PredatorGSR

I wanted to get some feedback from those who have tracked an ITR with stock suspension.

I have an ITR that has completely stock suspension and 205/50/15 RE-11s. I bought it a little over a year ago and am getting serious about HPDE and Autox. I've done 3x AutoX and 2x HPDEs in the last few months. The only adjustments I've made so far are putting on race pads and brake fluid. I'm trying to keep the handling characteristics as stable as possible to give myself a good platform to learn how to drive it properly.

At my first autox, I didn't pay attention to the tire pressure, and ended up running with ~20ish PSI in most of the tires. Not surprisingly, the car rolled over the tires a lot and wore heavily on the outer edge after 1 event, pretty much ruining the front tires. I swapped them to the back, and ran 42 PSI cold pressure for the next autox and an hpde. I also didn't throw the car around as much, and the tires held up much better.

This weekend I did a 3rd autox and another hpde, and monitered my hot pressures this time. At the hpde, my hot tire pressures were above 52 psi after each run, with the max pressure on my tire sidewall listed at 51. I reduced the pressure down to about 48 hot for the 2nd half of the day.

After the weekend, these tires are shot primarily due to the wear on the outer edge even though there is still decent tread left in the middle and inner. During hard cornering, I also feel like I'm riding on the outer edge of the front tires and don't have great stability. The car overall feels amazingly neutral, and only tends to understeer or oversteer when I make driving mistakes that cause it.

So now I'm about to put a new set of tires on (205/55/R15 RE-71Rs), and while I don't want to mess with the stock settings, I want to get full use out of my next set of tires and not scrub the outer edge as much. I've been thinking of taking the car to a reputable race shop and adjusting the camber to something like -2F/-1.8R to counter the wear and improve handling when throwing the car from side to side, which would require a camber kit.

I guess I'm looking for a reality check if this is a reasonable course of action or if I need to spend another tire cycle learning the handling characteristics of the R before I mess with anything. I'm trying to avoid more significant suspension adjustments, at least for the near future because I don't want to **** with the great balance that the ITR has already, and I also don't feel like I'm experienced enough to make more significant changes without potentially disrupting my learning progress or making the car worse.

I'm also curious if this might be a natural side effect of running slightly wider tires, or maybe if improved technique would prevent this issue.

itrSteez

Don't do a thing, 205 RE-11's on stock suspension is a fantastic setup that it will take you many many many events before you're able to out drive it (I did it for years)... And by the time that you do, your senses will be more in tune to how you want to tweak the suspension for you liking.

coolhandluke

iTrader: (2)

I couldn't agree more. Don't change a thing, just focus on seat time.

I just returned my 97' back to stock suspension. It's a blast on track, these are great cars to toss around.

Todd00

Another thing to remember...you're running a wide 205 tire on a narrow 6" wheel (assuming the OEM wheel). You can compensate some with more pressure, but that's about all you can do. You're going to get some rollover.

aw614

and possibly unusual tirewear on outer half with stock 15x6. The re-11's run nearly as wide as a 225 bfg rival...

DC2888

look into a tire pyrometer. It will give you more accurate tire temp readings and from there you can adjust your tire pressure accordingly.

d.n.d.

iTrader: (5)

to add to the list of concerns of tracking a stock ITR reliably, would it be recommended to switch to a baffled oil pan for autoX and track events? Running the same class of tires, roughly UTQG of 140 to 200.

HondaRcB

Autox - no. Tracking - cheap insurance. I never had any fuel starvation issues in my street driven ITR, but I do in my race car with R comps. Have to overfill even with a baffled pan.

d.n.d.

iTrader: (5)

cool thanks, good to know. time to hunt for a baffled oil pan now.

CW-ITR

iTrader: (11)

To op, the stock suspension is basically is a sport spec which is a bit softer than most of aftermarket sport spec suspension. Nothing you can do to it to combat the excessive outer wear when autox or road race. Maximize the tire pressure does help a little. With that said, you either choose to stay with the stock suspension and keep changing tires sooner or go with the stiffer aftermarket suspension and reduce the excessive tire wear.
I learned to race in my R with just a set of H&R race springs for three years before I out grew them. Outer tire wear was kept to a minimum. Take in all the advice, analyze them and go with what you feel is best for you. GL

CW-ITR

iTrader: (11)

Just a caution, steel Moroso oil pan tend to leak after a few fittings because of softer steel material than stock pan. My next pan would be an OEM pan with baffles weld to it.

aw614

I've noticed having a front camber kit with the stock suspension also helps minimize tire wear. You can run -2-3 degrees of camber up front.

Depending on the club you autox with, it might move you to a higher class however.

CW-ITR

iTrader: (11)

So, what is that going to help the inner tire wear when he dd his car off the track?

aw614

I would think running -2 degrees of camber on a daily up front with zero toe, the tire wear is negligible.

yeedub

I've been tracking on stock suspension and I find the car to feel a little vague and loose at the front end when I'm at 180km/h (more than 100mph). Also during heavy braking from those speeds, the car also exhibits a bit of wiggling so you really have to keep a good grip on the steering wheel. There is also quite a bit of body roll through corners, especially long sweepers. The car grips very well, but the body roll has an effect on driver confidence.

CW-ITR

iTrader: (11)

That is expected from the stock suspension. It will get uglier if you take weight off the caR. As I mentioned. the stock suspension has it's limitation. Track beginner should learn with it. But beyond that, it get boring and old. <-- No offense to those that still track with it for years and years

d.n.d.

iTrader: (5)

thank you for the heads up, that is great to know for anyone considering the moroso pan. looks like i will either have baffles welded in or suck it up and get a quality pan like the mugen one.

itr#1334

iTrader: (2)

Mugen pan is just an oem pan with baffles. DevonM on here can put baffles in oem pans. He did my pan in its been great. He added a bung as well.

CW-ITR

iTrader: (11)

^ What he said.

PredatorGSR

Thanks for the feedback guys, I'm probably leaning towards keeping it stock for the next set of tires and see how it goes with carefully monitoring the pressure.

sr-71

same thing with 15x6.5 and just a tad less with 15x7 wheels with your tire size, but it can still get bad pretty easily.

On top of what everyone else said already(all great advice BTW), in my experience, here are a few things you can try to counter or rather limit tire rollover:

-make sure that you are not overdriving and especially coming in way too fast and understeering all along while shooting for the apex because that will just kill tires.

- 16inch wheels with of course lower profile tires(and stiffer sidewalls)

-putting on some less sticky tires(usually not an option when you track your car seriously) or even in some cases combined this with 16 inch wheels and you can get to about the same lap times depending on where you run sometimes, you juste have to drive differently on the track and chose your tires wisely.

-camber is your friend(don't need much)

-stiffer and/or slightly shorter springs

-get a new full adjustable suspension if rollover becomes a serious issue

-or just ease the pace a bit, just a few % will usually do, don't need to be much, still enjoy going fast on track and keep tire wear to a minimum given the circumstances at the same time.

-don't do too long of a stint of consecutive hotlaps, do one or two, then back down a bit for a lap or two...that will not solve the issue,but it may help tires last longer.

-maybe try not to ride too much on the outer curbs depending on the track especially those that are rough or escalator/stair shaped because they tend to wear alot or even cause groves, chunk, rip and cut tires over time, especially in cold weather, I've found.

-for a given size, some tires may be more prone to that for several reasons and some hold up pretty well for a certain number of outings and start to come apart rapidly, while others are more gradual. One thing I've found is that ZII's hold up pretty well when new, but because of the tread design, when they start to chunk on the outer, it gets bad quickly. Now ZII's Star Spec, can't say yet I'm not done killing my last set of ZII yet. I'm not sure if it's the tread design issue that amplifies the problem on our car in this size or the tire compound or a combination of both...I still need to make some more testing. As for RE-71R, be careful because you'll notice that the tread on these is almost a carbon copy of the ZII and could possibly present the same issue unless the compound might be the weaklink regarding this particular issue, not sure yet...so I will have to try and see. With that said they are both fabulous to drive on track though.

yeedub

Just did another track day yesterday. 215/45/16 BFG rivals on JDM 16x7 wheels. I may have over driven my tires a bit but there was some noticeable wear from rollover on the sidewall. I was running 34/32 psi hot.

I could definitely use some more camber but I'm unable to adjust anything due to the stock suspension components

sr-71

IMO 34/32 when hot is way too low for lapping.
Maybe you already knew but just in case, the best way to know is to get a temp gun and I highly doubt that your readings would be equal after a session across the tire patch at this tire pressure.
In short, take tire temp after every run and you'll know.

When I run between 35/33 and 36.5/34 COLD I get temp readings within 2 deg F. after a session on track and it seems to be the sweetspot on every track I went, in dry conditions and at various outside temps, with stock suspension setup.

I've experienced with up to 38/36 still with somewhat acceptable results, at which point the car started to get noticeably more nervous from the back though, still controlable but didn't like it for my driving style and the car started to push on entry and oversteer too easily for my taste on exit, especially on bumpy corners.
At higher Psi values, I started to see more important discrepancies with temp readings.

With lower psi values such as 33/32 the car was easy to control, but tended to get more sluggish with steering input, rollover increased drastically and distances started to increase under hard braking coming at speed. Below these figures temp readings seemed to confirm what I could feel behind the steering wheel as well.
Conclusion: for performance, feel and help against tire rollover, I prefer going towards slightly higher psi values rather than the opposite.

I'm curious to see what others have found...what about you guys?

(BTW I run ZII 205/50/15 on 15x7 and ZII 225/45/16 on 16x8)

yeedub

I started the day with 32/30 cold and by the end of the 20 min session it had gone to 40/36 and very greasy .

I aired down to compensate but do you think that is too much?

CW-ITR

iTrader: (11)

As tire psi goes up with temp, feeling "greasy" is usually due to tire compound react to high temp and loose it adhesion. Backing down the psi only cause more friction and make it worst. Running high psi will always help with tire wear given that you are not over-do it.