Honda K24 Swapped 2015 BRZ Ship of Thesus (NASA TT5)

[RedReplicant]

Originally Posted by autoracer86

great stuff as always and yeah your overlay seems slow, One thing I noticed is your G meter like mine seems "inverted".

Like I think the G meter ball should go the opposite way of the car movement in turns.

Hah, I didn't even notice that before. I wonder if it is related to running the camera in 60fps mode, I'll see if there is less delay on 30fps.

Originally Posted by Pat

Helluva season, and so much more to go. Congrats on the success. I'm interested to see what you come up with for a tranny cooler. I was told to do it "right" it would be several thousand dollars.

Thank you

It does seem like there is no good dirt cheap way to do it right. $800-ish minimum using a Setrab fan/cooler pack, Genesis pump, thermostat, and lines. We will see, I'm not really sure where I want to mount everything too, I'd rather it be in the right rear of the car for weight distribution.

[redlined600]

Nice work! Hopefully the success makes up for the troubles!

[redlined600]

Nice work! Hopefully the success makes up for the troubles!

[redlined600]

Originally Posted by RedReplicant

After a weekend with the SC3 Corsa I like it a lot - the video quality is very much improved. It's also super nice to be able to download the videos off the camera, add them in RS3, and have all of the data alongside the video and broken into individual laps to compare.

Good to hear! The smarty cam 3 sport is so tempting for those reasons. I think I just need to pull the trigger at some point.

Originally Posted by RedReplicant

The new overlays are nice, but I feel like the G-plot updates slower than on the SC2 and the delta / delta to fastest lap need some work since it resets every session and doesn't start until the second full lap, which is pretty damn annoying.

I thought there was an option in RS3 to select a static lap, I seem to remember reading about it recently.

Originally Posted by RedReplicant

I also ended up getting a CanChecked MCE18 so I can add a few more inputs to the Haltech. You wire the thing to the Haltech CAN network and it emulates a Haltech IO Expander. ProWire AMP SuperSeal solid pins are super nice to work with compared to the annoying crimp style pins too. First thing I added was a fuel pressure / fuel temp sensor, next I'm going to be adding a transmission temperature sensor and very likely a transmission cooler.

Oh man, this is super cool. While I think the chance of me having enough patience to get it working is approaching zero...I might need to try it anyway.

[949 Racing]

Originally Posted by RedReplicant

The car seems overly tire and setup sensitive to me, so I'm making a couple of changes to try and help that. I feel like I've been a day or two behind in realizing what is going on with the car setup wise for whatever reason, ideally I wouldn't have to screw with it at all and I'd just drive the car.

Currently on 500/600 springs, 22mm Perrin front bar on full soft and Mann Engineering 13mm rear on full stiff. After doing a bit of thinking I'm going to 450lb springs up front and a Karcepts rear bar.

Karcepts doesn't list that he sells a rear bar yet, but he sent me this:

I'd bump to the OEM or GR rear bar before dropping front spring rate. Going lower in front only increases the risk of blowing through the travel and spending too much time on the stops. The same problem you had with your out of the box set up. That would actually increase understeer. Unless you are too low in front or not running enough camber, you should have plenty of front grip with your current set up. You above 130mm front and at least -5°?

Regarding sensitivity to set up, you are right in that higher spring rates, all else equal, make the set up more sensitive. Higher rates also make the car more sensitive to driver inputs. So smoother, slower inputs are required to extract the extra speed potential. Sway bars are springs too so adding more bar has the same downsides of more spring; additional sensitivity to set up and driver input. Agreed though, when we wen to 616/616 (11kg) rates on Blub, it was definitely a tad harder to drive than 500/500, but also quicker.

Let us know what ends up working for you.

[RedReplicant]

Originally Posted by 949 Racing

I'd bump to the OEM or GR rear bar before dropping front spring rate. Going lower in front only increases the risk of blowing through the travel and spending too much time on the stops. The same problem you had with your out of the box set up. That would actually increase understeer. Unless you are too low in front or not running enough camber, you should have plenty of front grip with your current set up. You above 130mm front and at least -5°?

Regarding sensitivity to set up, you are right in that higher spring rates, all else equal, make the set up more sensitive. Higher rates also make the car more sensitive to driver inputs. So smoother, slower inputs are required to extract the extra speed potential. Sway bars are springs too so adding more bar has the same downsides of more spring; additional sensitivity to set up and driver input. Agreed though, when we wen to 616/616 (11kg) rates on Blub, it was definitely a tad harder to drive than 500/500, but also quicker.

Let us know what ends up working for you.

I'll give swapping bars before springs a try - I've got the Karcepts rear on the car, a 14mm OEM, and a 15mm OEM here to play with now. Blowing through the travel was my worry with going down to 450lb up front for sure. The idea I had in my head is that dropping to 450 would move the overall balance enough that I could run the rear bar in the middle and then adjust from there, but that could have been misguided.

By setup/tire dependent I mean that the car can go from right on balance wise to too tight depending on the track and tire heat cycles.

For example, at Arizona Motorsports Park on sticker RC1s the balance was pretty good. When I went to Podium Club with 5HC on the tires and an incredibly rubbered / abrasive surface the car was tight mid corner, which cascaded to the expected higher front tire temps and accelerated wear.

I ended up going out and measuring everything this afternoon.



Current relevant parts:
500/600 Rates w/ Roll Center Correction
22mm Perrin front full soft / Karcepts rear, prior was a Mann on full stiff
17x9.5 +40, 5mm spacer up front to keep the tire out of the dust boot
OSGiken Diff

I can add the rest of the front camber plate (it is one hash mark on the plate), the rear I need to find a thin jamb nut for and it'll give me -3.3*.

[RedReplicant]

Talked to a few other friends that were at Podium Club that day and they all reported the same thing - cars felt great at Arizona Motorsports Park a few weeks earlier then lots of understeer at Podium Club. Track was really just overly hooked up.

I signed up for a Porsche Club event for 12/2 at Podium Club - leaving the springs at 500/600 and bringing all three rear bars with me.

[949 Racing]

Everything else being equal, adding grip will tighten a car up a bit. Once we get a car setup working for a particular tire, we tend to just raise or lower the rear to fine tune mid corner balance. Front is typically as low as we can go without bottoming so adjusting rake is our preferred trackside tweak for different tracks or weather conditions.



Pyro readings good?

[Kelse92]

Originally Posted by RedReplicant

Talked to a few other friends that were at Podium Club that day and they all reported the same thing - cars felt great at Arizona Motorsports Park a few weeks earlier then lots of understeer at Podium Club. Track was really just overly hooked up.

Podium Club is a fairly new track/surface right?

This seems to be common on newer surfaces for the cars to be pretty understeer-prone on new surfaces and then ease up over time, we experienced similar here when Eagles Canyon was repaved. Just adjusted setup accordingly per each track.

[RedReplicant]

Yesterday went pretty smoothly other than some dumb first session PCA shenanigans involving me, a Cayman GT4, and a Cayman GT4 Clubsport.

First session was a waste since the Clubsport refused to point me by, but it let me know the Karcepts bar I'd put on full stiff wasn't enough so I slapped in the OEM 2017+ 15mm bar I brought with me and that helped a lot. Played with the knobs a bit and I was pretty happy with the balance for the grip at Podium Club while somehow experiencing zero EPS cutout.

I was able to get a handful of rolling lap matches to my PB in the last session of the day on a set of almost corded RC1s. I was playing it pretty safe all day, especially through the uphill after the esses and the following left hand downhill sweeper, since there was nothing to win.



I had AIM issues, so this is the quickest complete lap from session 3. A pretty casual 1:42:18. I'm pretty happy with that since I left a bunch of time on the table being safe in a few spots and the difference a set of stickers makes over 22HC ones. This is half a second off my PB.

Originally Posted by Kelse92

Podium Club is a fairly new track/surface right?

This seems to be common on newer surfaces for the cars to be pretty understeer-prone on new surfaces and then ease up over time, we experienced similar here when Eagles Canyon was repaved. Just adjusted setup accordingly per each track.

It is, yeah. Lessons learned

Originally Posted by 949 Racing

Everything else being equal, adding grip will tighten a car up a bit. Once we get a car setup working for a particular tire, we tend to just raise or lower the rear to fine tune mid corner balance. Front is typically as low as we can go without bottoming so adjusting rake is our preferred trackside tweak for different tracks or weather conditions.



Pyro readings good?

This is actually where I had some questions. Based on my pyrometer readings and off track temps it seems like the RC1 needs to be run around 38psi hot. I dunno if you ever ran them on Blub, it just seems high to me but I guess the answer is simply to be a slave to the numbers?

Also, there is a roughly 10-15f delta between the hotter front temps versus rear. Is that about normal, or do you try and get them to be pretty much within 5 degrees or something.

I'm slowly coming to terms with the idea that the car doesn't need to have any drama to be fast, if that makes any sense. It is just smooth and ridiculously easy to drive.

[949 Racing]

Most radials are fastest when inside temps on loaded side (left tires on clockwise track) are 15-20 hotter than shoulder with a fairly even gradient across tread. Inside tires will be cooler. Some course heat fronts more than rear, other courses are the opposite. More than F to R temps I simply look for balance. When its really easy to get the nose pointed down to the apex with only gentle trail braking and allowing early power application without power oversteer. And yeah, when it's dialed, its very easy to drive fast. You'll find that your fastest laps are the ones with the least steering input and corrections. Basically steering with the pedals. Bit of trail brake on entry, full power early without lots of steering lock to get the job done.

Regarding RC1 pressure, yes slave to the pyro numbers. Be willing to experiment but the pyro will get you in the right neighborhood.

Our pyrometer FAQ

.

[RedReplicant]

Last NASA event of the year went pretty smoothly, didn't drive real well and corded my other set of RC1s but I pipped the 5 record by .030s for a win. Got to play with my collection of rear bars too.





1:47:717 on official timing

We don't know what NASA is going to do rule change wise for 2024, so I'm kinda frozen at this point.

I ended up doing the math on my new motor dyno from a couple of months ago and got 199whp. This so happens to be the exact number to run a 1.0 tire with zero changes to the car... I'm mostly considering this because I'm out of tires, Maxxis is currently backordered on the RC1, and I need a set of something in the next three weeks for the first events of the 2024 season. RE71RS or CR-S, we will see.

I intend to go get destroyed at Utah NASA nationals in August.

[DocWalt]

Going to consider the new Toyos too?


I'd do the CR-S before the RE-71RS for your use, I think.

[gt5759]

Originally Posted by DocWalt

Going to consider the new Toyos too?


I'd do the CR-S before the RE-71RS for your use, I think.

Curious as to your reasoning on that?

I found the CR-S to not have the same lateral grip as the RE-71S. The CR I felt put the power down better oddly enough. They both ran pretty much the same times for me. The RE also had more grip first out the gate, CR needed some heat to come on. Just my worthless two cents on any of this. Also, the Yoko A052 was faster for me than either of those, but I am not a tester and did not do all of this on the same day.