izanami

So I recently did my 2nd HPDE weekend at the motorsport ranch in Cresson and figured I would share some of my lessons learned. First of all, if you don't already, do track days. They are awesome. My car is a 93 R1. It makes low 300s at the wheels on stock twins, has Ohlins, stock sway bars, and all the reliability bits. Tires are Dunlop star spec II, 285 rear and 255 front.

Catch can is a must. I only had a vent to my primary turbo inlet. After my first event in March, I had oil EVERYWHERE. The intake tract was literally dripping after i pulled pipes off. In front of the BOV had oil sprayed all over, including seeping through the hood seem, and down the side of my headlights. I was convinced i had a turbo dying. I put in a vented catch can, and all is good. I haven't looked how much is in there, but there is nothing coming out the BOV anymore.

Brakes. Im using stock brakes with EBC red pads. They feel fine mostly, but they did start fade a bit as my speed piked up. What worries me though is that they look like they are actually crumbling, so I will probably replace them before next track event. Also, I don't think this track is very hard on brakes. Especially since there was water flowing over the track just before the 2 hardest braking areas. I hear Carbotechs are good pads for the track, so I will probably put a set on at the least. I think a BBK will be necessary if either I get much faster, or go to a more punishing track.

Cooling. I have a Blitz FMIC with a Koyo behind it and no AC condenser at the moment. Stock oil cooler with a lot of smashed fins (will straighten soon). It was high 80s during the day and super humid. Water temps got up to 106C on the PFC. slight lower indicated in the throttle body coolant line. 110C was the hottest I saw oil temps in the pan. My understanding is that isn't danger zone, but kind of tosty. I want to put my AC back in, but I don't know how much affect it will have on temps. I could work on the ducting around the radiator, but im not sure how much I have to gain. What would be the biggest boost to cooling capacity? bigger oil coolers, front bumper, vented hood, something else? I know a Vmount is a better option, but its a big change.

Tires. I set my cold pressures to 30 front and 28 rear. At the end of the run (minutes after) fronts were about 35, outside rear was about 34, and inside rear about 31. Should I be setting cold pressures for an even hot temp or what? if so, whats a good hot temp to shoot for?

In some places, the rear felt a little twitchy, especially in the high speed corners. I was considering disconnecting my rear sway bar for the next event. Does anyone have any experience with that? I know most people recommend a lower spring rate in the rear, but I don't want to make big changes yet without a little more track experience. I haven't done anything to measure travel, just going by seat of the pants feel.

Obligatory video is below...

Mrmatt3465

iTrader: (10)

I recently had cooling issues at my previous event, however I don't haves FMIC. The biggest thing I did to help was make sure you seal off the radiator really well. When I installed my Koyo, I added foam to the sides but didn't realize I had a large gap between the undertray and the radiator. I have since dropped the undertray and added foam to the lower half of the radiator, and even where the power steering cooler and AC condenser lines pass through. I also drained and filled my coolant last weekend with a 70/30 water/ethelyne glycol mix with a half bottle of water wetter. I have already noticed a 5-10*F difference in normal cruising temps in the hot Arizona heat (100*F+ everyday). On your oil coolers, there are rubber flaps on the top of the ducts that deteriorate with time. If they are falling off or missing, then a lot of air will bypass the oil coolers. Check those for serviceability.

Matt

Johnny Kommavongsa

iTrader: (13)

Cool thxs for sharing. I recently did my first track event and had a blast.

Dont really have any tips on cooling for you but from what i read the shark tooth mod which open up the front bumper would probably help.

I know vmount is major change but i feel like thats what the majority of people are going to say.

Sucks that the blitz FMIC and koyo isnt cutting it. I also have this setup but my koyo is dual pass radiator. I have a touring but running a rx8 oil cooler on the passenger side. Both coolers are duct.

How much was the system you used with your video, it looks pretty cool. Was it easy to setup and record?

HadaVette

iTrader: (3)

I've also tracked my 93 a few times, and autocrossed a lot. Track tires have been 245/45 and 275/40 17's, pretty similar to yours (255/35 and 285/30-18's for autocross). I have Ohlins as well, which I really like, and a larger adjustable front bar. I really liked the handling when I disconnected the rear bar. Nice and stable. How's your alignment? I run a tiny bit of toe in in the rear.

The oily mess and catch can story sounds familiar! LOL - what a mess. I'm running my can 'closed loop' if you will, with the venting going back into the front turbo. It filled up each session last time out, seems like a lot of oil. I think I'm still chasing the best answer there...

SakeBomb sells a nice dual oil cooler kit, which is in my car. I still need to work on ducting, but the kit is top notch. I think it's the next step after a good radiator.

Sounds like you had a great time - Awesome!

Smokey The Talon

iTrader: (33)

Dual oil coolers and proper ducting are a must for extended tracking. I would try to keep the car below 105C water temps and I even try to stay below 100C.

Tune your tires for hot pressures for now. Getting tire temps with a pyrometers is the best but not needed until you get more serious.

I've done an abbreviated shark tooth mod I call the Bubba Gump where I take the middle existing bolt hole on the lower bumper and drill a hole in the under panel right below it then use a bolt/nut to cinch it down and open the bumper opening a bit more that way.

izanami

Thanks all for the input. I guess I'll put some effort into ducting when i start picking at the oil cooler fins I think the bottom of the radiator is sealed up pretty good, but there is a good bit of space around the sides. I have seen the sakebomb oil coolers, and they look sweet. Just wasn't sure how much they would help over the dual r1s unless I had some bigger air inlets to feed them. My first track event was in march and it was like 40F, so engine temps were a non issue. On the street everything stays around 90C so its hard to know if I'm helping things until I push it. Without AC, I don't drive it to much when its 100+...

Im running 0 toe rear and 1/16 toe in front. Camber is -1.2 all around.

Video is taken with "Harry's lap timer" app and a gopro. The app is pretty nice, it will record on a phone so its self contained also. It takes a little playing with to get setup how you want, but its way cheaper than a dedicated system. Also it will show live position on track and times of other drivers using it.

Also, I forgot to mention tow hooks. I dont have any. They let me run without them, but strongly recommended finding something if I kept tracking the car. It was super wet off track that day so there was a good chance of getting stuck if you went off. I ended up ordering a set of feed hooks ($!). I don't have them yet, but they look like they will fit around the Blitz FMIC. The cheaper e-bay ones that go to the stock tie down hook would be blocked.

ThunderSprinter

I like to trim bumpstops to finely tune handling balance. Got the idea from circle track guys. Basically when the bumpstop engages the effective spring rate goes up dramatically and can cause loss of grip. If you have too much oversteer, trim the rear bumpstop a little. It will give you less effective spring rate and reduce oversteer. Of course this assumes you are coming onto the bumpstops on hard cornering which in my experience most cars (especially low ones) do. You can test this with a zip tie on the shock shaft. To get back the spring rate just go get some plastic spacers from home depot and slot them to go over the shock shaft, thereby spacing the stop back down.

BLUE TII

iTrader: (9)

Tires are Dunlop star spec II, 285 rear and 255 front

In some places, the rear felt a little twitchy, especially in the high speed corners. I was considering disconnecting my rear sway bar for the next event. Does anyone have any experience with that? I know most people recommend a lower spring rate in the rear, but I don't want to make big changes yet without a little more track experience. I haven't done anything to measure travel, just going by seat of the pants feel.

Just my opinion, feel free to consider it, ignore it, file it away for when you are ready for it.

You aren't going to learn to drive correctly with the stagger set-up or disconnecting the sway bar etc. You will keep your bad habits.

The rear end is "twitchy" because of your inputs are incorrect.

The stagger is masking the problem and making it worse because the extra rear grip lets to make your mistakes and get away with it most the time until the forces build up enough to overcome the false cushion of grip from stagger and step the rear out.

Specifically, anytime you are on or off the throttle in a rwd car you have to change your steering angle to compensate. In the video you are trying to hold a driving line and holding a fixed steering wheel position while varying the throttle- that does not work.

In a rwd car if you hold the steering wheel fixed and vary the throttle you are requesting the car to change driving line.

Anytime you want to get on or off the throttle and want to maintain a driving line you have to unwind the steering wheel simultaneously or even in anticipation to maintain the driving line while managing the tire loading.

A balanced, neutral handling RWD is only neutral handling with neutral throttle- you control that throttle, you control the balance.

Best way to practice this is in a car that has a tendency to oversteer, in a safe environment, at lower speeds.

I recommend swapping your wheels/tires front to back and going to autocross.

izanami

When i bought the wheels I actually ordered a square setup originally. But they didn't have all 4, so i changed the rears because I'm impatient. No way the rears will fit on the front though (10in RPF1s). I still have the stock wheels but the tires are rock hard. I may put some new rubber on and take them out next time I go. I have autocrossed a couple times a few years back. It's fun and helped a lot, but its at least a full day of time and work for not a lot of time behind the wheel. I think the 2 day HPDE with a good instructor may be better bang for your buck (or hour).

I hear what your saying about holding the line instead of unwinding on track out though. I actually spun exiting the last corner the lap after the video above because of that... I was getting better about it toward the later sessions though. There is a wide double apex corner before a long straight that the instructors say to try and hold a constant steering angle and control the line with the throttle until the last apex.

ArmenMAxx

iTrader: (21)

When a car is as balanced as the FD, the smallest inputs can be enough to create dynamic changes in the chassis. Usually over-rotation. This can be a good thing if you apply it correctly on the correct turns and know how to steer with both steering and throttle inputs. Its what makes the car fun, but you have to be smooth.

Edit: Hard to tell from just a vid, but could be your dampening in the rear is way to soft. It could make things twitchy at higher speeds. Obviously check tire pressure also.

Cooling:
Seeing 90c in normal driving is suspicious. Are your fans coming on around 85c? If not, adjust with your PFC/Datalogger. 90/10 water/coolant helps a lot. I just started running 100% water with 1 bottle redline water wetter. Tired thermostats can also contribute by not opening all the way, even before they "fail". I change mine every 3ish years. My cruising temps around town are literally 81-83c on hot or cold days. Canyons driving it never goes above 86c. Track days, if its less than 90degreesf temps don't hit 90c.

izanami

I guess I should clarify, I see 90c MAX during normal driving. Usually thats stopped in traffic or light to light in hot weather. if I'm actually cruising down the highway it's 86-87. I thought thats where the thermostat opened. Even highway driving below freezing i don't think i would see 81. No canyons to carve in north texas, so cant relate that one unfortunately.

I have been running about 70/30 water mix by my finely calibrated eye. I thought I remember reading something about water wetter promoting electrolysis and pitting between dissimilar metals or something like that. I guess enough people have been running it without issue, so probably just a random internet falsehood.

ZDan

I'm using Carbotech XP10 as my street and track pads on the FD at the moment. Never had any issues with them. I do have bigger brakes, but also more horsepowers (pushing 500 at the wheels). They don't eat up rotors, are good for at least four 2-day events for me, and are quite streetable

I aim for 38psi hot all around. I usually start at ~32/30 and bleed down to 38 hot after lapping. You might start a little higher so that you end up ~38.

I've disconnected and reconnected my stock '94 rear bar a number of times depending on the track and how the car is handling. On my car, doesn't make a huge difference to the balance. I have Ohlins with 13k/11k springs and a Speedway front bar set to the middle of 5 settings fwiw.

Feel free to try it, it's easy enough. Just disconnect one end link and zip-tie it such that it doesn't flop around.

The "stock" 11k/11k Ohlins DFV spring rates give 25% stiffer rear wheel rate vs. front. IMO, it's not the best spring rate setup. Which is why I went to 13k fronts which gives close to even wheel rates. You might try that, or softer rears.

-1.2 camber all around is pretty low. I run -3 front -2 rear.

I have similar tire stagger to you, 245F/275R. I like to keep the front tires smaller and lighter-weight for street driving feel reasons and because it's easier to fit wider tires in back than in front. Also, with decent power/weight and 50/50 weight distribution, the rears get a lot of heat, so wider rears makes sense. With 245/275 I still put way more heat into the rears and wear them much faster than fronts.

255F/285R seems like a perfectly reasonable tire size setup to me...
I certainly wouldn't run them as 285F/255R!

ItalynStylion

iTrader: (1)

I'm in Dallas too. I had a Red R1 till about 2 years ago (sold it to a guy in Allen). My setup was similar to yours. I had the stock twins, coils, aftermarket SMIC, larger rad, PFC, etc..made about 313whp on Rotary Performance's Dyno.

84-87C is right where that thing should be nearly all the time in normal driving. Obviously, you'll see higher temps at the track. 109c is pretty toasty though. One thing you can do that may yield good results is use a higher pressure radiator cap on the AST and run a bit more water in the cooling system. Water typically has better cooling properties but boils at a lower temp than the coolant. If you have a higher pressure cap it will keep the water from boiling and you'll see better heat transfer.

On brakes, I was running similar pads to you but with the StopTech slotted rotors. I found the brakes to be sufficient at Eagles Canyon Raceway up in Decatur.

j9fd3s

iTrader: (3)

i'll second this.

the longer, but incomplete answer is that tires have a spring rate (hoosier has a chart somewhere, i came up short), and you want the spring rates of the tires to be even, or at least matched front to rear. simple, yes. the tricky part is that very few tracks have an even number of left or right turns, when you add in the accelerations, the tires do not heat up evenly. since a tire gains ~1psi per 10 degrees of temperature, this means that some tires will gain more pressure than others. hence the hot setting.

for the actual pressure number, tires will have a sweet spot, and quite what that is depends on what kind of tire it is, and weight of the car. so the magic number might not be 38psi, but 38psi is a good starting point.

ItalynStylion

iTrader: (1)

Great post! Thanks for taking the time.