Building an engine for STR
#1
Building an engine for STR
Due to the oil pump grenading during the first track day of the year I am forced to rebuild the engine. The vehicle is a 95' with a JDM VVT engine which has the 10.5CR pistons. Current powertrain modifications include
-RB header
-Open air filter at end of NA crossover(It needs heat shielding)
-Magnaflow oem fitment cat
-Roadstersport cat back
-Running a diypnp MS1 with VVT controller
-COPS
Wanted to get into Solo this year and I just bought BFG Rivals so STR seems logical. I am curious what internal engine work will disqualify the car from STR.
Current plan of attack is a BE oil pump, 949 dampener, and balancing the rotating assembly so the oil pump grenading is not even a remote possibility anymore. Stock pistons/rods, a hand blended multi angle valve job. New bearings would be installed as well.
-RB header
-Open air filter at end of NA crossover(It needs heat shielding)
-Magnaflow oem fitment cat
-Roadstersport cat back
-Running a diypnp MS1 with VVT controller
-COPS
Wanted to get into Solo this year and I just bought BFG Rivals so STR seems logical. I am curious what internal engine work will disqualify the car from STR.
Current plan of attack is a BE oil pump, 949 dampener, and balancing the rotating assembly so the oil pump grenading is not even a remote possibility anymore. Stock pistons/rods, a hand blended multi angle valve job. New bearings would be installed as well.
#4
Back up a second. NA car + VVT motor is CSP or higher. Not STR legal. If the Chassis is a 95, then it needs to have a 95 motor. You can make a very VERY minor changes, but nothing really substantial. For instance the 94 pistons have been superceded for the 97 ones which is a 0.5:1 CR bump. No motor swaps, No port work, no BE gears(though I don't think anyone would care, but that's another discussion), no balancing. STR is STOCK internals. If you want to move to use the VVT motor in the 95 chassis then if you go back to the stock USDM 01-05 internals, you'll be CSP legal. There you'll have some more freedom, but not much. That's still stock internals, but porting is legal up to an inch, all exhaust and intake are free, etc.
Rules: The Sports Car Club of America - Solo
Rules: The Sports Car Club of America - Solo
#15
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The NA and Early NB Miatas can compete in STR, but it is course dependent. A highly transitional course with limited areas to use power gives the lighter Miata a slight advantage. But on a open course with flowing sweepers and "real" competition the early Miata will more times than not be left behind.
The truth is UNLESS you plan on running at the National level who really cares about having "the car." Just build the car how you want it...show up at local events and run it where it fits.
The truth is UNLESS you plan on running at the National level who really cares about having "the car." Just build the car how you want it...show up at local events and run it where it fits.
#18
Locally the NA is, but its down on power. The NB should still be competitive, even the car to beat, if someone would just build it. Its advantage has dropped a bit with the z2 and the rival coming out, but it should still have an advantage with the magical pixie dust tire in the wet and when the 225 rival comes out in the dry. A serious effort is going to take 2 very different setups and sets of tires for wet and dry. I shouldnt really say that the pixie dust tire might still be the tire to have in the dry.
#19
Locally the NA is, but its down on power. The NB should still be competitive, even the car to beat, if someone would just build it. Its advantage has dropped a bit with the z2 and the rival coming out, but it should still have an advantage with the magical pixie dust tire in the wet and when the 225 rival comes out in the dry. A serious effort is going to take 2 very different setups and sets of tires for wet and dry. I shouldnt really say that the pixie dust tire might still be the tire to have in the dry.
Maybe locally they are, but we have too many S2Ks with capable drivers here for an STR miata to be worth it.
#20
I donno, I've raced against some of those nc area str cars, if I wasnt a medeocre on a good day driver I would have been a lot closer than 2-3 seconds off the leaders. Especially since my car at the time pulled like a 1.6 and at both events the surface was against me, at devens it being like 60* out and I being the only car in STR on kooks, and at jersey just being unfamiliar with it and fighting a monster push.