lionking

Looks like fun Frosty but Mrs LK would kill me if I soiled my undies.

DavidM

The American reckons we can get 60' in 2 sec flat by riding the Clutch because you'll get a lot less wheels spinning.

That makes sence. Afterall, that is roughly what the auto does with it's stall/torque converter ... it (in a way) rides the clutch off the line so that they do not drop bellow ~2500rpm. I was pretty obvious at Calder, that on the surface that they have there, the most grip you have is when not spinning the tyres (ie. as LK was able to do).

Though I'm not good at riding the clutch, so (for me) it seems like a difficult thing to do (and get right). I am very much conditioned to spend as little time on the clutch as possible, and that is my 'natural' driving behaviour. I'm thinking that for me what might work for me at Calder is to ride the clutch to get the car moving (ever so slightly) and then dump it ... I'm thinking that the initial forward momentum might translate to a better 60' time.

Why don't you check out on the Drag Section. There is a lot of tips on how to Launch the 350Z manual properly with Street tires.

I will do that.

I was getting some awesome launches. Out of 9 or 10 runs - did so many I lost track - and a couple of slips, 60-70% were near perfect launches. The auto was making this very easy compared to the manual guys.

I could not agree more. The Auto 350Z was so well suited to launching to Calder's surface that it was making a mockary of us manual guys. Not only could LK get a much better 60' time, but he often could manage 1/2sec or better reaction time. Also, from the comparos that me and LK did between our cars a while back, we concluded that that the Auto 350Z was quicker than my manual 350Z (with hi-tech) between 140 and 160kph due to the gearing differences. Combine those 3 things and LK was consistantly getting better 400m times than the rest of us. Refer to https://my350z.com/forum/showthread....threadid=60733

LK and me never lined up at Calder, but my best time is ~0.19sec sec slower than LKs, so that should see LK about 8.4m ahead of me (ie. close to 2 car-lengths) at the end of 400. Which is not what things looked like when we were lining up previously ... there it looked like I could out-launch LK by about 1/2 car-length, and translate it to about 1 - 1.5 car-length by 160kph. I'm guessing that at Calder things would very much be reversed. Shame that the time-slips do not show the speed at the 60' mark as that could tell us what the 0.2sec gap (that LK has on us) looks like. I'm guessing that the speed there is ~40kph ... if that is the case, then the 0.2sec gap at 60' mark would be 2.2m (ie. 1/2 car-length).

DavidM - good to see you got another 10th in that last run. Not much more to shave off for a 13sec run!!!

Yep, was good to shave off another 10th, but disapointed not to be in 13s. Though, the trap-speeds and 60' times interest me more at the moment as I can see a how the trap-speed and 60' time combine for a 400m time (ie. keep the same trap-speed, drop the 60' time and watch the 400m time dramaticaly improve). As I mentioned before, if there is a way to get 2.0sec 60' time out of the manual 350Z at Calder, then we could be looking at 13.6sec pass for my car.

Could everyone post their 60' times and trap-speeds?

Wow stock 350Z auto with 2.5 - 3 car lengths over the next best modded 350Z is very impressive.

I'd even say that it would be even more than that if you take the reaction-time into account as well. LK's best reaction time was about 0.4sec better than my one, so I'd say that if you took my best run, and lined it up with LK's best run, then LK would be ~0.6sec ahead of me whenwe cross the finish line ... that's like 26m (ie. ~6 car-lengths). That is despite the the fact that our 400m times would have been less than 0.2sec appart.

Which reminds me of the run where I lined up with Ypwpat. In that run I run ~0.4sec quicker time than Ypwpat (ie. 14.224 vs 14.654), but I crossed the line only 0.85sec ahead of him (ie. 3.7m, which is less than 1 car-length). I remember that run pretty well, Ypwpat had a 0.35sec better reaction time so he shot ahead of me. I had a better launch though, so I cuold him pretty quick and by the time we shifted to 3rd gear, I was about 1 car-length ahead and it stayed like that all the way 'till the finish-line. I'd say that there was nothing between us in terms of acceleration once we were in 3rd (or above), but I still posted 0.4sec better 400m time on that run.

always thought that the dragway recorded a terminal speed as you crossed the 400m line, but not sure????

This is just me presuming that they do not measure the speed via a radar-gun, but by tripping over some 'trip lines' which measure the time in between and work out the speed. Though, I'm no expert at this.

Have to say the BOY's blue cars were 2 of the nicest lookin' cars out there. That blue with the body kits and wheels looks friggin' awesome!!!

Yep, they did look great ...I think the wheels make the biggest difference. What size wheels are you guys running? Also, it looked like Yun had the wheels wider appart (and filling in the wheelarches better) ... wheel spacers?

ps. I just remembered that I was running about 28psi (cold) in my tyres and LK was mentioning to me to drop it toa lot less ... what pressures was everyone else running?

frosty

LIONKING (and the lioness)

Must have been hairy changing lanes!

mchapman

iTrader: (1)

Good work guys!

Apart from the fact that the auto doesnt have a clutch to worry about I think the longer gears and lower final drive ratio is helping the auto during launch. Converting wheel spinning torque in the manuals into good take off and the extra rpm they have is helping also.

So whos for a reflash?

lionking

Not a problem. I crossed back and forth all the way down just to make it interesting.

ypwpat

I think this teach us Too much Torque is Useless for Drag race when you have street tires Because your Tires just can't get a Good Grip. Need those Slick Radial Tyres to get the Grip

lionking

[QUOTE]Originally posted by DavidM
always thought that the dragway recorded a terminal speed as you crossed the 400m line, but not sure????

This is just me presuming that they do not measure the speed via a radar-gun, but by tripping over some 'trip lines' which measure the time in between and work out the speed. Though, I'm no expert at this.

I was lookin to see how they measured it at the end. Looked like there was a box at the finish line like the one at the start. Wasn't a lot of time to have a good look though.


ps. I just remembered that I was running about 28psi (cold) in my tyres and LK was mentioning to me to drop it toa lot less ... what pressures was everyone else running?

I was at 25 psi cold on 17" 040's. Was gonna try even less (20) but 25 seemed to work ok for me. I recon less pressure would help to get you closer to your 2 sec 60' time. What about tryin out your r-spec on the back?

DavidM

I recon less pressure would help to get you closer to your 2 sec 60' time.

Yeah, it might help ...maybe I should try 25psi next time I'm there. Out of curiosity I had a look around to see if any other cars have been there recently to see what times they are runniong and I found out that a MY00 WRX was there onthe 24th of September and it runthe best time of 13.7 @ 99mph with a 60ft time of 1.965 (not sure what and if any mods). The 1.9sec 60' time is awesome though, and they are saying that perfect 60' time for a WRX is 1.7 -1.8sec.


What about tryin out your r-spec on the back?

hehe, maybe if they let me do a lap of Calder before I line up ;-) The R-spec tyres are very slippery when cold ... I know that when I leave the pits on my out-lap, that the tyres will spin relativey eazy in 1st gear once you're already moving (ie. at 25 - 30kph). Not sure if they would get sticky enough just by doing a burnout ... though, I have seen a video of a 350Z with R-spec tyres pulling a 13.1sec 400m time in the States.

Though, I'd rather do it with street-tyres as that gives you some kind of reasonable comparision to other cars. If I run the R-spec tyres and managed to run low 13s, that would not really be indicative of what the car can do as anyone else can do that (ie. put on R-spec tyres and cut of 1sec). I like the fact that I can compare the times/data with you guys (and other cars that have been there).

I think this teach us Too much Torque is Useless for Drag race when you have street tires.

This is where the S2000 was good. I still maintain that the S2000 is an easier car to launch of the line as it just needs a lot of revs (ie. ~7000rpm) and then a clutch-drop. Because it has a more rear-biased weight-distribution, and becasue it's tyres have a wider foot-print than on the Zed, it seemed to rocket of the line while with the Zed you feel like there's just not enough rear grip to get the mass moving.

The other option is to have that much torque that you do not have a 'power hole' at low revs and you can just take off from idle (ie. AMG Mercs).

Apart from the fact that the auto doesnt have a clutch to worry about I think the longer gears and lower final drive ratio is helping the auto during launch.

I always though that the auto was better suited for 400m (and 100kph) runs as it has a more 'suitable' gearing and can hold each gear longer. I would love to see what the mags can get out of it, but going by our experience you'd expect 0.2+sec better 400m time than for the manual. I know that HVSs often run better 400m times with auto than manual for similar reasons.

ps. Would be great if the times from the night were published somewhere so that we could look up what all the other cars were running.

ZZZ-35

Just back from working all weekend, I had a ball Friday night even though I was given a beating by LK in this girly car (only the auto shifter part) I think the auto is the weapon of choice at the drags. My best run was my first one 14.4 and with 36psi in the rear's go figure, I drop the pressure down to 22psi and got slower the harder I tried my slowest run was 14.8 but still it was great fun catching up with the guys again, maybe next time I can improve a little more with the added experience of Friday's effort, its harder than it looks with a manual box..

David

DavidM

Hey, what cars did everyone run? I run:
- auto XR6 (non-turbo) - running 15.3
- 350Z Manual - running 14.6
- Commodore (early 90s model) - running 15.9
- '75 Toyota Corolla (or some other Toyota) ... this run 13.5sec pass.

ps. Here's the gearing/speeds for the manual and Auto Zeds as I worked them out before:

Manual 350Z @ 6,600rpm:
- 1st gear = 61.0kph
- 2nd gear = 99.6kph
- 3rd gear = 142.5kph
- 4th gear = 182.1kph
- 5th gear = 231.5kph
- 6th gear = 291.6kph

Auto 350Z @ 7,000rpm:
- 1st gear = 68kph
- 2nd gear = 107kph
- 3rd gear = 165kph
- 4th gear = 243kph
- 5th gear = 306kph

LK, I'm sure that you said that you needed to shift to 4th gear right before the finish line .... is that right? How long did you need the 4th gear for? One would think that you would not need the 4th gear in an auto over 400m as your trap-speed was between 160 and 162kph. All I can think of is that:
a) maybe I'm onto something with the trap-speed printed is an 'average' calculated over some disatance
b) or/and the 25psi pressures in the tyres lowers your possible top speed.

Have you tried crossing the line in 3rd?

lionking

The auto (drive) was shifting into 4th pretty early. Not sure what revs but probably around 6000. In manual mode I held it in 3rd across the line on one run to see if the car would make it. It JUST crossed the line at 7000 rpm and hit the limiter a length or 2 later. I'm guessing on other runs I was shifting anywhere from about 50 metres to as little as 5 metres out.

I ran one of those drag beasts on one run. 11.604 @ 114.64mph

Also had a run with the 240. He must have had a crap run because he said he had been well into the 11's on a previous night. I took the start and didn't see him till he rocketed past me near the finish. 12.954 @ 118.07 mph

KY350

Reaction time is unimportant if you're just trying to post the fastest 1/4 mile time. It's only important at the traffic lights.

Also, next time you go drag racing, hammer the accelerator on the 2nd last orange light as the Xmas tree lights down to green. By the time you realise the 2nd last orange and hit the gas, the light will turn green as you react and you will have a fast reaction time - never wait for the green light before hitting the accelerator.

harryw

Sounds like these Mexicans are having too much fun!

Never really been into drag racing and no it's not because of the stilettos. "Real" racing has corners! Anyway, I'm brave, when is it our turn?

As always

H

DavidM

In manual mode I held it in 3rd across the line on one run to see if the car would make it. It JUST crossed the line at 7000 rpm and hit the limiter a length or 2 later.

Any idea what effect that had on your time and trap-speed? I owuld have thought that your time and trap-speed would be slightly better staying in 3rd.

Reaction time is unimportant if you're just trying to post the fastest 1/4 mile time. It's only important at the traffic lights.

Yes I know, I was just trying to say that LK and his auto would have been much further ahead of me if we lined up at Calder even though there was onlu 0.2sec ET difference ... not only was he quicker across the 400m, but also he could 'react' quicker than me. The auto seemed to have made it easier to react quickly.

Though, I have heard a few people say to go on the orange, so I might try it next time ... still, I'd rather get a better launch (and hence better ET) than reaction time ... like you said - on a time-slip it does not really make a difference.

ps. I was reading the 'drag racing' forum and theres a bit of an argument on tyre pressues. Some people say drop them to ~25psi, while others are saying that they will grip the best at factory settings. I can see a reason for both, but don't know enough about the tyre-dynamics of the tyres that we have to decide which is better.

ypwpat

yep the Auto you don't need about the Clutch lol Just need to hold brakes and Accelerator :P

When start just release the brakes of the car goes Flying :P

Btw do you think the Time can also be effected by the Tires thickness?

I had 19" and LK have 17" I saw all draggers has a Smaller wheels with a Thick tires. what do you think?

Btw why do you think the Reaction time is unimportant? aren't the Time was set to Count when the Light turn green?

KY350

The auto seemed to have made it easier to react quickly.

David - I understand that you were explaining that the "distance" between you and LK would have been significant due to a faster ET and RT by LK - OK
But manual / auto box does not dictate RT - that is dependant on reflexes (and to an extent luck if your going off the orange) as the car only has to roll a few cm over the front staging line to record the RT.

ps. I was reading the 'drag racing' forum and theres a bit of an argument on tyre pressues. Some people say drop them to ~25psi, while others are saying that they will grip the best at factory settings. I can see a reason for both, but don't know enough about the tyre-dynamics of the tyres that we have to decide which is better.

I don't know the theory on tyre pressures, but one thing is for sure - will small drag wheels and high profile tyres, low pressures are the go. So I am not surprised that people traditionally believe that the same should apply for large street wheels combined with low profile tyres - may / may not be true.
Best way to test is to get an AUTO Z ( to minimise the probability of driver error on launch) with street tyres and try varying pressures between 25 and 35 psi. Then compare the ET's for your answer.

I had 19" and LK have 17" I saw all draggers has a Smaller wheels with a Thick tires. what do you think?

I suspect that you are disadvantaging yourself running 19's with very low profile tyres. Again need to test different size wheel / tyre combinations on an AUTO for an answer.

KY350

The auto seemed to have made it easier to react quickly.

David - I understand that you were explaining that the "distance" between you and LK would have been significant due to a faster ET and RT by LK - OK
But manual / auto box does not dictate RT - that is dependant on reflexes (and to an extent luck if your going off the orange) as the car only has to roll a few cm over the front staging line to record the RT.

ps. I was reading the 'drag racing' forum and theres a bit of an argument on tyre pressues. Some people say drop them to ~25psi, while others are saying that they will grip the best at factory settings. I can see a reason for both, but don't know enough about the tyre-dynamics of the tyres that we have to decide which is better.

I don't know the theory on tyre pressures, but one thing is for sure - will small drag wheels and high profile tyres, low pressures are the go. So I am not surprised that people traditionally believe that the same should apply for large street wheels combined with low profile tyres - may / may not be true.
Best way to test is to get an AUTO Z ( to minimise the probability of driver error on launch) with street tyres and try varying pressures between 25 and 35 psi. Then compare the ET's for your answer.

I had 19" and LK have 17" I saw all draggers has a Smaller wheels with a Thick tires. what do you think?

I suspect that you are disadvantaging yourself running 19's with very low profile tyres. Again need to test different size wheel / tyre combinations on an AUTO for an answer.

lionking

Hola H,

Nosotros tenemos un gran tiempo aquí en Melburne en las carreras del obstáculo. Arrepentido usted pierde fuera. Quizá un día que usted puede vivir en una ciudad que es tan gran como Melburne y juego con nosotros. Soy también lookig hacia adelante a obtener en algunos acapara con los chicos pronto.

Tendremos que alcanzar la próxima vez usted es el sur de la frontera. ¡Y recuerda de no decir "faaaark" ni usted entrará el problema!!

Rey de León

ypwpat

wtf are you talking about? English speaking only please

KY350

Go to Melb and join the fun - you must be kidding LK.

Harry - Scathing is going to WSID on Wed evening if your in town. I couldn't get a helmet testerday so I won't make it unfortunately.