When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
This thread will start with about a year of catch-up.
I've long daydreamed with an idea for an SCCA STR and NASA TTE dual duty streetcar. Something along the lines of 949/SPM's "Buttercup"
NASA has since replaced PT with ST, so the rules are a bit different. Some better, some worse.
The rules overlapped well, and allowed enough modifications for a really fun/quick car that 'might' still be wifey approved. It would never keep up with 'real' STR cars at a regional SCCA event, but it should play really well at locals and non-SCCA clubs.
My first attempt was doomed from the start when I picked up Scully, an 03 Club Sport. It was turrible on the street with no AC/Cruise and manual steering. I sold it after not very long.
Turtle is the opposite, a loaded LS w/Sport pkg.
I was initially looking for something in typical midwest condition to tool around in last winter after moving to OH from CA, so as to not put my rust free Land Cruiser through a salty winter. I ended up with a rust free southern car that had spent at least the last handful of years in KY. oops
The car has some MT.net history, being passed around a group of the KY Crew. Therefore, it had some decent parts on it already and a good mechanical history.
It has no Appearance Package, so fits the NASA ST/TT6 "BTM Aero" rule.
It already has a Racing Beat header/exhaust, RoadsterSport catted midpipe and an Injen intake.
500/300 DiY Billys with extended hats and glued isolators.
I traded the seller a set of new 15x9 Konig Dekagrams at a discount for his et20 15x8 FFDs to rid his garage of poverty spec 8"/205 stuff, and because I'm a ricer who likes the fitment.
First order of business was pulling the carboGloc race pads off and putting something more street friendly on. I went with the Stoptech 309 Sport pads and fresh centric blanks. I actually grew to love this pad and it has become my favorite dual duty track/TT/street pad. More on that later.
While I was in there, I lowered the front for scene points and to remove the reverse rake. I also weighed it and corner balanced it for grins, but seem to have lost that 26xxlb scale photo.
2020 is when the fun starts.
Covid meant the season getting delayed, so Button stayed on jackstands until July. Local autocross got going quite a bit earlier, so Turtle was put into duty.
Changes to the car were minor, initially. I removed the 'splitter' and replaced it with an ebay RS Active lip replica and picked up a set of 9" 6ULs w/225 RS4.
The 500/300 billies(above) were really nice on the street, but I had the 900/500 Xidas back in my possession after removing them from Tia. Another decision caused by COVID, was Tia being demoted from NASA TT6 duty.
Autocross on the Xidas was much more composed, and I was able to set FTD.
I received an offer for the Tungsten 6ULs that i couldn't refuse, so the RS4s moved to a set of the new blingy Konig Countergrams
The hardtop on this car was OEM Silver, and the trim was not removed during the repaint. At some point, it fell off, leaving a nice silver border around the hardtop. It doesn't pop in photos, but man does it burn my eyes in real life.
So it got fixed.
Repair turned upgrade opportunity when the fuel pump died. In went a DW100 for future e85/flexfuel abilities.
I've been hanging onto a set of MemoryFab UltraLow sliding seat rails for a decade now, and finally had a dual duty/streetcar worth putting a seat in. NB2 door panels kept me from fitting a Sparco QRTR, so I searched for months for a Recaro, Pole Position or SPG like this one.
July and early August were about when local track days/races started getting back on schedule. So Button went to NASA Pitt Race in ST5 and Gridlife GLTC at Mid Ohio.
More #buttonstuff in the other thread, but i'm posting these for the color, which is relevant later.
A couple good events in that car had me wanting to chillax a bit for the next event. For 6 years running now, NASA Great Lakes has held an event on my birthday weekend in late August at Mid Ohio. I decided to go record poaching since the Club Course record was soft(NASA Championships last year did not use this layout)
Turtle at this point still has oem rubber bushings and lines(clutch/brake), no additional front camber, and is fully equipped. I took it for a dyno and #sentit into TT6.
It made 132.08 on 93 with an Injen intake, squaretop, racing beat header, roadstersport catted midpipe and racing beat muffler.
That wasn't nearly enough to offset the NB2 LS thiccness, so I added some stickers for additional horsepressures:
Mid Ohio was awesome.
Was able to come away with wins on both layouts, and the Sunday win meant a new Track Record on the Club Course, taking it from the 2019 Champ runner-up.
1:42.9 on the Pro course
1:43.753 Club Course
Between car prep and conditions(rain all day friday into saturday morning meant a totally green track) Turtle is about 2 seconds off class-max pace here.
A lower rear gear, an OsGiken, 8-12 more whp, bearings/bushings, major weight loss and ballast placement, etc would all add up.
I don't think it was under 2530lbs(at 125 NASA avg horsepower) all weekend even with everything easily removed being removed, up to the OEM front shock tower brace.
The Stoptech Sport pads were initially terrible. They faded HARD lap two session 1 into T3 and I immediately took to limping it back to the pits. By the time I got around half the track, the pedal was back, so I did another lap at about 75% into the brake zones. I was able to again fade them, but they were getting better. Either my 'enthusiastic' street bedding and occasional autocross wasn't enough to bed them, or my daily driving wore off the transfer layer they need to work at track temp. GLoc's dont have this issue, I have been able to street drive R8/R10 without losing that transfer layer. By session 3 saturday, the brakes were driveable, but I had to pulse the thermal loads with a cooldown lap after a second flyer attempt. By Sunday, they were rock solid and have remained so.
A week or two later was the season finale for AutoInterests, a local HPDE org. I went up on a Monday and played instructor and bump drafted with my buddy Will in his NA8 SpecMiata.
I ran this event on the 245/40/15 Toyo RR from Button, so the car looked real sweet on big wheels.
Rear fenders are rolled flat, but front fenders are 100% stock in these photos. At some point it would catch the front lip during an incident were I was forced to add some opposite lock to catch a slide. You can see that in the photo. Following this event, the liners got trimmed, tabs bent back and fronts rolled flat as well. It hasn't rubbed anything since.
On the 245 Toyo RR I was able to squeeze out a 1:46.2 on Club Course with a passenger. That is ~2.5 seconds off pace compared to a 205 R7, but with 250lbs of passenger ballast in addition to the slower tires. No hard science there, but it would be tough to cover that spread with the minuscule .6 p:w credit the ST/TT5-6 rules give us.
Last event on the calendar was the NASA Great Lakes season finale at NCM (National Corvette Museum Motorsports Park)
With the Mid Ohio record taken, though still quite soft, I decided I wanted to throw a bit more prep at the car with the hopes of making the NCM record, should I achieve it, last a little longer. I once held the TTE record, but Kopitski(future Champ) took it the following year in Bubbles(the fastest E car ever built, 949/SPM aborted project).
My options were:
A. Buy horsepower ($1400 MS3Pro, $200 wideband, e85) and re-dyno ($150)
B. Remove weight.
This car is still my daily driver, so I didn't want to do the whole slew of power steering, cruise control, air conditioning deletes. It already had the softtop, passenger seat, front shock tower bar and all trunk junk removed, as well as a 3lb Deka battery.
The easy picking were the hardtop and trailer hitch. If I was going to put Button's livery wrapped top on the car, why wouldn't I also move the vented hood and skinned trunk?
The results:
Hood/top/trunk moved over. Hitch removed. With an empty tank and a morning poop, it could potentially reach the 2450lb mark(with 190lb driver)on 205 Hoosiers and 9" 6ULs. These 225/45 Falken RT660s on 9" Dekagrams(pictured) were 3.5lbs heavier per corner, most of that from tire weight differences as the wheels are within a pound of each other(6ULs lighter)
This hood is gutted, no latch loop assembly, but has 5 aluminum vents rivetted to it. It 'felt' lighter during the swap, but no conclusive data. Either way, the aero beni and cool(ing) factor were worth it.
The top is WAY lighter. My OEM top is defrost/headliner and my race top is 15lbs total CCP/lexan. This is the big chunk of weight loss, followed by the hitch.
Trunk might be 2lbs lighter from webbing delete and brake light delete, maybe.
At 2450lbs it is still missing 7 average WHP, or about 10 peak. I think that(2456/132avg) is the on-paper best Miata for ST/TT6 for most tracks. Some places you could add 100lbs for the next ratio credit(2554/138), but I am killing hubs with regularity over 2500lbs on Hoosiers(both cars) and really just don't like the 'feel' of these cars up there. My PTE/TTE championship car was over 2500lbs, Button is over 2500 in ST5 and this car was nearly 2600 early on. My favorite Miatas to drive have been Button in 2250lb/143hp ST5 spec and Taxi at ~2180/160whp GTA Street spec.. They are just so much more "fun" below 2300lbs, but at 18:1 P:W, they can't get out of their own way that light(2301/123)
its reassuring to knows that weight savings can be accomplished and still keep most of its trim. I'd love to get a lightweight hardtop to take a majority of the weight out with one purchase, but that will have to wait till next year.
Solid weekend with NASA Great Lakes. National Corvette Museum Motorsports Park is awesome, and I get reminded that it’s a top two track in the Midwest every time I make the trip. It’s a 7 hour tow with fuel stops and stuff, but so worth it.
It was awesome to see the out-of-state MT.net homie and previous, previous, previous Turtle owners Jeff and Wes and put a few faces to new internet names and customers.
The Midwest Miata Parts team was in pretty full force as always.
I was able to drop a couple whole seconds in Turtle compared to Tia a year ago, and even ended up a tenth quicker than my 2016 TTE track record. This means literally nothing for class pace, as all three cars are/were pretty under-developed. The TTE record got beat the year after I moved to CA, it didn't stand for long.
Friday mid afternoon arrival. Started raining during the TREC enduro race, and continued most of the evening and into Sat morning.
Saturday: Rain until ~9am. Wet track until ~10:30. I ran 225/45/15 Falken RT660s for the wet warmup and what turned out to be dry but green TT#1. I threw on the 205/50/15 R7s for TT#2
I got video, but the cloudy weather had my AIM all sorts of freaked out, about a quarter second off compared to the transponder all weekend. I left it connected to my laptop in the garage during TT session #2 just before lunch, which ended up the best weather session on Saturday. I would love a fully dry event next time, as it rains literally every time I go to NCM. Mist turned to sprinkles and more rain earl afternoon and the temp dropped quickly down to the low 50s. Gross.
Best lap on the Falkens was a 2:27.4(27.00 'rolling' lap)
Best lap on the Hoosiers was a 2:24.2(new track record)
Room for improvement on both, but I am not sure a .6 credit(4.39whp on this car) can close a 3 second gap(2% laptime delta). Ideally, at this weight, I'd run a 245/40/15 RR, or the upcoming CR1 or RT660 for 2021 to further cover the gap to the R7.
RT660 laps:
NCM TT6 Track Record:
-RF hub is dying, don't do what I do, shut it down and bring the car in. I risked it for this biscuit because it rained all morning, and ended up mist/sprinkling in the afternoon too. I HAD to bank a couple dry laps with a track layout change coming on day 2.
Sunday: New track layout for NASA GL, new track layout for me as well. Simple change from "Grand Full" to "Bike Loop" which simply deletes the "Sinkhole" and turns left from T18 onto the front straight drag strip.
I came home with two wins, two TT6 records(2:24.2 Grand Full and 2:11.8 Bike Loop) and a full set of contingency tires. Solid.
As a kicker, I was faster than both TT5 and TT4 all weekend, and spent a couple sessions 4/5th overall in the entire TT run group due to the wet weather. On Sunday, the entire TT5 field moved up a class or two to build contingency.
There is a 22.9 out there in this current version of Turtle, data shows it and I 'feel' it. I just need more than 3 laps on dry track and without an actively breaking car. The lightest I came in was 2467, which means I have nearly 8 average WHP left on the table still, which is about 12 peak. I think a 2450lb, 145 whp peak(138avg) BP4W 6/4.3 car on 225 R7s is potentially a 2:20.
Now it is time to prep it for sale. If anybody is looking for a GREAT turn-key HPDE car, a super competitive TT6 car or a really well sorted Kswap candidate, ST5/6, GLTC starter, etc.. share my info.
Button’s body panels came off, I replaced the front hubs, and I listed it for sale.
New owner several states away is going to keep using it as his daily and occasional HPDE with an eye towards Gridlife and potentially more NASA TT6. He wanted it in more of a streetcar-that-can-go-to-the-track guise rather than a track-car-that-is-livable-on-the-street guise.
So I put together a set of the new +35mm(no longer +25) 15x8 Konig Hypergram and 205/50/15 Conti ECS, removed the Recaro SPG, MOMO Mod 78 and the 3lb battery. Back in went the matching NA8 black cloth seat, oem NB wheel and an oem size battery.
Working AC, cruise, power steering, stereo, and full oem safety system. 900/500 Xida, 132whp through a squaretop and I/h/e. Mazdacomp engine mounts and oem rubber elsewhere. It’s a wonderful car again.
I'm curious to hear your thoughts on the 900 / 500 rates for those tires. My very limited knowledge says they would be a bit stiff for the grip you would generate on those. Are you planning on changing rates as it's more of a street car now, or keeping them and swapping to sticky's for track days, etc?
Sorry bby, i didn't mean to present that like your question was invalid.
I do have some relative DPE, though. This setup would make sense if new owner has a set of track wheels/tires to slam on for track days but doesn't want to deal with shittier manners during normal street car days. (Which ECS are great at)
Running ECS full time, i would not personally run these rates. They're comfy enough, but unecessary for the level of grip the ECS will ultimately generate.
DPE: i run 900/500 Xidas on my Miata with VR1s. Probably a bit overkill even for that, but i likes the taste. I run ECS on my S2000 with DFVs at whatever 10k/8k is in freedom units. It's a better match.
10-22-2020, 10:32 AM
"Turtle" NB2 street/AX/NASA TT6 project
0
It's been a long day, don't mind me [backs away slowly]
