Opentrack Willow Springs Dec-03-03

[gmaki]

Just got back from our first track day with our new (to us) 280z. I met Chino240z there and he told about this site so here I am.

My brother and I purchased Dale Shanks ITS 280z about a year ago and have finally got it to the point where we could track it (might tell that story in a long post later). We are not attempting to keep it ITS legal, just having fun going around the track fast (and inexpensively)

All in all things went much better than expected, the car ran flawlessly all day. But the brakes.. sheesh, that's gotta be fixed. At first I thought I had no brakes at all, then my brother told me I had to step on them HARD, very hard. So in fact there were some brakes but still not much causing me to lift and brake very early for all the turns. Still managed to run respectably in Yellow and Blue groups. My brother casually timed me at about 1:52 which is about the same as I ran in my stone stock WRX about 2 years ago. I never timed him but I bet he was a bit faster (stronger right leg and bigger cajones). I think brakes will improve our times quite a bit.

Anyway, had a great time today, can't wait to do it again. And seeing Chino240z's car in person is a treat in itself. That car is SUPER clean. Great job!

Some guy posted pics at: Willow Pics

Chino240z, your car is included here and here

Our car only shows up in this shot which is a good thing cause that's the only distance it looks good from.

[Zvoiture]

Welcome! NEED MORE RACERS! NEED MORE RACERS! Any kind. Hope to run into you at a track soon. Fact: Your car CAN NOT be uglier than mine!

steve77

[2ManyZs]

If the car sat for a year with racing brake fluid in it, it has probably drawn a lot of moisture in it, and you may have a seized piston. I used to flush out the racing fluid at the end of the season and replace it with regular (cheap) DOT3 fluid to prevent this......

Or, you might have pads on it that require a lot of heat to work properly and you just never got them hot enough....

[gmaki]

the seized piston is a definite possibility. I don't think it's the pads though since we ran the car in about 8 sessions today and it ain't hard to generate plenty of heat on the big track at Willow. There was certainly plenty of brake dust on the front rims. We thought the new pads might be the problem early on but braking didn't improve at all throughout the day.

I am wondering if maybe we aren't getting any power assist, to me that's what it feels like, but between me and my bro, I am not the mechanically inclined one.

I'll suggest the seized piston to him and see what he thinks. Thanks for the ideas.

[2ManyZs]

Still would be a good idea just to check the pistons....if the car still has the original calipers, you've only got 4 pistons total, so if one is seized, or just gummed up with corrosion, it makes a big difference.....

As for the power assist, did anyone have the vaccum lines off the intake to the booster? I'm wondering if the check valve might have gotten installed backwards, which would give you no power assist...don't tell anyone, but I did it once myself, that's what I got for being in a hurry...:stupid: The arrow should be pointed towards the booster, and double check your lines just to be sure you have no leaks.

Oh, and make sure your rear shoes are adjusted correctly too, that will prevent you from overheating the fronts.

FWIW, my old ITS 280 is now running with the Toyota 4 piston calipers on the front with a set of cut down RX-7 pads... he says the brakes are no problem now... not that he's running up front yet to get protested in ITS with them...

Do a search for Toyota calipers and you should find many threads concerning them so you can pick up a set off Ebay or a junkyard... I bought a set for 45 bucks and for another 20 for a rebuild kit, they are cheap insurance.....

[Zvoiture]

Originally posted by 2ManyZs

my old ITS 280 is now running

Did I just read this? Maybe I have had too many glasses of wine. I could have SWORN I just read Keith say a car of his is "running".

steve77

[2ManyZs]

Nah, you are just turning into a wino.... time to join Grapes Anonymous.....

I sold that car over a year ago Steve.... it always did run, just needed a few rust spots taken care of and put back on the track.

Of course, after 5 Drivers Schools of 3 hours track time each, and about 15 races (not to mention the 7 years of sitting without being started), the ATK motor finally got a little weak in the compression, and he's gonna have to rebuild the bottom end this winter.... not bad if you ask me eh?

[Chino 240Z]

Hey gmaki,

Glad to see ya here! These guys here on site have been my best help and ideas to get several of the problems figured out. Yes, yesterday was awsome. Maybe we can team up to get a few of these Z cars from this site to show up in the up coming events at Opentrackracing? You don't need a race car, run what you brung! I was blown away by the performance those Mini Coopers put out. Looks like we are going to have to yank those 460s out of the rear. Okay guys we need more top end speed on the straights but don't want to sacrifice the "out of the hole" speed in the turns, so what gear should we be thinking about. I have 3 diffs sitting in the shed, don't know what's in them, maybe we should go new? $ ?

Okay gmaki we'll beat the war drum for the next event and get a troop of Z cars out there!

BTW I second 2Manys motion, get the wheels off, open up the brakes, check em all, freshin them up, upgrade the pads & fluid. We are trying the Portterfield carbon kevlar pad with Motul 600 fluid and big vented rotors and no problems yet. Just noisy as hell when they are cold. Now that we're done for the year that is on the "honey do list" my honey will do it! ha ha ha

Craig

[2ManyZs]

First question is Chino, what trans are you running? What size tires?

Most of the road racers that I know, run anything from a 3:70 to a 4:11 with the 4 speed, and 3:90 to a 4:37 with the ZX 5 speed in this area. But, I don't know how Willow compares to Summit Point or VIR as far as track layout.

If you are running the 4:62 with a 4 speed, and if you can, you would probably pick up quite a bit just by going to a ZX 5 speed.

If you run the 280Z 5 speed with the shorter overdrive, try a 3:90 to a 4:37.

[Chino 240Z]

The car now has (fresh with new sinc-rings and all) 280Z 5 speed with the shorter overdrive (I believe), there is very little differnce between 4th & 5th. Tire size is the Toyo RA-1 225/50/14.

This is where we are lacking in wide open throttle, 5th gear, down a 1/2 mile straight. I did talk to another Z racer at the VARA event and he was using the 3:90 wth good results. I do have 2 more 4spd trans in the shed that I believe are stock so others are available to me to do what ever with . . .

Thanks Craig

[2ManyZs]

Hmm, with a 1/2 mile straight, I'd try a 4:11 with the 280 5 speed. Should still give you good drive out of the turns and you shouldn't run out gear on the straight...With a 4 speed, you'd probably be better off with a 3:90 or 3:70.

Guys at Summit still run a 3:90 with the stock 4 speed but are turning some serious RPM's on the 3,000 ft long straight, 7K plus. But many have gone to either a 3:70 and some even run a 3:54 with the stock 4 speed.

My old 280 had to put a 5 speed in with the 4:11 with the 50 series tires as he was running out of RPM's before the end of the straight, course, the L-28 won't rev quite as high as the L-24 either, at least, not in ITS trim.

Or, you could try a ZX 5speed with the higher overdrive with your 4:62, might make just enough difference. With that combination, you ought to come out pretty close on your final drive ratio as you would with a 4 speed (1:1) and a 3:90 rear.... I'm just guessing at that one as I don't have the formula handy....Tranny swap would probably be a bit cheaper in the long run, plus, you'd have the benefit of quicker accel out of the turns. Depends on lot on how tight the rest of the course is....

As you can see, Summit isn't a really tight course except for in the Carousel, which can slow you down on a a mahor portion of the track.

http://www.summitpoint-raceway.com/SPR.HTM

[Zvoiture]

>>>>down(hill) a 1/2 mile straight<<<<

Yeah, either side at the Willow big track, that is where the 911's go by like you are sitting still.

steve77