X25

You could probably lower the whole mount height with what Bruno just referenced. In my case, the height was good, and I just needed to shift it a bit. The gap I still had was an uneven gap, so there's no easy fix to eat, and I just sealed it : )

Yeah, overall the hood looks great! I am also looking forward to trying it out this weekend : ) Besides better cooling, it should also let the splitter do its work better.

I suspected as much, but I did not see anything accessible without removing stuff. if my spacers did not work, I'd indeed have to do it this way. The good things is it will be perfectly aligned when I switch back to OEM hood : )
Thanks for sharing!

djnice

Thanks so much, but I will have to take a rain check. Too much going on in May. Hope Area 27 will be an option again later this summer.

X25

Getting ready for the trip, I've decided to come up with a simple cover for the louver opening, so the rain and dirt would drain by the opening behind radiator instead of the throttle body, etc. during the road trip.



I can put this on or off within a minute.


Covers most of the rear openings...


The single front louver is left open.


I ordered two new Apex wheels (18x11 ET38, front) last week, and they are getting A7 tires mounted along with TIRELIEF right now as my spare front set for the trip.

• I kept the fresh set of A7s (315/30/18, 345/35/18) on the car.
• However, in case I prematurely wear out the fronts for one reason or another, I will have a spare set of fronts with me that I can quickly switch onto.
• I am also testing a new balancing method for these new wheels:
  • The race shop will first balance the wheel with TPMS and TIRELIEF, but with NO TIRES.
  • Once balanced, they will tape over those weights, mount the tire, and will then balance again.
  • This way, if the tire spins on the wheel, I will simply remove the wheel weights that were added along with the tire, and will still have a fairly balanced wheel, preserving my hubs, brakes, and suspension parts' life.

X25

Well, I finished my long weekend trip. I have not broken any (self) records, etc., but it was quite ADVENTUROUS nonetheless.

For the reading inhibited, you can skip to pics

• Everything was good as I arrived at ORP for camping, and I very much enjoyed camping in the new truck, with HVAC keeping me at the right temp. I got to watch a few shows, also employing the awesome sound system of the truck as well. With the rear seats folded, the new truck provides flat bottom service, giving me ample space to get comfortable. I also had ample power of course, which is the main reason why I bought a hybrid truck : )
• The next day at the track, I wanted to test if A7s would hold up during a whole day of track driving, and I started with a brand new set to test it out. The answer is NO! : ) I literally burned money, and corded the front tires after just a few sessions...
• In the evening, I detached the truck from the trailer, and went down to Biggs Junction to get something to eat. The truck suddenly started OVERHEATING. I had nowhere to pull over for a while, and when I did, the truck's coolant temp was at 254 degrees F!! It's a 21 PSI system, similar to Corvette, so I had perhaps 10 more degrees F before things would start blowing up. I checked, and realized coolant level was below MIN, yet I did not smell any burning coolant.
• I filled up the coolant reservoir with whatever water I could find in the truck and went back to my camping site. Around midnight, got out to brush my teeth, and wanted to check the level, it was at MIN! There was also a small puddle in the middle of the truck. Later, I learned that there is a heat exchanger that scavenges exhaust heat during hybrid/EV driving, which is exactly the mode I've been staying during my camping!
• I realized I can't stay camping in the truck, and decided to top it off and head home at midnight. I've used the longer Portland route to make sure I'd have reception if I got stranded.
• I set the truck to tow/haul mode on my way back, which disables electric-only mode, thinking it would reduce coolant consumption. Indeed, the coolant level was still at max after 7 hours of red eye driving with 2 redbull cans.
• I slept at home for 8 hours, and after breakfast, headed to Canada for the second event at Area27 in Oliver, BC.
• Right as I started getting the hang of the track again after a hiatus, right as I was shifting from 2nd to 3rd gear at WOT, the engine drastically cut power, and displayed "Engine power reduced". This was actually pretty scary, and I'm somewhat glad it happened at the straightway.
• The code was P0102; MAF voltage low. Of course, noone has a MAF cleaner spray with them at the track, so I tried to clean it anyway by spraying water and then blowing hard on it (don't do it!!). It did not work, concluding the day pretty early. I immediately ordered a replacement MAF on Amazon, to be delivered the next day.
• The new MAF did not work. I still got the same messages. Found out that the harness for the sensor right next to MAF was drenched in oil, and could have caused this issue. Thoroughly cleanred it with connector cleaner, but the codes did not clear up.
• I highly suspected harness/wiring not working, since the car was setting the code even when I turned the engine on without cranking the engine (i.e. MAF measuring nothing still threw code).
• Finally, I decided to go through all 116 fuses this car has before giving up on it and delegating to a shop. Guess what, F77: OFF ENG COMP was BAD! I replaced it, and SUCCESS, everything works again!!!!! I still think the harness right next to MAF, drenched in oil caused the short circuit, blowing this seemingly unrelated fuse, but it's hard to know at this point.

With the windows covered by screen, it provided a cosy camping experience, while still keeping inside warm, and powered, running the engine only for a minute every 20 minutes.


It was pretty roomy inside to camp with the rear seats folded, and I very much appreciated the flat floor, letting me have good sleeping surface for the mattress, and ample headroom.


MAF sensor was $63 shipped, but did not solve my P0102 issue.


The connector next to the MAF connector, coming from the same harness, was completely drenched in oil. I used an electric connector cleaner, which very quickly de-greased and cleaned both sides of the connector.


The long list of pending error codes, and the P0102, proudly showing itself on the top.


Going through ALL the fuses, F77 was the only bad one. And when replaced, problem was fixed. I still believe the root cause was the oil drenched connector, that probably caused a short circuit.


During my inspection, also replaced my air filter. I initially feared it might have been soaked in water due to bigger opening from the LG hood's gap, but it was not the case.



I'm very very happy to have solved this problem, or else I'd quickly run out of choices, and would likely have to go to a dealer. I have also dropped off the F150 truck, and told them which part is likely leaking; hopefully they can fix it soon, too. If they do by Saturday, I plan to attend a track day to test out the car at Ridge Motorsports Park.

Citation

That fuse did not blow for no reason. You'll want to pursue the cause or risk having that upset happen again.

X25

I'm hoping it was the connector right next to it drenched in oil. That said, my race shop tech said oil does not cause short circuits, and that it might be something else. I've thoroughly cleaned up both connectors either way.

I'm also wondering if it could have anything to do with the new battery I use (MegaLiFe). If it happens again, I plan to switch back to the pig-heavy AGM AcDelco battery and see if it helps. Either way, ordered spare fuses yesterday, just in case you're right (but I hope not) : )

96GS#007

I'd be surprised if the battery caused the fuse to blow. Seems like it'd take more than one out if that was the case. When the opportunity presents itself, I'd follow the harness as far as possible and see if there is evidence of it being pinched. Electrical problems suck!

X25

Well, I went out for a quick test drive, and it blew that fuse again. I switched back to the AGM battery as well just in case, and same result.

I removed the tape around the harness all the way until the junction with injector harness, and there is no sign of pinch or damage. I even tried again with the harness cables uncompressed, and blew another 15A fuse right away (same location of course; F77).

At this point, I'll just suck it up and bring it to the dealer. I'm starting to guess that the controller module might be damaged. It was one of the steps listed in official troubleshooting doc in this thread. I still have powertrain warranty left, but we'll see what happens to that with the race seats and front splitter (which I'm a bit lazy to remove). Hmm, thinking of it, the seat plugs are exposed under the race seat, but well I guess they'd not cause MAF failure : p

X25

I just picked the car from service, and it turned out to be passenger side O2 sensor! It apparently short circuited with the insulation, and blew F77 fuse, which in turn caused MAF P0102 error, and everything else. The dealer said emissions is not covered under powertrain, and charged $578 ($63 of which is the new O2 sensor). Anyway, I'm very happy to have the car back and running with no issues : )

BrunoTheMellow

yeah only 2 years warranty for o2 sensors

X25

After checking things out, I figured out that the whole issue was very likely caused by the dealer when they replaced the cats under warranty. I don't remember how the wiring looks from the factory, but on both sides, the O2 connector was pretty close to the cats and even the side that has not yet failed started to melt down as well. Oh well, nothing I can prove, but it's a lesson re-learned again that we should always go through what dealers do to make sure everything is in good shape.



Re-taped the whole wiring now that we know there was no issue with it. The dealer left it as is (which I guess makes sense). Anyway, it's taped better than ever now : )


The angle is measured including the gurney flap, which increases it by 4 degrees. As such, the wing used to be at 10.4 - 4 = 6.4 degrees. I moved it to max I can without having to modify the mounting base, which is 15.5 - 4 = 11.4 degrees.



As you can see from these graphs (of lab tests), 10 degrees AOA is pretty much the sweet spot for this wing at gains vs drag, and down force doesn't increase as much when you move to 14 degrees. I also do have larger side plates (better use of wing's ends) and gurney flap (increases effective chord length, increasing downforce all over the graph while not adding much drag).


Side plates need to stay parallel to the ground to work efficiently. The adjustability is not as much as I'd like, but it works.


Moving on to the O2 sensors, the wiring of the sensors is pretty close to the cats.


This is the driver side (that has not yet failed), and you can easily see some heat damage on it. I don't remember how they were laid from factory, but they are definitely too close after the cats were replaced by the dealer.



Unplugged the wiring, and inserted a DEI heat shielding sleeve over it. This should hopefully put an end to this issue. Also used metal zip ties to tuck them away a bit.


Finally, also moved the front sway bar to the softer setting. I don't have the rear jumping on me in hard turns as well as long corners, and as such, I think softening up the front to allow more front bite would help. The rear wing will also put more downforce at the rear, so I think this would be the best. We'll see : )


Now, if only my F150 can be fixed (it's leaking coolant from the heat scavenging loop on the exhaust), so I can attend more events : ) I asked the dealer to consider welding the leak shot to temporarily fix it, while we wait for the part, and will call tomorrow to see if they followed my advice : )

Oh and finally, I checked my transmission fluid level, and it's still at fill plug level after making so much mess with the slow leak. Instead of replacing the fluid fearing it might be getting low, I decided to leave it as is.

emperors61

Thanks for keeping us updated, very interesting failure modes. What transmission fluid temperature did you run to check the fluid level? I have the automatic 8L90 and whenever I use the temperature set by GM (35–45°C (95–113°F)) to check the fluid level it pukes at the track. I thinking of using 131F-149F based on: "CTS-V/LT1 Camaro, if running a track session, should have the transmission fluid level checked when the TFT is between 55- 65°C (131–149°F)."

village idiot

I'd be super interested to see lap times and data (entry/exit speeds) between the angles of attack!

X25

I don't know of a desired temp range for checking on the manual transmission's level. In this case, I was about to change the fluid, and the car was cold (65 degrees F ambient), before I decided to cancel changing it.

If anyone knows better, please chime in : )

Me, too! I should get some good comparison data at ORP. I think max I reach there is about 125 MPH.

RMP has recently added a chicane to their straightway, I will likely not get to compare what happens to the corner before which I used to reach 145-150 MPH, unless that chicane is skipped during some of the events.

village idiot

How long is your splitter and what size tires are you running? if it's the 305/325 scrubs, I wager 25 internet points it' somewhere between insignificant difference and faster at 0 AoA than 10.

Obviously, bigger rear tires and longer straights favor less AoA.

X25

It's decent in size, and is also tunneled:
https://www.lgmotorsports.com/lg-car...-splitter.html



Center


By the cheek coolers


I usually use 315/30/18, 345/35/18 Hoosiers (usually R7), or 315/30/18, 345/30/19 Toyo RRs.

I would love to try my best with different AoA and record lap data on the same day; switching wing angles is pretty simple. I had to deal with so many issues since I got the wing on (transmission popping from third gear, fixed; MAF engine power reduced error, fixed; scraping the splitter too much, fixed with coilovers; cooling issues after splitter install, hopefully fixed after LG hood) that I could not really focus much on figuring out what works best.


EDIT:
Back in the day when I owned the Z51, most of the transmission leak was solved by attaching a little pipe to the breather, even though it was not good enough to really seal the breather. I'm guessing the additional push down of the hose was making the breather open less easy, which might have helped.


Following that idea, I've attached a 1/2" ID hose onto the breather, and made the hose kink a bit by the wall. The hose would obviously flex if the transmission moves, and this might indeed help me with this leak issue, just like it did when I owned the Z51.


While at it, I also used engine degreaser to clean up the transmission to see how it fares in next events. Well, it worked pretty well; it's never looked this clean for years : )

village idiot

It's definitely a nice piece of carbon and a pretty good length! Did they give you any rough idea of downforce it creates?

Just "wild guessing" with a little bit of (old) experience, I bet that thing probably makes about as much as your wing will at 10 degrees and maybe a touch more. Depending on the rest of the car's balance, alignment, tire sizes, etc, that's pretty good!.

Have you run it? Is it pretty noticeable?

X25

I really need to focus to figure out how the aero changes impact handling, but kept having issues since I got them on.

• The splitter seals the bottom of the car aft the radiator, and it turns out C7 cars dump most of their radiator air to the bottom of the car. This caused the car to run pretty hot (but not overheating). I upgraded to the 70mm DeWitts radiator and also installed the LG hood. The temps were all good during my last run, so hopefully this issue is addressed.
• The splitter was also scraping the surface in quite a few places at the track, despite the car running very close to stock height. The inside of the carbon-fiber piece, unlike OEM, is filled with a not-so-strong filling material. As such, it cannot withstand the abuse as much as the OEM bits would. I installed Ti scrapers and also switched to tractive coilovers. The coilovers by themselves pretty much fixed the issue. I also put a perimeter sleeve to protect the edges from opening up.
• While working on these (or was it before?), I also had issue with 3rd gear popping to neutral. After warranty work being done (that replaced third and 4th gear synchros, etc.), the issue remained. I fixed it by moving the whole shifter assembly backwards by what the mounting bolts allowed (3mm).
• Battery died, and reviving it when the battery is still connected meant the relays clicking on and off a lot for a few minutes, and after that, DSC controller stopped responding. It cost 2 weeks turnaround time with DSC, and still not sure if it was caused by low battery voltage, or something else.
• Finally, the O2 sensor wire was apparently touching the cat, and it short-circuited, blowing a fuse and forcing the car into reduced power mode, last time I was at the track. All the wiring is now secure.

In short, I really didn't have time to concentrate on impact of aero changes, but definitely plan to do so. I also ordered a set of RRs as the second set. RRs last a lot longer than other tires I use, and though a bit slower, they're relatively consistent, so I would not have to focus on tire wear as well during my tests; at least that's the plan. Besides these, I'm also not a pro, and aero changes often require bigger ***** (or a bigger bank account) to exploit them fully. We'll see how that goes : )

village idiot

Here's what I remember from my motorsports imagineering days: Splitter getting too low (and touching!) is a very dangerous thing.

That's a serious splitter that's creating real downforce. You're going fast into turns with that car, slicks, etc. If it blocks airflow on the brakes (when you are really using the front grip), you just cut off a lot of front downforce, quickly, and bad things can happen. Going from 300lbs to DF to 0 can definitely be the difference between getting through a turn with margin to, well, not.

With regard to fortitude, you'll just get used to grip and adapt. I didn't even realize it, but I was adapting to my BRZ being heavy understeer in fast turns and neutral in slow turns (wing overpowers splitter with speed).

olblue75

How do the side plates affect down force? Or is it more of a side to side force keeping the car more stable left to right wise?