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.
First time racing here, as last year I only Time Trialed.
I am equipped with one set of used scrubs on narrow wheels from a customer's 2019 NASA Champs attempt.
I havent raced in 11 months.
Before the race, I took a freind's freshly built ST6 car out for a TT6 data lap and reset my own TT6 record from last year with a 2:04.4. (It was a procedural DQ since we did not team entry, I just ran the data lap with consent from the TT director)
I qualified on pole, but it was a battle going into T1 after getting rolled by Thai and all his RX8 torks. I was able to get back by, and build a gap early in the race. However, he and his 245/40/17s would later catch me again into T1 and execute a perfect over-under up the hill and take the lead into the 3/4 complex and cruise to victory. He raw timed me by 8 tenths for fastest lap late in the race.
Good things:
-Podium in the debut of Button v3 with a P2 in race #1
-Dramatically improved front aero/front downforce.
-Racing with 161whp is fun.
-Local field is fast(entire podium from 2019 Champs is in-region)
Bad things:
-off pace
-New front aero is lacking brake cooling.
-Used tires are old and used.
-I made multiple uncharacteristic mistakes after 11 months out of the drivers seat.
Tomorrow we race earlier and shorter, so hopefully I can keep the tires and brakes happy for the duration.
The biggest tuning change yesterday was adding more and more wing every session. I didn’t make that many changes to the car since the last race 11 months ago, but I did convert the suspension to bronze impregnated sleeve bearings inside the urethane bushings. (Super Touring rules require the bushings to be “majority” non-metallic, so traditional racecar spherical bearings are not allowed)
I expected that change to be felt on the whole chassis, and it definitely feels more supple and takes curbs even better than before. The other change was the the new front airdam having a smaller opening and being 100% sealed to the radiator. That was a shockingly powerful front downforce upgrade. I added rear wing angle three times in small steps each session and the car was DIALED in race 2 this morning. 1:57.3 was a tenth off the ST record Thai set and within .3 of Samed the TT5 king. I’m pretty pumped on that with 1 day of testing(yesterday) and used tires.
Tire setup data and wing adjustments allowed me to close the gap to Thai. Race #2 was the battle we both wanted, and I crossed the finish line first, but wildly miscalculated the fuel burn with all my new Keegan Engineering horsepressures. Post race tech resulted in a DQ for being under weight. This will require more run time and data collection to reset my brain from mildly massaged oem fuel economy to 160-170whp fuel economy. Haha.
Race 3 was a standing start, hottest time of the weekend and pace dropped a couple seconds for all of us. My DQ in race 2 put me at the back, which would have made for great video. It turned into a battle between just two of the three starters, as three others were missing from grid, including race 1's winner: Thai. Cagri and I had a couple lead swaps and he got by me after some really poorly timed traffic which added some mid race excitement. I was able to generate enough of a run through the esses(presumably due to his non-aero car vs my aero car)to get by him leading onto the back straight and set up a really defensive T17 hairpin onto the front straight, which sprung me free for the win. He was destroying me on the brakes into T17 all weekend as I was tip toeing around my brake cooling issues. Thankfully the GLocs played nicely, didn’t glaze yesterday and were amazing today in a mechanical-empathy situation.
I also did some setup consulting on the Tarmac 88 side for the another ST6 car before race 3. He won that race and said “it helped big time the tires held strong the whole race! It was so fun out there it was not an easy win that is for sure i kept having to fight for it but man did it pay off”
I miss a shift twice during lap 1 on the back straight, and fall to fourth. Fun game of catchup though with my setup changes after day 1's struggles.
Camera battery dies after I take the lead, but you don't miss anything other than my two ST5 lap record laps. Thai in my draft goes a tenth quicker second to last lap, so he gets that crown and the race win after I break minimum weight by ~2 gallons.
I miss a shift twice lap 1 back straight, fall to fourth. Fun game of catchup though with my setup changes after day 1's struggles.
Camera battery dies after I take the lead, but you don't miss anything other than my two ST5 lap record laps. Thai in my draft goes a tenth quicker second to last lap, so he gets that crown and the raec win after I break minimum weight by ~2 gallons.
I watched this video from the rear POV of the RX8, amazing racing and super tight group. I'm glad the podium had some great diversity.
When you weight in pre race do you not use a full tank? I've been starting to study the rules for TT/ST so I'm not really keen on how the whole process goes, but I want to understand them now so I can map out my TT/ST build
When you weight in pre race do you not use a full tank? I've been starting to study the rules for TT/ST so I'm not really keen on how the whole process goes, but I want to understand them now so I can map out my TT/ST build
Minimum Competition Weight is measured immediately post race, never pre. I was trying to ride the edge on my min weight to help close the .8 second gap to Thai. My new horsepower results in more fuel burn rate than i'm used to. Thats all.
Other rules related to comp weight are specific to TT/ST, but not how it is measured.
Gridlife GLTC was fun. Ran warm up, practice, qually and one practice race, but missed the practice race Friday night with a front hub swap, Points race #1 on Saturday afternoon with a new intermittent misfire and associated trip to town for parts. New plugs and a game of musical coilpack lead me to suspect the #3 coil was weak, so I called it a weekend and towed it home Saturday night. Pace-wise, I never matched my 1:37.9 from last august on a light-ish/158whp ST5 race lap. I was feeling really good with 8th in Practice until the top 10 all bolted on stickers for Qually. Saturday's rain played into my local knowledge though, and I was able to work from near the back up to finish 5th in Practice Race 2 that morning before the misfire issue popped up.
Also on Saturday, I put Tom O'Gorman in the car for a data lap. He put 3 tenths on my best lap, which is a moral victory for me. I had been feeling really rusty, but now I know I can just blame the 14 month old tires with 20 HCs. Anyways, here's some pictures...
Prep included spacing out my airdam so the splitter measured 3" instead of 4", pulling ~180lbs of ballast and finally moving the 225 R7s over to 9.5" wheels after I got my COVID delayed konig refill.
Hub swap #2 saturday morning. I killed both front hubs this weekend. One survived since Sonoma 2018, the other from even longer. I guess taking multiple 6+ month long breaks from racing helps stuff last a while...
Swappng to borrowed ~12HC tires for race 2 Saturday afternoon: I came in from the formation lap when the new plugs didn't solve my misfire.
how did you know the hubs went bad? noise? understeer?
One was found when the car simply went numb, with vague steering attributed to dynamic toe change on turn in. Budget Mercedes DAS.
The other was physical and audible growl when loaded in that direction.
Looks like I failed to talk about some of the front aero improvements.
So, looking at this photo, you can see a bunch of exposed front tire and the airdam meeting the bumper in a sort of curve:
I used some 1/8" aluminum angle and bolted in some 'bridges' to push the fender/bumper mounting location out. This worked wonderfully and covers the wider 225/9.5" setup really well. It also changed the angle at which the airdam meets the bumper, which keeps the airdam from bowing in. The airdam is now wider than my splitter, so there is even further optimization to be done with splitter #2, but this one has been rock solid since 2017 at this point and doesn't 'need' replaced. Alumalite FTW.
Front aero update #2 was the rad ducting.
Pictures explain this best. It's really simple. Coroplast, duct tape, and gorilla tape with a 5 zipties mounting it. It's shockingly sturdy since it essentially press-fits into the ledge between the radiator core and end tanks.
Square tube replacement from fellow MT.netters:
I left some of the OEM bar because my splitter cables mount there. I'll change that when/if splitter #2 happens this offseason.
I also left the little stamped mounting brackets for the top of the bumper. My rad duct uses those as well. Super handy.
Rough CAD template #1: This template is full width front to back, and purely 2D. Template #2 gained a bit if curve on the side pieces to narrow the inlet.
Transfer template from cardboard to coroplast:
(The lighter blue is the coroplast packing material the Supermiata Crossflow radiators ship with, AND it is the perfect core dimensions. So they're thoughtful enough to include 1/2 the radiator ducting with every radiator purchased)
Template #2 pictured here:
Old airdam laid over the new inlet duct:
Required changes marked before I trace the old dam onto a new 4x8 sheet of plastic:
Airdam #3: Wider, less inlet opening, way more front Df noted above in the race weekend recaps.
Not much happening this offseason. Excited to roll right into 2021 and just drive.
I would like to challenge the 1:35 range at Mid O and Gingerman, and log a sub 2:20 NCM,. To do that means entering TT4 alongside an ST5 race weekend. Plan would be to simply drop all 250lbs of ballast and potentially change tires for TT use.
S/TT4 Classing would look like:
2106lbs @ 180whp
The lightest I've been able to get the comp weight is ~2180 on 205/8" R7s.
So it shouldn't, and probably wont contest for records in 4, but i might sneak a regional win.
Last month I skinned the trunk, and I plan to attack the doors further. I also have a lawn mower battery from Turtle, since that buyer wanted an OEM one for street use. So maybe I can get down to 2150 comp weight?
Really weighing some further ST5 optimization vs multi-use convenience/economics.
At my 159 avg, 163peak ST5 power level:
- 11.75" TSE Wilwood DP4 bbk: Costs ~32lbs
- 4" splitter: Costs ~62lbs
Tomo just drove Marcus' GLTC 188whp/2380lb z3 car to a 2:13 with airdam/wing, no splitter. I'll be 15whp down, but 130lbs lighter @ 2250lbs in GLTC trim.
Really weighing some further ST5 optimization vs multi-use convenience/economics.
At my 159 avg, 163peak ST5 power level:
- 11.75" TSE Wilwood DP4 bbk: Costs ~32lbs
- 4" splitter: Costs ~62lbs
Tomo just drove Marcus' GLTC 188whp/2380lb z3 car to a 2:13 with airdam/wing, no splitter. I'll be 15whp down, but 130lbs lighter @ 2250lbs in GLTC trim.
Yeah I don't think the protruding splitter is worth the ~62lbs at that power:weight. We gotta live with the BBK hit though, IMO.
Another bit on the GLTC lap-times at NCM, TomO drove 2 Caymans, both in the 2:15s the same day he did 2:13s in Kmiatas(including mine). So a lighter extremely good handling car can get is done! I guess we aren't surprised though?
07-27-2020, 10:14 PM
3
