Third trackday! All is good!
 

Okay, so the second trackday never really happened ! but I don't want to revisit that old thread and figured I'd start a new one ! So here we go:

location: PIR in phoenix, az
Phoenix International Raceway - Trackpedia
conditions: sunny, 94f
event: nasa hpde4... 4 runs about 20 mins each

Just got home - first, this car is SOOOO much fun to drive when you don't have to worry about overheating ! Lots of control, feels very stable whether I was hanging it out occasionally in the carousel or blasting through the nascar turns on my way to ~120 in nascar straight ! I gained a lot of time going fast through bendies and deceleration zones b/c the car gave me the confidence to hold speed... acceleration was prob less than average for the group I was running with, lots of cars with weight / power ratios in the 6-10 lbs/hp range, but this car held it's own...

First three sessions I only saw max of 255F oil temp, last session I did see 260F... I think I'm going to upgrade to a bigger core than what stillen included in the kit - would like to see them offer two variants, one with an even bigger core and perhaps longer lines so it can be mounted drivers side... which is similar to the technosquare kit i believe

Stillen sway bars performed well, I could feel that the left and right were tied together... I ran firmest setting in the rear, and it wasn't tight enough... Recommend that anyone going with the Stillen sway bars select the tightest fitment for rear for sure... I look forward to getting my bc racing coilovers from DDM - I think I lost some time accelerating in transitions due to body roll... I could also tell the tires were taking abuse with the stock camber settings, they were def rolling over and getting excessively hot on the outside...

The engine performed well... others have complained about the vibration, but to me that's just another form of feedback from the car that tells me where my RPMs are at... I'm happy ! The stillen bolt on parts helped with the power and I could accelerate some in 4th on the big straight... I still want another ~15-20% in power/weight... I owe everyone an updated dyno, but I'm guessing based on where others are at with the same mods that I'm putting down about 305 right now... If I can get to 330 and lose 100 or so lbs on the car and my fat ***, then I should be in the sweet-spot for this chassis and my driving skills

Sound of the car!!!!!! don't know what to say other than WOW... I really love the way it sounds with the full Stillen kit, and I think folks standing around the track enjoyed it too !

People have talked about getting a different final gear, but for this track, gears seemed to be PERFECTLY matched and I was shifting in all the right points... I think I'll pass

I am very frustrated with the mass/momentum of the flywheel... I'm convinced this is the source of my overrevving situation on upshifts... I've managed to get my timing down to where that's minimized, but it is still there even if I dump the accerlator 100% before pressing the clutch... lightweight flywheel will be added to my list

LSD... breakaway is predictable and controllable, but I think it can be better... new mech LSD remains on my list, but not a high priority

Tires held up okay... I've always been a fan of these since I ran them on my old boxster, but it's time to upgrade to some real track tires... if DDM can get those forgestar guys moving, I hope to have a set of 18s + R888s next time out (prob July)

Lots of folks coming up to the car for looks and discussion... and here's the best part ! I think I got a lot of attention in the fourth and final session when I hung with a GTR for two laps and then PASSED IT ! Corner workers were clearly pleased... I managed to get about 10 car lengths ahead before the session ended... woohoo... I think I may have pulled a time in the 1:15s in this session, but I'm not certain - didn't have anyone timing... earlier sessions I was clocking consistently between 1:16 and 1:17... here are some of the top times at this track NASA Time Trial

No video from me guys - sorry... I have a chasecam and traqmate on order through Shariff, but those won't be hear for a week or two... There will be videos and pics that other people take, and I will post them here and in my gallery once that happens http://www.the370z.com/members-370z-...b-journal.html

All for now

Yes, I think the oil temp still sounds too high. On my various past racing cars, I tried to keep the oil temp below 230F, and I really preferred it to stay below 200F, though that's not always a reasonable expectation.

Anyway, congrats on a great rack weekend!

Thanks ! :) Fully agree on the temps, I'm def getting a bigger core

Great writeup... so nice to hear about a trouble-free trackday.

When I drove the Z (still waiting to get mine), my biggest problem with it was that flywheel. It almost feels like there's something electronic going on - it really drove me crazy. I thought I might get used to it owning the car, but it sounds like something to add to my list.

Great results Travis.

How were the brakes holding up? (What pads?) I still can't get mine to behave correctly when hot.

Sometimes in a low torque car (like an rx-7/8) OEMs use a very heavy flywheel to keep momentum and torque... for this car, plenty of torque on tap, so there's no excuse for it IMO... I find that even when casually up shifting on the street, the car is too slow revving down by the time I'm in the next gear the revs are higher than they should be when I let out the clutch - if that makes sense... JWT flywheel will resolve the matter

All sounds great Travis. Now get it back to my shop for everything else!

Cheers,
Robert

I think you're right... How could I have forgotten to talk about the brakes ! hp+ pads

Thing 1... I could almost swear I'm getting a variation in stopping force from left to right... may just be that I'm trail braking and feeling it step out ever so slightly... but just didn't feel entirely balanced... could be related to thing 2

Thing 2... When they were at lower temps, they stopped really really well and predictably... but later in my sessions I was getting MAJOR fade to the point that ABS was kicking in and I was grinding to a halt going into turn 9, which is a 100+ degree left hand transition from infield road course to nascar circuit... I commented earlier that the stock rotors are fine, but now I don't think so... not at all... NEED SLOTTED ROTORS !

Robert, great job with the car !

Folks, let me introduce Robert Boreham, proprietor of Redline Motorsports in Tempe, AZ... Robert is a former Porsche Motorsports NA mechanic and a fellow enthusiast! He will be looking after my car going forward. Welcome to the board !

And yes, I will have it back tomorrow night ! :tup:

Great report Travis, glad you had so much fun!

On the oil cooler, do you know which of these ships with the Stillen kit?

Thanks,

thanks Miguez... read some of these
http://www.the370z.com/nissan-370z-g...ll-thread.html
http://www.the370z.com/members-370z-...z-journal.html
http://www.the370z.com/intake-exhaus...es-plenty.html
http://www.the370z.com/members-370z-...s-journal.html

half way down the third you can see it is 11x6

Thanks Travis, I subscribe to all those threads, but my question was, more specifically, how many rows does the Stillen kit cooler have? If you look at the link I sent you, the Series 6 Setrab coolers vary from 10 to 34 rows. There is also a Series 9 25 Rows cooler for sale at that site.

I was wondering how many rows, since it is possible you might keep the same core size, by buying a core with more rows. If you notice on that site, all Series 6 cores have the same dimensions, even though they vary tremendously in the number of rows.

One thing I wonder about.. If we swap in a light flywheel, do you think there would be adverse effects to the SynchroRev function? Over compensation on it's part maybe?

I think Nissan went with such a heavy flywheel to let people grandpa-shift.. Nissan will still unfortunately cater to the majority crowd over the racing crowd.

I'd have to go and research it... going to let you do that ! or someone else can answer :)

This has been discussed in other threads a lot... consensus seems to be, 'should be fine' b/c SRM is really targeting an RPM and will do its darndest to get there one way or another regardless of conditions in the powertrain... but proof will be when one of us does it ! you're right re Nissan's design target, unfortunately not us !

LOL, got it. Maybe Josh (Stillen) can help out?

Travis, what did you mean by the bold section above/ Is this an option when buying and/or installing the bars?

Thanks,

I hear you about the flywheel - it feels like the revs are being held up above what they should be for some reason. I've driven Bimmers that did that, and it just makes me feel that much more disconnected from the car. My goal in shifting is to try to make the transmission do as little work as possible, which means matching revs, and these grandpa modes are a PITA.

And: brake fade? Maybe Nissan didn't put oil coolers on the car so people couldn't run enough laps to realize that the brakes faded. Once we upgrade the rotors, the differential will probably melt... It reminds me of the recent Shelby 500 press weekend, where it was obvious that the reason they didn't give the press more than one lap at a time was so they didn't discover how badly the brakes fade.

I'm still leaning toward buying the car, but I'm a bit disappointed that it takes so much work/money to get it trackworthy... really appreciate the detailed writeups from you and RCZ though...

HP+ pads aren't exactly a track friendly pad. They are in the same category as Ferodo DS2500's IMO (street/track). For 20 minute sessions you need to run a Ferodo DS3000 or a PFC-01 or something with else with a high heat tolerance that is meant for track duty only.

Most sway bars are adjustable for how much pre-tension is put on them... there are some good resources that describe this on the net if you do a couple searches... search on car bible, suspension, sway bar for example

Ha ! funny you say that, exactly why I was so high on the brakes last time out... never spent more than 10 mins on the track until i got this oil cooler installed

Look, I'm still recommending this car - I want ppl to know that!! I really enjoy driving it, and for comparison I have about 50 hours of track time in a mid-engine porsche, 15 hours in a corvette, and 5 in a formula car... I'd put this one tied for first with the formula car! ... and a leg up for practicality (drive to track). I think you could get away with simply adding an oil cooler, a few routine safety items, and maybe the right pads, if you really wanted to. I'm just looking for more.

Appreciate the recommendation, I'll look into these... do you know anything about the compound difference that causes the difference or are you going on personal experience?

Travis, hit me up on Monday.. we have an entire brake division who is fully versed with track pads, compounds.. you're at the level where you're far exceeding the needs of the typical guy, I'd like to extend some of the resources we have available. I'd be interested to set you up with our Brake Manager to hammer out some of your needs, as at this point you're probably the main person I've seen take the 370Z to the limits of the factory brakes.. if you're going to continue to track the car in the current form with the factory brakes, it would be interesting to see what compounds are available, how easy it is to swap pads, etc. to give you some additional confidence in the brakes..

I personally think you're ready for an AP Racing system.. but we can talk about that.. :bowrofl:

I *hope* there's a way not to resort to track-only pads. I'd be interested to know if the Carbotechs work better.

Probably the fact that I have much less track experience than a few of you will help me out - I won't be able to get the speeds up as high, which means less fading ; ).

I feel like once I get to swapping pads, tires, and who knows what else every trackday, it gets a little less fun. I'd rather deal with the lower times in most cases in order to be able to drive in, track the car, and drive home, without garage time. The alternative to me seems to be to get a dedicated track car, and that's a whole other ball of wax...

I'll give you a call today or tomorrow... also, feel free to call Robert at Redline and talk it through with him... thanks Josh!

Thing 1 is possibly related to thing 2 and trail braking which might make for a temperature differential left to right.

Thing 2 sounds almost exactly like I was experiencing, I have experienced this on the stock pads and with the Hawk HP+. It's not regular brake fade however, as if it was truly fade the ABS wouldn't be kicking in at all and you're pedal would be heading for the floor.

My theory is that once you got the tires and brakes up to full operating temperature there was so much stopping force that the ABS computer didn't know what to do with it. It over-reacted and reduced braking force by pulsing the front ABS at a high rate. I think the ABS computer needs to be reprogrammed to account for the added grip. Adding more grip and/or bigger brakes may only make it worse. I think the stock calipers and rotors are probably fine. Brake ducting would probably be beneficial.

Interesting theory... I can't find anything online that's similar for other cars, but it's semi-plausible. The ABS would read the rapid deceleration as a partial lockup...?

It's just a theory at this point. Would need some data logger results to show that braking deceleration was increasing (improving in terms of -G) and then a sudden drop off when it reaches a certain threshold. Any more detailed information on the ABS system employed in the 370Z would also be useful.

I think it is a 6 series with 19 rows. Looks like the next size up will be the 6 series 25 row.

The pads aren't that hard to swap out. It might be something I'd not want to do at PIR in July.

After Dave Schardt drove my car at Mid-Ohio for an oil temp limited amount of time he was of the opinion that it needed a set of PFC/Hawk/...track pads. The calipers might hold up. The dust seals on the pistons will most likely be toast in short order.

I could find Carbotech XP10's for the front but there were no XP8's for the rear. Seems the rear blanks are a bit hard to come by.

Agree, a caliper upgrade with more swept area would be a nice upgrade. It would definitely help in the fade department. A wider caliper with a bit more pad wouldn't hurt either.

Josh has been working with me to piece together a modified oil cooler kit that includes a thermostat as I'm in Chicago. I'm sure that he can price out a kit that includes a 25row core for those who are in need.

That's good. I have to say, I'm a bit disappointed at Stillen that their cooler wasn't sized properly to begin with. It should have been pushed hard at the track - after all, hardcore track users are the people who will be buying it.

Oh well, that's what early release stuff is all about I guess. At least they're serious about follow-up...

I'll second that. Josh contacted me and offered to get one of the first coolers to me in time for Mid-Ohio. He also indicated that they could offer some upgrades if wanted them.

My guess is that the current cooler will satisfy a lot of people. Travis may be in one of the hotter spots for tracking a car. Swapping out the core will not be a difficult job and most likely won't be too hard to find a buyer for it.

my mech offered to buy it, but in the end, we've instead decided to double-down on cores! will likely install an identical core in series on driver's side... if that doesn't do the trick, not sure what will

Damn - dual cores puts the price at $1100, plus install. They'd better work ; )

I'm not paying that much, but regardless I think it is worth investing in this area for those using the car at the track a lot, esp in hotter climates like AZ and SoCal

Here's a pic of me catching a boxster spec car
PhotoReflect - DGP Photography
http://i656.photobucket.com/albums/u...b/Untitled.jpg

Personal experience. There is some info on the performance friction website IIRC. Might be some more info on other manufacturers websites about different compounds.

Sharing more pics of my last event at PIR... enjoy!

http://i656.photobucket.com/albums/u...visjb/pir1.jpg
http://i656.photobucket.com/albums/u...visjb/pir2.jpg
http://i656.photobucket.com/albums/u...visjb/pir3.jpg
http://i656.photobucket.com/albums/u...visjb/pir4.jpg
http://i656.photobucket.com/albums/u...visjb/pir5.jpg
http://i656.photobucket.com/albums/u...visjb/pir6.jpg
http://i656.photobucket.com/albums/u...visjb/pir7.jpg