a kart. The ride with the 700/400 Xida-S is very firm but not harsh at all. Feels a bit lumpy at very low speeds but smooths out and begins to glide once you start hammering it. Brakes feel amazing. Super sensitive, tons of power. The XP's dust quite a bit but that's typical.
At the first SV autocross, we took TTOD on the RS3's. At Miata Challenge round 1 at Buttonwillow 13CW last Sunday, it was the fastest Miata overall. Clocking a 2:02.813. That's almost 2s under the Spec Miata lap record, and we did it on "street" tires. Very happy with how the car turned out and it's faster than I thought it would be.
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Suspension
We fitted Xida-S with 700/400 rates. RB 1.125" #54105 front sway bar. Rear is the OEM 12mm with urethane bushings for street, 14mm bar for track use. Prothane control arm and diff bushings, SuperMiata end links. Diff is the stock 4.1 type 1 Torsen.
Brakes are OEM Sport Brakes with our two piece rotors and XP10's up front, XP8's in back, stainless lines all around with Motul RBF600.
The car has an NB front subframe, spindles and depowered steering rack.
Engine
We blueprinted an NB2 motor with Supertech 11.0:1 83.5mm pistons that were shaved down to create 10.5:1 compression. Supertech valve springs, SCAT forged rods and ACL race bearings. The rest is 100% OEM parts. Head and bottom end is otherwise stock. We filled it with 5W30 Amsoil OEM street oil. Magnaflow Metal core cat. Exhaust is a custom built 2.5" stainless with a resonator and 16" Magnaflow muffler out back. ECU is a special Adaptronic 440 ECU configured just for this type of conversion. Thread on the ECU here http://forum.miata.net/vb/showthread.php?t=403239
Phase one - Emissions compliance
As an experiment, we initially built the car with an EUDM header and heatshield to retain a full OEM appearance and functionality. We also kept the OEM NA8 airbox and NB2 MAF. With all that OEM hardware and a cat, we squeaked out 126whp on CA91. Guessing another 2-3whp with 93 octane fuel as we were det limited when tuning for 126whp.
Phase two - make a little power
Next we experimented with a few different intakes and settled on a K&N 600-6900 CARB legal kit. With that kit installed we made 147whp after wrapping the crossover pipe in thermal sheet and adding a Racing beat header. With the header, our CARB emissions compliance went out the window.
For now the car has no oil cooler but we'll add a very small Setrab with -10 push on hoses and Mocal thermostatic sandwich plate. Koyo 37mm radiator and Koyo cap with M-Tuned reroute.
Drivetrain
6 speed trans running Amsoil MTG. Clutch is a clutchnet stage 2 for 1.6 (200mm), organic sprung hub. Lightweight 8.8 lb Cr-Mo flywheel. 15x9 6UL's on 225/454 RS3's running about 26psi. I painted the wheels Ford tungsten gray code T8.
Miscellaneous bits
Harnesses are G-Force 5 pt camlocks. Seats are OMP Grip with custom made fixed brackets. Bar is a Hard Dog HC DD. Wheel is a Momo 350mm mod 78, NRG 2.5 QR and Momo hub.
We added V8 Roadsters subframe braces for added torsional rigidity. We'll some E-Code 55/65 halogen lights so we can actually see where we are going once the sun goes down.
John did a partial wire tuck under the hood. The relay box and ECU are behind the pax airbag cover.
Driving it
It's a blast! Amazing throttle response and torque way down low. The gearing and light flywheel let it zip through the gears like a kart. The ride with the 700/400 Xida-S is very firm but not harsh at all. Feels a bit lumpy at very low speeds but smooths out and begins to glide once you start hammering it. Brakes feel amazing. Super sensitive, tons of power. The XP's dust quite a bit but that's typical.
At the first SV autocross, we took TTOD on the RS3's. At Miata Challenge round 1 at Buttonwillow 13CW last Sunday, it was the fastest Miata overall. Clocking a 2:02.813. That's almost 2s under the Spec Miata lap record, and we did it on "street" tires. Very happy with how the car turned out and it's faster than I thought it would be.
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