Query: V35 Top Speed

[rip]

hey fellas if someone can help me with the Question.

What is the top speed for the speedo dial of the skyline V35? Is this the top speed it actually does?

[MaXiMuS007]

Japanese cars are electronically limited to 180km/h - this is why they all have 180km/h speedos.

You can get speed cut defenders which will remove the limit.

Anyone know how fast it would go without the limiter? My guess is 240-250ish (it does have a low Cd)

Edited May 28, 2008 by MaXiMuS007

[mellowman]

my mate the other day in his 350z hit 230km and it wanted to keep going so perhaps around 250 maybe more...

has anyone tried to take their v35 over 180?? does it speed limit and loose power?? what happens

[prdreilly]

my mate the other day in his 350z hit 230km and it wanted to keep going so perhaps around 250 maybe more...

has anyone tried to take their v35 over 180?? does it speed limit and loose power?? what happens

I found that it went about 8 Km/h off the end of the dail, before it hit "the wall". Nothing dramatic, still smooth, just stops accellerating.

[MaXiMuS007]

That just means your speedo is 8km/h off!

I had a quick search on the net, some G35 drivers reckon they have seen 160mph (256km/h) in a 6MT

[NISMO]

On the track, the car gets to 180 quite easily and I would guess it's got a lot more in it. From memory it was around the 4500-5000rpm range in 5th gear. I've done a cruising lap where it was in 6th sitting at just over 3000rpm doing 160-170km/h

[spikey]

my mate the other day in his 350z hit 230km and it wanted to keep going so perhaps around 250 maybe more...

has anyone tried to take their v35 over 180?? does it speed limit and loose power?? what happens

I've done twice top speed on my v35, it's speed limit. u will feel the power banned even you hit the pedal.

[scathing]

Non-JDM 350Zs have a 250km/hr speed cut. I've hit 243 (speedo indicated) before, and that was a struggle to reach even though I was near peak torque.

Theoretical top speed is around 300km/hr with a 6MT, if you crunch the numbers and calculate with a 6850RPM fuel cut. There's no way a NA FM platform car is going to reach it though.

[MaXiMuS007]

Interesting, scathing.

How do you do the theoretical speed calcs?

[rb26stagea]

look at the gear ratio for 6th gear (in a manual), and cross reference it with the known rev cut in the car: it will give you the theoretical top speed, ignoring friction, wind resistance, etc...

[MaXiMuS007]

Gotcha...

Engine Speed to Speed of Car:

v = 2πrω/Ggk

where:

v=velocity (m/s)

r= radius of tire (m)

ω= engine speed in rotations/sec

G= final drive ratio

gk = k-th gear ratio

Assuming 6MT with 18" wheels & stock tyres, theoretical top speed = 300.1264km/h!

[MaXiMuS007]

I've spent far too much time this afternoon trying to develop a spreadsheet to do the top speed calcs. The calcs are based on a 6MT on 18s and the spoiler (Cd=0.28).

I can't find any firm data on the frontal area of the vehicle, so I have assumed Ap=2.5m^2.

The theoretical maximum speed is ~308km/h based on the peak power figure alone. Obviously this will be limited by gearing and air resistance.

The maximum real speed I calculate is 281.02km/h... this corresponds to 6150rpm in 6th gear. Air density is assumed as 1.204 @ 20degC.

FYI, if the frontal area is actually 2.8m^2, maximum speed reduces to 269.65km/h.

Lower temperatures (higher air density) will also affect these figures.

[scathing]

I was considering putting a 3.9 final drive in my diff, so I had a look at how it would affect my in-gear speeds.

This table provides the data, although it does need to be updated for the HR engines' cutout and the possibility that some FI guys might want to run the 3.2 final drive out of the auto diff to make more use of their wide spread of torque. I know, if I was going TT, I would.

[matt smith]

I have a gt-8 and have done a couple of runs recently to test exactly that for my own curiosity.It certainly wasn't limited at 180 and still had heaps left at 210,but ran out of road.i will say it gets there in no time as well.

[MaXiMuS007]

If anyone is interested, I've attached my top speed calculation spreadsheet. Defaults numbers belong to a 2003 6MT 350GT. Spent WAAAAY too much time on it.

Feel free to play around with it as you wish. It should work for any vehicle (with a maximum engine RPM of 8600)

Speed_Calcs.zip