Running the SPB in other series
#31
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The Toyo RR is actually a DOT radial
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Todd Lamb
Atlanta Speedwerks
www.ATLspeedwerks.com
Porsche repairs, servicing, and upgrades / Certified IMS installer / PDK repair experts
Over 150 PDK's repaired and counting: https://youtu.be/m54P_zisEcI
Todd Lamb
Atlanta Speedwerks
www.ATLspeedwerks.com
Porsche repairs, servicing, and upgrades / Certified IMS installer / PDK repair experts
Over 150 PDK's repaired and counting: https://youtu.be/m54P_zisEcI
#32
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Considering running my Spec Boxster in NASA GTS 2 or SCCA T3 next year. Hoosier R7s seem to be required for competitive times in those classes. Looking at the Hoosier specs the 245 x 40 x17 is 1.4" less diameter than the Toyo 255. But the 245 x 45 x 17 is only .2" less and would seem to be the better choice.
Todd when you ran the 225's at the runoffs did it create any ground clearance issue with a deep sump? or did the lower gearing help acceleration?
Todd when you ran the 225's at the runoffs did it create any ground clearance issue with a deep sump? or did the lower gearing help acceleration?
#33
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Considering running my Spec Boxster in NASA GTS 2 or SCCA T3 next year. Hoosier R7s seem to be required for competitive times in those classes. Looking at the Hoosier specs the 245 x 40 x17 is 1.4" less diameter than the Toyo 255. But the 245 x 45 x 17 is only .2" less and would seem to be the better choice.
Todd when you ran the 225's at the runoffs did it create any ground clearance issue with a deep sump? or did the lower gearing help acceleration?
Todd when you ran the 225's at the runoffs did it create any ground clearance issue with a deep sump? or did the lower gearing help acceleration?
#34
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Originally Posted by Slade
Considering running my Spec Boxster in NASA GTS 2 or SCCA T3 next year. Hoosier R7s seem to be required for competitive times in those classes. Looking at the Hoosier specs the 245 x 40 x17 is 1.4" less diameter than the Toyo 255. But the 245 x 45 x 17 is only .2" less and would seem to be the better choice.
Todd when you ran the 225's at the runoffs did it create any ground clearance issue with a deep sump? or did the lower gearing help acceleration?
Todd when you ran the 225's at the runoffs did it create any ground clearance issue with a deep sump? or did the lower gearing help acceleration?
#35
Rennlist Member
Todd - you think the SPB is nationally competitive in T3 from your race there or just circumstance / skill differential that put you up front
given NorCal location this year contemplating running the nationals a a few super tours to qualify
given NorCal location this year contemplating running the nationals a a few super tours to qualify
#37
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A bit of idle curiosity on this topic for local races. I was talking with a local race shop yesterday. It looks like there may be a bigger showing in my local track's NASA ST4 class than GTS2, and I was wondering about running the car in ST4 if I found myself the only GTS2 entrant on a race day. ST4 allows a 12:1 weight to power ratio, and a SPB is close to the GTS2 level of 14.5:1.
I could always just throw an ST4 sticker on the car and get killed. Even running light at 2600 lbs, 220RWHP over the last 1000-1500 RPMs is allowed, and the strongest SPBs peak at ~190whp. But lots of SPB restrictions disappear in ST4. So what could be expected from a quick and easy ST class change? Thinking of something simple and cheap like eBay headers plus a flashed ECU - would that be enough to expect 210 whp peak? That wouldn't be very competitive but might still be enough to keep up and have a good time.
And maybe I'm forgetting about some boat anchor we have hiding in these cars that could be easily removed for NASA ST/GTS events. At ~2500 lbs with Hoosiers and ~210whp it might actually be competitive...
I could always just throw an ST4 sticker on the car and get killed. Even running light at 2600 lbs, 220RWHP over the last 1000-1500 RPMs is allowed, and the strongest SPBs peak at ~190whp. But lots of SPB restrictions disappear in ST4. So what could be expected from a quick and easy ST class change? Thinking of something simple and cheap like eBay headers plus a flashed ECU - would that be enough to expect 210 whp peak? That wouldn't be very competitive but might still be enough to keep up and have a good time.
And maybe I'm forgetting about some boat anchor we have hiding in these cars that could be easily removed for NASA ST/GTS events. At ~2500 lbs with Hoosiers and ~210whp it might actually be competitive...
#38
Drifting
Looks like there is a new class ST5 -- 14:1 WPR --
Seems like that would be an easier fit.
I don't know all the adjustments for a SPB -- here are the rules
https://nasa-assets.s3.amazonaws.com...5--3-21-18.pdf
Mike
Seems like that would be an easier fit.
I don't know all the adjustments for a SPB -- here are the rules
https://nasa-assets.s3.amazonaws.com...5--3-21-18.pdf
Mike
#39
Rennlist Member
Looks like there is a new class ST5 -- 14:1 WPR --
Seems like that would be an easier fit.
I don't know all the adjustments for a SPB -- here are the rules
https://nasa-assets.s3.amazonaws.com...5--3-21-18.pdf
Mike
Seems like that would be an easier fit.
I don't know all the adjustments for a SPB -- here are the rules
https://nasa-assets.s3.amazonaws.com...5--3-21-18.pdf
Mike
I checked that out in more detail... they've made some updates to the ST5 rules in the last few months and the car looks a lot more competitive now than it did in December. Very interesting. I wonder how full this class will be locally.
Super Touring 5 (ST5) = “Adjusted Wt/HP Ratio” equal to, or greater than, 14.00:1
-Average horsepower is the average horsepower in the top 1750 RPMs of the dyno chart (for a SPB), and 180-185 seems to be a reasonable or slightly strong number for a SPB
-Tires are any DOT tire in up to 245 width if the car is at 2750+ lbs and 225 for 2400-2750 lbs (though this uses a physical NASA width measurement to compensate for tires that have a narrow stated width compared to real width)
-Up to 250 lbs of ballast is permitted
Base power to weight for a typical SPB at minimum weight will probably be 2650 lbs and ~183NASAwhp
2650/183=14.5
**This means a modification factor of 0.1 is worth 18.3 lbs of weight (reduction or ballast)
I suspect the modification factors for most everyone would be:
+0.5 = -92 lbs : Adjust 14.5:1 ratio to allowed 14.0:1
-0.5 = +92 lbs : Replace, modify, or remove control arms, camber arms/links, toe arms/links
-0.7 = +128 lbs : Non-OEM shocks/struts with shaft diameter 40mm or greater
-0.4 = +73 lbs : Rear-Mid or Rear engine layout (not Front-Mid)
__________
Total ballast or car weight would be +201 lbs from the spec minimum, so 2850 lbs which makes the -0.1 weight modification factor not apply but only barely - fuel level would have to be monitored
Also a bit more that could apply to some cars and/or regions:
-0.1 = +18 lbs : weight less than 2850 but more than 2650 lbs
-0.3 = +55 lbs : (Many SPBs) One or more cage bars that penetrate the front bulkhead/firewall
+0.4 = -73 lbs : (Spoiler down and negotiate with scruts) Base Trim Model Aero - this is only for cars with no factory spoiler or wing but exceptions exist for when the spoiler is removed
So basically, a SPB that is about 200 lbs overweight and running on 225 or 245 Hoosiers (I know they run wide so their 245 may be too wide) could compete in ST5 and be right at the class limit. The spec RRs could possibly work but it's more likely they will exceed the maximum NASA tread width and be illegal. I'll have to watch this class as well as GTS2. Some are suggesting ST and GTS be merged, but I think most of those folks making the suggestion don't run German cars...
Super Touring 5 (ST5) = “Adjusted Wt/HP Ratio” equal to, or greater than, 14.00:1
-Average horsepower is the average horsepower in the top 1750 RPMs of the dyno chart (for a SPB), and 180-185 seems to be a reasonable or slightly strong number for a SPB
-Tires are any DOT tire in up to 245 width if the car is at 2750+ lbs and 225 for 2400-2750 lbs (though this uses a physical NASA width measurement to compensate for tires that have a narrow stated width compared to real width)
-Up to 250 lbs of ballast is permitted
Base power to weight for a typical SPB at minimum weight will probably be 2650 lbs and ~183NASAwhp
2650/183=14.5
**This means a modification factor of 0.1 is worth 18.3 lbs of weight (reduction or ballast)
I suspect the modification factors for most everyone would be:
+0.5 = -92 lbs : Adjust 14.5:1 ratio to allowed 14.0:1
-0.5 = +92 lbs : Replace, modify, or remove control arms, camber arms/links, toe arms/links
-0.7 = +128 lbs : Non-OEM shocks/struts with shaft diameter 40mm or greater
-0.4 = +73 lbs : Rear-Mid or Rear engine layout (not Front-Mid)
__________
Total ballast or car weight would be +201 lbs from the spec minimum, so 2850 lbs which makes the -0.1 weight modification factor not apply but only barely - fuel level would have to be monitored
Also a bit more that could apply to some cars and/or regions:
-0.1 = +18 lbs : weight less than 2850 but more than 2650 lbs
-0.3 = +55 lbs : (Many SPBs) One or more cage bars that penetrate the front bulkhead/firewall
+0.4 = -73 lbs : (Spoiler down and negotiate with scruts) Base Trim Model Aero - this is only for cars with no factory spoiler or wing but exceptions exist for when the spoiler is removed
So basically, a SPB that is about 200 lbs overweight and running on 225 or 245 Hoosiers (I know they run wide so their 245 may be too wide) could compete in ST5 and be right at the class limit. The spec RRs could possibly work but it's more likely they will exceed the maximum NASA tread width and be illegal. I'll have to watch this class as well as GTS2. Some are suggesting ST and GTS be merged, but I think most of those folks making the suggestion don't run German cars...
#40
Drifting
I checked that out in more detail... they've made some updates to the ST5 rules in the last few months and the car looks a lot more competitive now than it did in December. Very interesting. I wonder how full this class will be locally.
Super Touring 5 (ST5) = “Adjusted Wt/HP Ratio” equal to, or greater than, 14.00:1
-Average horsepower is the average horsepower in the top 1750 RPMs of the dyno chart (for a SPB), and 180-185 seems to be a reasonable or slightly strong number for a SPB
-Tires are any DOT tire in up to 245 width if the car is at 2750+ lbs and 225 for 2400-2750 lbs (though this uses a physical NASA width measurement to compensate for tires that have a narrow stated width compared to real width)
-Up to 250 lbs of ballast is permitted
Base power to weight for a typical SPB at minimum weight will probably be 2650 lbs and ~183NASAwhp
2650/183=14.5
**This means a modification factor of 0.1 is worth 18.3 lbs of weight (reduction or ballast)
I suspect the modification factors for most everyone would be:
+0.5 = -92 lbs : Adjust 14.5:1 ratio to allowed 14.0:1
-0.5 = +92 lbs : Replace, modify, or remove control arms, camber arms/links, toe arms/links
-0.7 = +128 lbs : Non-OEM shocks/struts with shaft diameter 40mm or greater
-0.4 = +73 lbs : Rear-Mid or Rear engine layout (not Front-Mid)
__________
Total ballast or car weight would be +201 lbs from the spec minimum, so 2850 lbs which makes the -0.1 weight modification factor not apply but only barely - fuel level would have to be monitored
Also a bit more that could apply to some cars and/or regions:
-0.1 = +18 lbs : weight less than 2850 but more than 2650 lbs
-0.3 = +55 lbs : (Many SPBs) One or more cage bars that penetrate the front bulkhead/firewall
+0.4 = -73 lbs : (Spoiler down and negotiate with scruts) Base Trim Model Aero - this is only for cars with no factory spoiler or wing but exceptions exist for when the spoiler is removed
So basically, a SPB that is about 200 lbs overweight and running on 225 or 245 Hoosiers (I know they run wide so their 245 may be too wide) could compete in ST5 and be right at the class limit. The spec RRs could possibly work but it's more likely they will exceed the maximum NASA tread width and be illegal. I'll have to watch this class as well as GTS2. Some are suggesting ST and GTS be merged, but I think most of those folks making the suggestion don't run German cars...
Super Touring 5 (ST5) = “Adjusted Wt/HP Ratio” equal to, or greater than, 14.00:1
-Average horsepower is the average horsepower in the top 1750 RPMs of the dyno chart (for a SPB), and 180-185 seems to be a reasonable or slightly strong number for a SPB
-Tires are any DOT tire in up to 245 width if the car is at 2750+ lbs and 225 for 2400-2750 lbs (though this uses a physical NASA width measurement to compensate for tires that have a narrow stated width compared to real width)
-Up to 250 lbs of ballast is permitted
Base power to weight for a typical SPB at minimum weight will probably be 2650 lbs and ~183NASAwhp
2650/183=14.5
**This means a modification factor of 0.1 is worth 18.3 lbs of weight (reduction or ballast)
I suspect the modification factors for most everyone would be:
+0.5 = -92 lbs : Adjust 14.5:1 ratio to allowed 14.0:1
-0.5 = +92 lbs : Replace, modify, or remove control arms, camber arms/links, toe arms/links
-0.7 = +128 lbs : Non-OEM shocks/struts with shaft diameter 40mm or greater
-0.4 = +73 lbs : Rear-Mid or Rear engine layout (not Front-Mid)
__________
Total ballast or car weight would be +201 lbs from the spec minimum, so 2850 lbs which makes the -0.1 weight modification factor not apply but only barely - fuel level would have to be monitored
Also a bit more that could apply to some cars and/or regions:
-0.1 = +18 lbs : weight less than 2850 but more than 2650 lbs
-0.3 = +55 lbs : (Many SPBs) One or more cage bars that penetrate the front bulkhead/firewall
+0.4 = -73 lbs : (Spoiler down and negotiate with scruts) Base Trim Model Aero - this is only for cars with no factory spoiler or wing but exceptions exist for when the spoiler is removed
So basically, a SPB that is about 200 lbs overweight and running on 225 or 245 Hoosiers (I know they run wide so their 245 may be too wide) could compete in ST5 and be right at the class limit. The spec RRs could possibly work but it's more likely they will exceed the maximum NASA tread width and be illegal. I'll have to watch this class as well as GTS2. Some are suggesting ST and GTS be merged, but I think most of those folks making the suggestion don't run German cars...
I'll have to check out my cage to see if those modifications come into play.
Good to know tho -- as there aren't many PCA races in Texas anymore -- so I was looking to haul 8 hours minimum to get more than 2 races in.
Mike
#41
Drifting
delete
#43
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The SPB was competitive in T3 when we first got it classified in 2017, but T3 has suffered from rules creep and the lap times are far past where SPB is able to be competitive. You can find all the specifics on the tires/rules in the GCR spec lines for T3.
I don’t really see any way to make the SPB competitive in T3 these days without making drastic changes to the car that make it no longer a SPB or able to be converted back and forth. The best bet would be to campaign to have the car put in T4 with weight added but T4 doesn’t allow a lot of the SPB modifications so that’s a dead end.
However, to just get seat time and have fun, T3 is still a good option.
I don’t really see any way to make the SPB competitive in T3 these days without making drastic changes to the car that make it no longer a SPB or able to be converted back and forth. The best bet would be to campaign to have the car put in T4 with weight added but T4 doesn’t allow a lot of the SPB modifications so that’s a dead end.
However, to just get seat time and have fun, T3 is still a good option.
#44
Rennlist Member
Hey all
I’ve run my SPB with SCCA in the T3 class in 2022, and once in 2023 to keep my license alive. Going to be doing the same this year but would like to add a little more track time to the weekend.
I’ve been going over the GCR to understand if I can run an SPB in the ITR class. So far it appears that I can without modification, but curious if anyone else has done similar research? Failing that I think it can just class as STU.
I’m not concerned about competitiveness, it’s just for additional seat time.
Kris
I’ve run my SPB with SCCA in the T3 class in 2022, and once in 2023 to keep my license alive. Going to be doing the same this year but would like to add a little more track time to the weekend.
I’ve been going over the GCR to understand if I can run an SPB in the ITR class. So far it appears that I can without modification, but curious if anyone else has done similar research? Failing that I think it can just class as STU.
I’m not concerned about competitiveness, it’s just for additional seat time.
Kris
#45
Most of the SPB cars in Utah and Colorado that run NASA run in either GTS1 or ST5. They are not competitive in ST4 with E46 cars or in GTS2 with later Boxsters running larger motors (our GTS2 champ was in a later car with 3.2 motor). I did try the Hoosiers at UMC/Miller a few years ago and was 4 sec/lap faster! That may make us more competitive in ST5 too.