I have been thinking it might be time for us to start campaigning to our local directors and Greg himself to lower the A-arm penalty for 2021. -.7 is WAY too much, that is greater than going from RWD to FWD or AWD.

Part of the reason strut cars are less competitive is fewer people want to race them so they are going to be less developed on average.

I started a thread on nasa forums. Post there and contact your Greg directly:
https://community.drivenasa.com/topi...a-arm-penalty/
https://timetrial.nasaseries.com/contact-us/

Bump.

-2021 basically wrapped up in every region. 2022 rules do out by end of month suposedly.
-Lightweight/low power really fun to drive but really hard to race, duh.
-ST5 cars "can" cross over to GLTC kinda OK

content to spark some 2022 xT5 discussion:

2022 Rules are live.

https://nasa-assets.s3.amazonaws.com...1--12-1-21.pdf

Key changes are:
Allowed ballast up to 300lbs
-Cable actuated throttles get a .2 credit
-New tire modifiers
-A new credit for running tires smaller than you're allowed

My theoretical "budget z3 swapped", cable throttled, 300lbs of ballast, 2400lb NB1 on 205/8.5" R7s looks pretty solid at first glance with no calculator work.

Where did they hide the 2022 ST 1-4 rules ?? Specifically TT 3 ?

Never mind answered my own question.

https://nasa-assets.s3.amazonaws.com...1--12-1-21.pdf

https://nasa-assets.s3.amazonaws.com...1--12-1-21.pdf

https://nasa-assets.s3.amazonaws.com...m--10-1-20.pdf

Yeah, looking like I can drop ~40lbs or gain ~5avg hp if I run the 205 R7s on 8.5s. I think I'm leaning towards doing another tune to gain ~5hp as that setup will be 2550+lbs so -0.2 weight mod factor instead of -0.3.

Either way, my car in 5 will be faster in 2022 than in 2021.

Ok, I started running the numbers in more detail and holy shit you could add a lot of power and/or pull a bunch of weight on non-R7s :rofl: Like...... a lot! The setups listed with RRs could also be subbed out for RC1v2, but I have no idea if they're actually faster than RRs(doubtful?) and less contingency. It'd be cool if Toyo came out with a new compound and kept these silly mod factors for them :giggle:

Here are some ratios I looked at.....

2551lbs 205 R7s on 15x8.5
ratio:14.6
avg HP: 174.72
-0.7 A-arm
+0.2 mech TB
-0.2 non-OEM brakes
-0.2 comp weight
+0.3 226mm tire on 2400-2750lb car


2551lbs 225 RT660 on 15x9
ratio: 13.6
avg HP: 187.57
-0.7 A-arm
+0.2 mech TB
-0.2 non-OEM brakes
-0.2 comp weight
+0.3 226mm tire on 2400-2750lb car
+1.0 tire mod

2551lbs 225 RR on 15x9
ratio: 13
avg HP: 196.23(this is damn near my avg hp in TT4 trim on R7s!!!!)
-0.7 A-arm
+0.2 mech TB
-0.2 non-OEM brakes
-0.2 comp weight
+0.3 226mm tire on 2400-2750lb car
+1.6 tire mod

2490lbs 225 RT660 on 15x9
ratio: 13.7
avg HP: 181.02(this is my avg hp of my GLTC tune and 90lbs heavier than my 2022 GLTC weight)
-0.7 A-arm
+0.2 mech TB
-0.2 non-OEM brakes
-0.2 comp weight
+0.3 226mm tire on 2400-2750lb car
+1.0 tire mod

2451lbs 225 RR on 15x9
ratio: 13.1
avg HP: 187.10
-0.7 A-arm
+0.2 mech TB
-0.2 non-OEM brakes
-0.2 comp weight
+0.3 226mm tire on 2400-2750lb car
+1.6 tire mod

2401 225 RR on 15x9
ratio: 13.2
avg HP: 181.89
-0.7 A-arm
+0.2 mech TB
-0.2 non-OEM brakes
-0.2 comp weight
+0.3 226mm tire on 2400-2750lb car
+1.6 tire mod

I'm a lurker here, but building my car to ST rules for 2022. These changes pushed me pretty hard to ST6 instead of ST5. ST5 rules make the car so much more expensive for a BP miata build with either a very well built BP and hoosiers, or a bleeding edge built BP with RRs. K swap seems to be the answer and might be for me in the future if ST5 ever picks up steam in Rocky Mountain region.

Yup. The extra 5K you spend for the Kswap is made up for in reduced tears when the shfancy BP wears out or breaks. The BP would also have no headroom where the K24 can actually be detuned for ST5 leaving you with a >210whp high power map for hooning.

If I am reading this correctly under update backdate, a VVT 6 speed swap (01-05 drivetrain) into an NA chassis is ineligible for TT6. Sucks if this is the case.

6.2: Because the definition of “OEM” is any part that comes from the vehicle manufacturer either as a standard feature, a factory option, or on a factory optional trim model/package of that generation of the street-legal (in the U.S.A.) version of the vehicle, a vehicle may be updated or backdated with such parts without a Modification Factor assessment (applies to those items that would otherwise be assessed one).

For a time NASA viewed the 09-05 Miata all as "one generation" regarding brake upgrades. Not sure if that's still the case.

If the engine comes from a car also eligible for TT6, and the transmission came attached to that engine, you're good.
That is an extremely common setup and not even a grey area.

In this context the OEM update/backdate allowance covers it, yea.

NASA ST5/TT5:

I think the 1.6 credit category tires finally have enough of a handicap to win almost anywhere in TT. ST still seems to be Hoosier's domain due to the heat soak and inability to choose when you push/conserve to mange tire heat due to mixed class traffic.
Several folks have been setting TT5 records on the new Maxxis RC1R2 this year.
However, I still have two sets of 225/45/15 R7 stickers to burn up, sell or trade...

Constants of the build:
+.3 mechanical throttle body
-.5 having Aarms
+0 airdam/wing only, no splitter, no BTM
+0 allowed a control arm for camber adjustability now, but still using mod-free offsets, no ELBJs.

What I think is now option A:
2403lbs
182 avg hrspwrs
-.4 weight factor
+.3 "small tire credit" running a 226mm template at >2400lbs.
+1.6 Toyo RR/Maxxis RC1r2

Option B:
2450lbs
187avg whp
-.3 weight factor
+.3 "small tire credit" running a 226mm template at >2400lbs.
+1.6 Toyo RR/Maxxis RC1r2

Option C:
2460lbs
164avg whp
-3 weight factor
+0 225/45/15 Hoosier R7 on 9.5/10" wheel