2nd HPDE, Dinan stg2 and the nannies

[135gofast]

Is Dinan Stg2 and HPDE with DSC off a recipe for limp mode?

I recently attended my 2nd HPDE event at NHMS. I gotta say, HPDE is awesome. It's a little unnerving driving at these events with such an expensive car, but that is why for the initial sessions i press the DSC button only once.

The weather was very nice, about 80f and not too humid. My 135 has Dinan stg2, vorshlag camber plates set at -1.7 camber running stock 215 front & 245 rear RE050 rfts. (Yes, i have APEX ARC-8s with 245 fr & 275 rr Hankook V12s - but the hankooks SUCK, imho. The front 245s are sidewall worn from 4 autox events this season. i prefer the smaller RE050 rfts to the Hankooks soft sidewalls.)

We run the first few laps wth the instructor checking out whether i can drive the line at the track and gradually pushing harder and harder. No problem, first session was great, had a lot of clear laps after passing that one little green miata whose instructor and student were clueless to the line of cars behind them (this was a point-by only passing club).

Session two I push myself harder and lap times drop by 4 seconds, consistently. I feel more comfortable with the line and car, my autocross experience really helps with car control.

Session three: my instructor and i agree to turn of DSC completely and to work my heel-toe downshifting, while driving 8/10ths instead of 10/10ths until i'm comfortable heel-toeing on those oh-so-fun 120mph-50mph ABS-inducing stops. Ok, first lap - LIMP MODE on the first straight while accelerating from about 60-80mph. wtf??? my HPFP is only 6 weeks old, ***having failed at this very spot on the track 6 weeks prior***! this is bad deja-vu.

Pit and stop/start. No codes, no problem. turn on dsc completely. Hit the track. Limp mode again. Pit again. I think my day is over, the car did this to me last time at the track. Instructor wisely suggests going back to just single DSC press, like we ran the first 2 sessions. It's either that or call it a day :-( So i try again, just press DSC once. I short shift around 5,000rpm in all gears to not push the engine too hard, hoping to stave off any more limp mode events, and besides, the goal of this session was to work my heel-toe downshifts. No problem, the car behaves fine the rest of the session. My fastest lap time while heel-toeing and not pushing to hard is .8 seconds of my personal ftd.

Session four: DSC once only. 10/10th driving and out at the front of the group, got in alot of laps. The brakes fade somewhat during the session, but i have amazing fun and post my personal ftd!

So the question is, is Dinan Stg2 and HPDE with DSC off a recipe for Limp Mode? I am sure nothing was too hot, maybe too cold for full throttle, but less than an hour between sessions, the gauges showed temps were still in normal range.

[pixelblue]

I may be wrong but I don't see the connection between DSC DTC and limp mode. btw 10/10th in your mind could actually be 8/10th in reality. not meaning to rain on your parade but honestly I don't think our cars are that stable to drive at 10/10th unless you have a race setup like the Berk car or the ER car. just saying...

ps. might be a good idea to buy a gopro cam so you can document your mad driving skills

[Xaeryan]

Originally Posted by 135gofast

So the question is, is Dinan Stg2 and HPDE with DSC off a recipe for Limp Mode? I am sure nothing was too hot, maybe too cold for full throttle, but less than an hour between sessions, the gauges showed temps were still in normal range.

The gauges don't show the contributor to limp mode; coolant temp. The BMW Power Performance kit addresses this with an extra radiator and fan in the fenderwell. I'd be interested in hearing from some guys with this kit who track their cars to see if it has completely removed limp mode occurrances - it may be worthwhile to get just the radiator/fan/hardware if it can be purchased separately (and assuming the fan is triggered off the stock harness and not something specific to the PPK flash).

And I agree with previous poster - I don't think DSC has any relevance to going into limp mode, although the extra stress of the Dinan tune probably does a lot. And 10/10ths with these cars with just your mods is a mess of mostly understeer with some oversteer in there for good measure. ;-)

[135gofast]

Yep. 10/10ths for me is unique to me and whatever that amounts to probably doesn't matter and probably does not equate to mad skills after only two track days. Still a hero would be cool. . The car still went limp only when dsc was totlly off an just trying to make sense of it

Any body else with Dinan stg 2 experience this problem?

[pixelblue]

did you notice your oil temp being up when in limp mode? apparently it goes into limp mode over 280 or 300. in any case that's where the problem lies. you should also invest in dinans oil cooler and intercooler. without these additional mods your engine is just generating more heat than already normal high temps and can easily clip the 280 mark.

[135gofast]

i was not paying attention attention to the gauges for too-hot, rather for too-cold because it was the start of my 3rd session. there was at least 40-60 minutes of cool-down between sessions. is it possible to have been 280-300 hot on my first lap? maybe i just WOT'd it too soon before it was warmed up?

[pixelblue]

our cars get up to heat pretty quick. I have heard other people going into limp mode within a few laps. think about it, your car is generating 30% more power and we know what more power means. the problem with all these tunes are the cooling is not addressed well. one small trick you can try is turn on your heater to full blast. close the center vents and vent out the sides through your window. you are basically venting off engine heat. another thing you can try is add a bottle of mocool coolant to your radiator reservoir. it's advertised as reducing up to 30 deg. I have tried this and I can say it helps a little but maybe not 30 deg. you need to start thinking cooling off. there are many methods and you can start experimenting. thats half the fun

[135gofast]

full power heater in a black on black 135 = driver limp mode, even with only the outer vents running. gotta look into your other options, mocool and an another oil cooler, iirc, the positioning of the dinan extra oil cooler interferes with the vorshlag camber plates at full negative camber, so not sure how that'll play out.

my mod list priorities may have to change from m3 arb, upgraded brake pads, coilovers and RE11s to something else to do with cooling.

btw, how do your pss9's play with the vorshlag camber plates? You get any "rattling" from them?

[Evice]

how many minutes did you idle your car before hitting the 1st lap ? You may not be at the operating temperature yet to drive around all out. This is one guess.

Logically, when DSC is turned off, you are delivering more overall power than active. However, DSC really have nothing do to with your engine unless you are really rotating the car and DSC kicks in and cuts the power, which at this case it should help your car keep cooler but still very small factor.

135s general lacking point is cooling, you may have hit this barrier. My N52.. rev it at 6.5k forever it is all good
----
Some advice; never drive on your 10/10ths on HPDEs unless you are very experienced -advanced group per se -, just because you don't have the skills yet to recover from tricky situations, let your experience build up. This might be just as simple as a car infront of you oversteering while you are in the corner at your unprepped car's limit.

[pixelblue]

it's not too bad. my last track session ambient temp was 98 deg and I had the heater full blast. it's tolerable for half an hour. pss9 have really transformed the car. I am sure any good coilover will have the same effect. brake pads and brake fluid is very important. make sure you swap in some upgrade pads and fluid before your next track day. you can hold on the coilovers for now. not sure about the oil cooler interfering with the camber plates. it shouldn't be anywhere near them. it's supposed to replace your existing oil cooler in front of your front right wheel. one last thing, change your engine oil to something like motul. they are an upgrade to the oe synthetic and it also helps the engine run a bit cooler in addition to protecting your internals better.

[135gofast]

Originally Posted by Evice

how many minutes did you idle your car before hitting the 1st lap ? You may not be at the operating temperature yet to drive around all out. This is one guess.

Not many, maybe 5. If it were too soon, that would make sense to me, rather than too hot. I probably could do a warm up lap next time.

Some advice; never drive on your 10/10ths on HPDEs unless you are very experienced -advanced group per se -, just because you don't have the skills yet to recover from tricky situations, let your experience build up. This might be just as simple as a car infront of you oversteering while you are in the corner at your unprepped car's limit.

point taken. it was awesome to heel-and-toe on the track, but when things got too interesting, i just skipped the downshift to make sure braking was complete and even though i earned my solo license that day, i plan on taking instructors for a while longer. too much to be learned!

[135gofast]

Originally Posted by pixelblue

it's not too bad. my last track session ambient temp was 98 deg and I had the heater full blast. it's tolerable for half an hour. pss9 have really transformed the car. I am sure any good coilover will have the same effect. brake pads and brake fluid is very important. make sure you swap in some upgrade pads and fluid before your next track day. you can hold on the coilovers for now. not sure about the oil cooler interfering with the camber plates. it shouldn't be anywhere near them. it's supposed to replace your existing oil cooler in front of your front right wheel. one last thing, change your engine oil to something like motul. they are an upgrade to the oe synthetic and it also helps the engine run a bit cooler in addition to protecting your internals better.

pads and fluid upgraded before next event - great advice. making it stop is job #1!! i'm thinking Hawk HP+ and will check out motul fluid.

the suspension feels fine to me on the track. for autox, body roll is a problem for me personally, it doesn't feel fast. still, my awareness that the car can do alot more than i can make it do should prevent me from moddin it too much. maybe an M3 front arb.

one big draw for coilovers for me, is eliminating the rattle inherent with the vorshlag plates when using OE upper spring perch. apparently when using coilovers, there's a different upper spring perch used, eliminating the rattling.

[Evice]

good good! Always take it easy at the beginning, put some heat into tires, some heat into brakes, heat into "your brain" as well for that session. You will see that your speed is going to increase as you smooth your inputs. And as your speed increases, heel-n-toe may be the least important thing that you need to focus on while on track, your focus should be at a level where you can see flaggers while looking 2 turns down depending on situation. you got the idea!

[arrutled]

I think you need to get a secondary oil cooler. Or PM the Berk guys and ask for their opinions. They always help me out.

[135gofast]

Originally Posted by arrutled

I think you need to get a secondary oil cooler. Or PM the Berk guys and ask for their opinions. They always help me out.

hey andy, i didn't even think to check out Dinan's site. Here's what Dinan says:

"The results of the oil cooler upgrade are quite significant, with the temperature gauge holding steady even under high load/high boost scenarios. And for those of you who track their cars, even occasionally, the Dinan oil cooler is a must. "

Well, there you have it, another $1,600 in mods required!

[pixelblue]

that was my original recommendation. glad you came around to it

[135gofast]

yeah, i suppose you're right!

hey, i'm considering some coilovers, because my vorshlag plates rattle like quarters in a tin can and the upper spring perch is the issue. do you know if you're using the OEM spring perches in your pss9 set up and whether you get any low-speed rattling on the passenger side?

[pixelblue]

I don't have any rattling. it's not the spring perch but the top hat and you need to buy their custom one. you will need their custom nut as well for the pss9 application. may want to check into that. doesn't sound right and maybe your rattling issue

[135gofast]

Originally Posted by pixelblue

I don't have any rattling. it's not the spring perch but the top hat and you need to buy their custom one. you will need their custom nut as well for the pss9 application. may want to check into that. doesn't sound right and maybe your rattling issue

If your are using the vorshlag coilover upper spring perch, then you wouldn't have any issues.


i am currently using the oem upper spring perch, and after 3 trips to two different installers AND a stripped right front strut from over torquing the strut top nut, i'm pretty sure it's the oem spring perch. either that or i am just overly fanatical about new noises that arrive along with installing mods.

in any event, i've learned to live with it because i love the look of my wheels and fat front tires.