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#1
Posted 10-26-2021 07:28 AM
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At the track this weekend someone mentioned that I would need to remove the 6-speed transmission in my car and replace it with a 5-speed. Is this right????
Reading through the rules it doesn’t appear to say that but I’m only just starting so maybe there’s something I’m missing? Section 14.1 just says it has to be unmodified and stock for the year.
#2
Posted 10-26-2021 07:52 AM
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SCCA-GCR > Spec Miata 9.1.7.
2. Transmission/Final Drive
a. Transmission and final drive ratios must remain stock for the year of car. All cars shall only use the
5 speed transmission and the 4.3 differential ratio. Transmission gear ratios must be stock. All cars
may use the stock 4.3 unmodified OEM open differential or one of the approved alternates listed
below.
Chris
Happiness is a dry martini and a good woman ... or a bad woman.
- George Burns
#3
Posted 10-26-2021 08:08 AM
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SCCA
2. Transmission/Final Drive
a. Transmission and final drive ratios must remain stock for the year of car. All cars shall only use the
5 speed transmission and the 4.3 differential ratio. Transmission gear ratios must be stock. All cars
may use the stock 4.3 unmodified OEM open differential or one of the approved alternates listed
below.
NASA
14. Transmission / Clutch & Flywheel / Differential
14.1 Transmission
Transmission must be unmodified other than updating or backdating replacement parts. Gear
ratios must remain stock for the year of car. Shifters may also be updated or backdated but must
remain OE (90-05). Shifter bushing may be replaced with alternative materials not to differ in
function of OEM plastic shifter bushing.
Hmm!! 5 speed, 6 speed. See APPENDIX A which shows 5 ratios for all year cars.
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#4
Posted 10-26-2021 08:53 AM
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Any idea who in NASA I would contact to get clarification?
#5
Posted 10-26-2021 11:26 AM
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- Steve66 likes this
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#6
Posted 10-26-2021 11:47 PM
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And if your 2001 is an oem stock 6 speed it has a stock 3.9 rear end. Good news is that combination will fetch more than enough to replace with a 5 speed and 4.3!
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Ron
RAmotorsports
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#7
Posted 10-27-2021 09:21 AM
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So with the SCCA it’s clearly 5-speed only but NASA is unclear.
Any idea who in NASA I would contact to get clarification?
it's clear, its 5 spd and the 6 speed boxes are junk and not raceable IMO. Gates way too close
If goping to Sm, change, the sooner the better
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