NASA ST6/TT6
#102
edit
As long as we know these aren't official, I don't mind sharing.
205 R7 on 9" = 230mm @23mm.
205 SM7 on 9" = 236mm @ 30mm (FatKao)(My R7 was within 1mm at 30mm)
245 RC1 on 10”: 249mm @23mm. 254@30mm
245 Rival S on 9”: 242@23mm. 249@30mm
225 Sur4g on 9”: 228@23mm. 231@30mm.
225 RC1 on 9”: 225@23mm. 230@30mm.
205 R7 on 8 = 226mm @23mm. Meets “equal to” rule.
205 RR on 8 = 210mm@30mm (FatKao)
205 RE71R on 8”: 208@23mm
205 VR1 on 8”: 218@23mm
205 R7 on 9" = 230mm @23mm.
205 SM7 on 9" = 236mm @ 30mm (FatKao)(My R7 was within 1mm at 30mm)
245 RC1 on 10”: 249mm @23mm. 254@30mm
245 Rival S on 9”: 242@23mm. 249@30mm
225 Sur4g on 9”: 228@23mm. 231@30mm.
225 RC1 on 9”: 225@23mm. 230@30mm.
205 R7 on 8 = 226mm @23mm. Meets “equal to” rule.
205 RR on 8 = 210mm@30mm (FatKao)
205 RE71R on 8”: 208@23mm
205 VR1 on 8”: 218@23mm
Last edited by blkmkiii; 11-01-2018 at 09:44 PM.
#104
2019 rules are now official, no longer provisional.
The calculator is live. https://form.jotform.com/drivenasa/s...ification-form
A few more cars have been added in by Appendix.
Appendix C—Additional ST6 Eligible Vehicle Models The following vehicles are approved to compete in ST6 despite either an OEM HP or engine displacement greater than the listed maximum in Section 4. For the vehicles with engine displacement greater than 2449cc, no modifications to increase displacement are permitted. A 10cc variance from the factory displacement listing shall be permitted, but any vehicle inspected with greater than 10cc over the listed displacement below, shall be disqualified. Engines from these vehicles may only be used as a swap donor to ST6 eligible vehicles of the same model of a different year.
BMW E30 325 (’87-’91) (2494cc)
Ford Focus SVT (’02-’04) (2.0L, 170hp)
Nissan Sentra SE-R (’02-’06) (2489cc)
Nissan Sentra SE-R Spec V (’02-’06)(2489cc)
Porsche 924 S (’87-’88) (2479cc, 8 valve)
Porsche 944 (’83-’88) (2479cc, 8 valve)
Porsche 944 (’89) (2688cc)
Subaru Impreza RS (’98-’01) (2457cc) (AWD)
Subaru Impreza 2.5i (’08-’11)(2457cc) (AWD)
The calculator is live. https://form.jotform.com/drivenasa/s...ification-form
A few more cars have been added in by Appendix.
Appendix C—Additional ST6 Eligible Vehicle Models The following vehicles are approved to compete in ST6 despite either an OEM HP or engine displacement greater than the listed maximum in Section 4. For the vehicles with engine displacement greater than 2449cc, no modifications to increase displacement are permitted. A 10cc variance from the factory displacement listing shall be permitted, but any vehicle inspected with greater than 10cc over the listed displacement below, shall be disqualified. Engines from these vehicles may only be used as a swap donor to ST6 eligible vehicles of the same model of a different year.
BMW E30 325 (’87-’91) (2494cc)
Ford Focus SVT (’02-’04) (2.0L, 170hp)
Nissan Sentra SE-R (’02-’06) (2489cc)
Nissan Sentra SE-R Spec V (’02-’06)(2489cc)
Porsche 924 S (’87-’88) (2479cc, 8 valve)
Porsche 944 (’83-’88) (2479cc, 8 valve)
Porsche 944 (’89) (2688cc)
Subaru Impreza RS (’98-’01) (2457cc) (AWD)
Subaru Impreza 2.5i (’08-’11)(2457cc) (AWD)
#105
Break points and notable items:
Weight Factors.
<2250 is -.5
2250-2449 is -.4
2450-2549 is -.3
2550-2649 is -.2
Section width/wheel size.
2400lbs opens up the 257mm template. This allows a 205 or 225 Hoosier on 9" wheel, and pretty much every 80-200tw tire in existence.
Raw ratio(easier "raceability" with more raw power and a better ratio)
2250/120 is 18:1 after Aarms and BTM aero. 18.75 raw.
2400/128 is 18:1 after Aarms and BTM aero. 18.75 raw. 9" wheel
2450/131 is 18.1:1 after Aarms and BTM aero. 18.70 raw.
2455/132 is 18:1 after Aarms and BTM aero. 18.60 raw. (Sweet spot IMO. Easy for a healthy stock NB motor with bolt ons.)
2555/138 is 18:1 after Aarms and BTM aero. 18.51 raw.
2555 would be tough to hit without serious forethought and zero weight removal. Ballast rule prohibits simply bolting in 400lbs of steel plate, so you'd have to do things like use full OEM doors, glass windshields, full dash, carry an airbag, OEM hardtop top, etc. Which kills the Cg and polar moment.
Weight Factors.
<2250 is -.5
2250-2449 is -.4
2450-2549 is -.3
2550-2649 is -.2
Section width/wheel size.
2400lbs opens up the 257mm template. This allows a 205 or 225 Hoosier on 9" wheel, and pretty much every 80-200tw tire in existence.
Raw ratio(easier "raceability" with more raw power and a better ratio)
2250/120 is 18:1 after Aarms and BTM aero. 18.75 raw.
2400/128 is 18:1 after Aarms and BTM aero. 18.75 raw. 9" wheel
2450/131 is 18.1:1 after Aarms and BTM aero. 18.70 raw.
2455/132 is 18:1 after Aarms and BTM aero. 18.60 raw. (Sweet spot IMO. Easy for a healthy stock NB motor with bolt ons.)
2555/138 is 18:1 after Aarms and BTM aero. 18.51 raw.
2555 would be tough to hit without serious forethought and zero weight removal. Ballast rule prohibits simply bolting in 400lbs of steel plate, so you'd have to do things like use full OEM doors, glass windshields, full dash, carry an airbag, OEM hardtop top, etc. Which kills the Cg and polar moment.
#109
Weeeeelp I didn't do any ST/TT5 prep OR acquire truck/trialer/SM, so looks like I'm just gonna run TT6 for first event. Just going to run what I already have. Should end up somewhere around...
2450/130avg (don't have txt file yet)
-.7 a-arm
-.3 weight
-.2 ELBJ
+.4 BTM aero
= 18.05
Running over 2400lbs can keep SM7s on 9's. Throwing the RB/SuperMiata sways back on along with steering rack spacers and either gonna drop front rate to 800 (400r) or bring rear back up to 500 (1000f). 400 rear rides a whoooole lot better on the street so kinda leaning towards 800/400 and if it's terribad udersteer on track I can always swap springs around. On 93 not a whole lot different than my TTE* setup, just add 20lbs and get sways back. On TTE* e85 tune I'd be closer to 133avg and full power 135avg, so more weight, but I don't feel like going through the hassle of getting e85 anyways.
2450/130avg (don't have txt file yet)
-.7 a-arm
-.3 weight
-.2 ELBJ
+.4 BTM aero
= 18.05
Running over 2400lbs can keep SM7s on 9's. Throwing the RB/SuperMiata sways back on along with steering rack spacers and either gonna drop front rate to 800 (400r) or bring rear back up to 500 (1000f). 400 rear rides a whoooole lot better on the street so kinda leaning towards 800/400 and if it's terribad udersteer on track I can always swap springs around. On 93 not a whole lot different than my TTE* setup, just add 20lbs and get sways back. On TTE* e85 tune I'd be closer to 133avg and full power 135avg, so more weight, but I don't feel like going through the hassle of getting e85 anyways.
#111
Thought the consensus, even with sways, was to add a bit more spring up front for hoosiers? Aren't you guys shooting for 900/500 with a the 1.6? I ran 800/500 out of the box, definitely works just fine so could definitely start there. Other than stock sways I really like how 1000/400 feels b/c it basically never tries to step out unless over doing it, super stable.
#112
You're adding a ton of front roll stiffness if you go RB front bar and 1000. My car is that way, and is tight even with a 4" splitter and the wing trimmed out with no gurney.
The SPM S2 I raced last had a standard BGK with 800/500 and 1.125"/14mm bars. It was stellar. Better balance than my 1000/500 car.
By all means play around and test. Run what you like.
The SPM S2 I raced last had a standard BGK with 800/500 and 1.125"/14mm bars. It was stellar. Better balance than my 1000/500 car.
By all means play around and test. Run what you like.
#114
The general recommendations are all good and well, but if 800/500 is best for no aero / 205 hoosier why is Miller spec'd for an extra 100lbs up front with a lighter motor? I also have A/C, so even an extra bit of weight in the wrong places up front. I had no real intention of running 1000lbs with the RB sway, I really don't want to as it blows on the street with that combo and would be overly stiff on our more bumpy tracks for sure, just an inquisitive question.
Rear springs are silly easy to change, so I think I'll just try 800f and both 500/400 rear to satisfy my curiosity and exercise in futility.
Rear springs are silly easy to change, so I think I'll just try 800f and both 500/400 rear to satisfy my curiosity and exercise in futility.
#115
The general recommendations are all good and well, but if 800/500 is best for no aero / 205 hoosier why is Miller spec'd for an extra 100lbs up front with a lighter motor? I also have A/C, so even an extra bit of weight in the wrong places up front. I had no real intention of running 1000lbs with the RB sway, I really don't want to as it blows on the street with that combo and would be overly stiff on our more bumpy tracks for sure, just an inquisitive question.
Rear springs are silly easy to change, so I think I'll just try 800f and both 500/400 rear to satisfy my curiosity and exercise in futility.
Rear springs are silly easy to change, so I think I'll just try 800f and both 500/400 rear to satisfy my curiosity and exercise in futility.
In any case spring rate recommendations are not written in stone. Every driver has their own preference.
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#116
You're comparing a race car built to win nationals to your street car ride quality requirements. Even with a B6, It's still a heavy in b. That brings a significant roll and pitch moment. Beyond that Sonny and I simply both prefer the feel of the stiffer front springs.
In any case spring rate recommendations are not written in stone. Every driver has their own preference.
In any case spring rate recommendations are not written in stone. Every driver has their own preference.
The driver preference is what I was looking for, really. I thought maybe that was the case, but didn't know if there was some more technical reason. Thanks! Always appreciate the insight from you and team.
#117
I didn't suggest a compromise, you did. You were concerned with ride quality. "Blows on the street". Indicating you like the way it handled but did not like the ride quality on the street therefore you made a compromise. Personal preference. We have met drivers who feel that 450/300 is too stiff and others who like 1000/500 on their daily.
In any case, Miller will be a new case study for us as we have never built anything quite like it. Our 2013 Runoffs NB6 was something like 2150lbs/146whp, 3" splitter and APR GTC-200 (spec). S2's, lighter w more power and a BP.
In any case, Miller will be a new case study for us as we have never built anything quite like it. Our 2013 Runoffs NB6 was something like 2150lbs/146whp, 3" splitter and APR GTC-200 (spec). S2's, lighter w more power and a BP.
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