Track Day September 12

[MountainRunner]

You are right, there was a trap speed at the start / finish line. The speeds recorded were about 10% fast on the day. I am still calibrating the system. It should be spot on next track day and I plan to have my big electronic sign back showing the trap speeds live.

I haven't recorded the data in an easy format for publishing, although I do intend to mail everyone a timesheet in PDF soon which will have the trap times on it.

Paul

[Col-GTSX]

I found the trap speeds to read about 10-15 kph faster than my spedo was reading across the start/finish line...

BTW. I will give ya a hand again next tme Paul. I thought its worth helping out for a afternoon of fun. However this time i think i want to attack the national track.

I have ordered whiteline sway bars and im looking for some semi slicks before the next race day, i should be good to go harder...

[nF]

Im already thinking about the november day...

I cannot wait till i can unleash the yellow beast...

My top speed down the back straight was 224kph in 5th. My top speed in 4th was 198kph bouncing off the rev limiter. But my brakes were crap and my street tyres would not let me turn without drifting. So next time ill have bigger brakes and hopefully semi slicks... Oh and a bigger turbo of course...

that sounds way too high

[Col-GTSX]

that sounds way too high

I guess Pfc's lie then...

You know those Pfc's that take their reading straight from the speed sensor on the gearbox???

[MountainRunner]

Hey Col-GTSX, just to clarify, you are claiming those high speeds on the back straight on the National Circuit / Sprint circuit right. In which case I think the 200km/h + are probably correct. What do others get ?

Survey....

My speed trap is on the front straight at the start/finish line. The usual speed around there is 170km/h with the more hardcore cars getting near and just over 200km/h.

Paul

Paul

[hrd-hr30]

Hey Col-GTSX, just to clarify, you are claiming those high speeds on the back straight on the National Circuit / Sprint circuit right. In which case I think the 200km/h + are probably correct. What do others get ?

Survey....

My speed trap is on the front straight at the start/finish line. The usual speed around there is 170km/h with the more hardcore cars getting near and just over 200km/h.

Paul

Paul

I only recall looking at my speedo once on the back straight on the Sportsman circuit in the afternoon. It was up around 220kph. 170-180 sounds about right for my car by the start-finish line, I was pulling 4th just before it.

[Col-GTSX]

Hey Col-GTSX, just to clarify, you are claiming those high speeds on the back straight on the National Circuit / Sprint circuit right.

Yeah... As i said earlier the front straight was round the 170kph area. I was doing about 160ish when i passed the speed trap which i call the front straight... I ran the back straight at full noise in 4th bouncing it off the rev limiter and the pfc recorded a max speed of 198kph at rev limiter. Then the next lap i ran her to rev limit and a bit into 5th gear and pulled up with millimeters so spare beofre the sand and recorded a 224kph. This was getting every little bit out of my car down the back straight.

Also i turned the boost down to 12psi (which in my car produces around 200rwkw) for the track day due to wanting to be able to drive home....

[AzzurrA]

down the back straight, according to my speedo, i was winding it juuuuust off the clock (180kph) in 5th by the time i was braking (150m mark)

edit: 184kph according to my consult reader

[Space Ninja]

Yeah... As i said earlier the front straight was round the 170kph area. I was doing about 160ish when i passed the speed trap which i call the front straight... I ran the back straight at full noise in 4th bouncing it off the rev limiter and the pfc recorded a max speed of 198kph at rev limiter. Then the next lap i ran her to rev limit and a bit into 5th gear and pulled up with millimeters so spare beofre the sand and recorded a 224kph. This was getting every little bit out of my car down the back straight.

Also i turned the boost down to 12psi (which in my car produces around 200rwkw) for the track day due to wanting to be able to drive home....

Just out of curiosity, what other mods are you running in your car Col? It seems pretty similar to what I have in mine, yet I wasn't getting up to those sorts of speeds on the Sportsman circuit (I didn't run national). I'm also running a little bit less boost than you but was posting better sprint times as well - just curious thats all.

Edited September 18, 2006 by Space Ninja

[nF]

I guess Pfc's lie then...

You know those Pfc's that take their reading straight from the speed sensor on the gearbox???

don't get cranky dude

i just think its wrong, you did 200 one lap, then 225 the next that doesn't sound a bit odd to you

[MountainRunner]

The terminal speed on the back straight will have a lot to do with the turn 1 and turn 2 speeds, especially the exit speed out of turn 2. If you can imagine a 20km/h variation out of those two corners then I can see it at the end of the back straight.

Further commentary Col ??

[r33_racer]

The tower sees all. As always corner exit speeds greatly affect times and straight line speeds.

Paul are all the times upto date? Do you run in the sprints or Top gear at QR? or anything else for that matter? Also do you have a relative with your last name thats a mechanic and in their mid to late 40's or would you be by any chance?

haha or am i way way off?

[nF]

The tower sees all. As always corner exit speeds greatly affect times and straight line speeds.

Paul are all the times upto date? Do you run in the sprints or Top gear at QR? or anything else for that matter? Also do you have a relative with your last name thats a mechanic and in their mid to late 40's or would you be by any chance?

haha or am i way way off?

acceleration is parabolic though

corner exit speed wouldn't make up 25km/h in my opinion, hence i said i think its wrong

[Col-GTSX]

Just out of curiosity, what other mods are you running in your car Col?

It a compresensive Rb25. No rock unturned other than the head. The bottom end is forged and all the supporting mods have been put in place for 350rwkw... I just have not recieved by new injectors yet and im having touble getting them out of neugun atm... I have a GT30 high mount with a 0.82 rear going on before the next track day.

I also have to order cams, but other than the turbo, head work, injectors and cams i have done everything basiclly.

I ran boost on my lower setting of 12psi (it is a high flowed stocker). At this psi i get 200rwkw even on all stars dyno. At 14.3 psi i get round the 240rwkw mark with a bit of extra timing. Matt spry is the tuning legend who did all the pfc work to my car and we achieved a massive 520nm of torque at the sau qld dyno night.

JBoy was the only car with a high torque figure... I beat 2 other GTR's in the torque department. I owe it all to tuning and the build of the engine. Just need those injectors and im ready to rev limit 5th down the back straight...

don't get cranky dude

i just think its wrong, you did 200 one lap, then 225 the next that doesn't sound a bit odd to you

Yeah sorry i was a bit rude before. I guess i shoudl explain a bit better.

I ran the first time on the track 2,3,4 gear only never used 5th at all. Pfc read 198kph at the end of that session. The second time on the circuit i used 5th gear also and pushed the car to the limit down the back straight. I exited the 2nd turn at about 100kph (bit slow but thats the best i could do on street rubber).

When i got back to the pits i read 224kph on the pfc. The back straight is most certainlly the fastest part of the track so thats where the highest reading must have been recorded.

Remember Pfc reads from the speed sensor straight from the g'box so its as accurate as possible. I would give it a 2-4% varience tho due to tyre diameter and so forth...

The terminal speed on the back straight will have a lot to do with the turn 1 and turn 2 speeds, especially the exit speed out of turn 2. If you can imagine a 20km/h variation out of those two corners then I can see it at the end of the back straight.

Further commentary Col ??

I think i summed it up in the above post.

I was very happy with the straight line power of the car. I even gave J-Boy a push down the front straight just to see how hard it could go. He pulled away but not by much, i just dont have the corner speeds of other cars out there. I do need to work on suspension a bit and i really need some better brakes (i almost didnt make it from 224kph on the back straight into that right hand bend).

Any which way you look at it, it was so much fun and was worth it for the testing on my car. My car is currentlly set up for drag racing and has seen a 12.2 at willowbank only 3 weeks ago (on street rubber, same tyres as i used for track day). My car on the 12th was setup the same way as i ran 12 second except a little less boost as i didnt want to fry the clutch or the turbine round the track. I believe the track is harder on the car than drag racing.

Once again i cannot thank Paul enough for a very professional track day.

Which i cannot suggest enough to others to come along.

Im hooked on Pauls days and will be out there next time with my G-Tech to messure G force i think...

Im not one to worry about lap times or top speeds i just want to have fun and spank a few cars, just to make me feel better.

Cheers Col

[MountainRunner]

r33 racer, your questions:

Paul are all the times upto date?

YES, you can now download all the lap times from the website http://www.timeattack.com.au/lap_times.php

Also the top ten and the hall of fame have also been updated.

Don't forget to also download the Temperatures for the day, I measure the air temp and road surface temp for those who have to know (or is that just me, lol)

Do you run in the sprints or Top gear at QR? or anything else for that matter?

NO, my car has been broken for over a year and a half now, although now that Mick from Signature has it, I am nearly back in the game. Hoping to put in a few laps on November 28.

Also do you have a relative with your last name thats a mechanic and in their mid to late 40's or would you be by any chance?

I am an Electronics Engineer (I built all the timing gear, the 4WD Controller in maccatacks car and some other projects coming soon). I don't know of any mechanic's with the surname Ruzic, or in fact anyone who isn't one of my cousins. lol.

haha or am i way way off?

Who were you thinking of ??

On the back straight speed issue, I agree that an extra 20km/h entry speed will not equal an extra 20km/h exit speed as aerodynamic drag is a cube law, and is definately a factor at 200km/h. I was trying to point out that the speed through turns 1 & 2 will have an effect on terminal speed. Engine tuning will also play a roll on how the car pulls out of turn 2 and accelerates down the back straight. The exit speed at turn 2 will determine if the gearing (rpm point) is in the sweet spot for acceleration as well (be on boost rather than spooling up as this delay would cost terminal km also).

Paul

Edited September 19, 2006 by MountainRunner

[hrd-hr30]

irespective of areo drag and parabolic accelleration and all the other theory you can throw at it, the point is that without going substantially faster through turn 2, you can't realistically go 25kph faster by the end of the back straight. Unless you were bouncing off the rev limiter by half way down the straight the 1st time, or you added a JATO rocket for the second run??? 25kph is a massive difference considering you were coming out of turn 2 at ~100kph and one time added 100kph, the second time you added 125kph! You didn't say anything about coming out of turn 2 faster, so you can hardly blame the guy for being sceptical. It doesn't make much sence.

The only things the track is realy hard on are oil temp, brakes, and tyres - they're consumables and fairly easy to address anyway - well except tyres. Drag racing is a major risk of breaking driveline components. I can't see how the circuit is hard on clutches unless that's just your driving style. slamming every gear change isn't going to make stuff all difference to a lap time anyway compared to getting the braking points right, the lines you take, and the corner and exit speeds you carry.

Edited September 19, 2006 by hrd-hr30

[Col-GTSX]

Unless you were bouncing off the rev limiter by half way down the straight the 1st time,

It doesn't make much sence.

I can't see how the circuit is hard on clutches unless that's just your driving style.

Yes my car bounced off the rev limiter in 4th gear for about 3-4 seconds before turn 3. The reason i did it was to find out what the top speed was in 4th gear. No other reason other than to answer a question in another thread. Where a user claimed to be doing 220kph in 4th gear at red line, he said it was due to his r33 being a series 2. To my understanding the gearbox's are the same in s1 and s2. So i decided to run in 4th at rev limit to see how fast rev limit takes you. I can confirm that at 7000rpm in 4th gear you will reach 198kph.

Does that make sence?

As for the clutch, some users will understand. I fried my clutch at the last drag night we had, i have not changed the clutch at all due to lack of time. So at 240rwkw it will just slip the clutch now due to the wear on the surface. But if you turn the boost down and bring the timing back a bit my clutch holds strong.

Does that make sence?

Sorry but i get really touchy when people question my coments. I may not explain myself very well sometimes, but thats just cause i think others will see what i mean with out writing a heap of stuff. Im not on school holidays and im not trying to convert your religion. Im just talking about my track day experience.

Cheers Col