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sounds like same ratios as me.. cept the redline.. 4000rpm @ 160km/h sounds about right.

and i was edging on 7000rpm when i tested it.. was still pullin reasonably well... dont think it wouldve reached 300... maybe 290...

i woulda been doing about 274. ive estimated that our ratios given a higher redline is capable of well over 300km/h

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sounds like same ratios as me.. cept the redline.. 4000rpm @ 160km/h sounds about right.

and i was edging on 7000rpm when i tested it.. was still pullin reasonably well... dont think it wouldve reached 300... maybe 290...

i woulda been doing about 274. ive estimated that our ratios given a higher redline is capable of well over 300km/h

phwoar! so now i can brag to my mates haha.

i want a gtr :D

what are you basing this on? in 5th gear, if the engine is doing 4000rpm at 160kmh, all logic would indicate that at 7000rpm the car will be doing 280kmh. and if you go into the redline, maybe 300kmh (power permitting).

is my speedo or tacho out of whack? im pretty sure in 5th the speeds are approx:

1000rpm - 40kmh

2000rpm - 80kmh

3000rpm - 120kmh

4000rpm - 160kmh

therefore, since its a directly proportional relationship:

5000rpm - 200kmh

6000rpm - 240kmh

7000rpm - 280kmh

im pretty sure my reasoning is correct. and the only thing preventing 280kmh is friction and drag.

hsc physics ftw!

I've got a NA R33 GTS, so the ratios are slightly different... At 100km/h in 5th I'm sitting on 3000RPM. So that means it's RPM/30=KMPH.. so 7000/30=233KMPH

haha what is a squid topic?

Squid = no clue, no idea, I have a fast car/bike therefore I am soooo good!, I bought a fast car/bike so people will love me! LOL :D

Squid name came from the UK referring to bikers/hoons in bikes/ :D cars who think their lack of skill is made up for with a fast machine.

what are you basing this on? in 5th gear, if the engine is doing 4000rpm at 160kmh, all logic would indicate that at 7000rpm the car will be doing 280kmh. and if you go into the redline, maybe 300kmh (power permitting).

is my speedo or tacho out of whack? im pretty sure in 5th the speeds are approx:

1000rpm - 40kmh

2000rpm - 80kmh

3000rpm - 120kmh

4000rpm - 160kmh

therefore, since its a directly proportional relationship:

5000rpm - 200kmh

6000rpm - 240kmh

7000rpm - 280kmh

im pretty sure my reasoning is correct. and the only thing preventing 280kmh is friction and drag.

hsc physics ftw!

as metioned earlier i was doing 180 at 5000 when speed limiter kicked in, unless you have changed the gearbox and/or diff in your car you shouldnt be doing more then 180 at 5000

perhaps the previous own converted the car from auto to manual and left the auto diff in it, that would explain the higher speeds

i am curently in the middle of converting mine to manual with the auto diff, i will be able to check these speeds with this set up when is finished at the end of the week

unless someone who has tried this can support this idea? :)

and sucks to have a n/a box :yes:

It does... although any higher diff ratios would really leave me struggling to accelerate. If anything I'd like a lower ratio again (i.e. higher revving) but with another gear :)) 3000RPM at 100 on the freeway does get a little tedious!

as metioned earlier i was doing 180 at 5000 when speed limiter kicked in, unless you have changed the gearbox and/or diff in your car you shouldnt be doing more then 180 at 5000

perhaps the previous own converted the car from auto to manual and left the auto diff in it, that would explain the higher speeds

thats a very interesting theory. a bit far fetched perhaps, i see no reason why my car would be an auto convert! are there any cosmetic giveaways?

im very interested to hear your results.

Last count with a bit more then 217rwKw i managed 265 and it would not go ANY more, basicaly hit a brick wall, mind you 0-210 kph takes SFA in teh first 4 gears, plug in 5th and it takes hours to do any more.

thats quite impressive. im going for a final tune soon, but we reckon its already got 240rwkw.

wouldnt be surprised, because mine charges through 5th too...

cant imagine what it must be like to have 350rwkw, 200-300 in 5sec ftw!

So lets say your car has the potential to hit 300kmh....Where exactly do you plan on using this kind of speed ?....

past "speeding. no one thinks big of you." billboards. surely people will think big of doing 3 times the legal limit? i couldnt do that with a small doodle.

or perhaps i will take my plates off and go for a run around sydney to make a current affair.

the point of the discussion was so that i dont have to do it. we all know curiosity killed the cat. and we all know that if it wasnt illegal, we would all do top speed runs at 3am.

this way, i can tell commodore drivers i have a 280+kmh car, without having to risk life or licence.

Edited by gt-ahhh!

Well I have to admit I dont really know too much about the workings of Dynos...However wouldnt a Dyno be able to measure something like this ? I know one of my Commodores years ago made 170 at the wheels at 195 kmh....So maybe the dyno could give you the reading...I dont know....Ask a dyno operator

Well I have to admit I dont really know too much about the workings of Dynos...However wouldnt a Dyno be able to measure something like this ? I know one of my Commodores years ago made 170 at the wheels at 195 kmh....So maybe the dyno could give you the reading...I dont know....Ask a dyno operator

thats a very good point, but a dyno cant replicate friction and wind resistance. it would calculate the speed based on revs, same as what i have done.

With stock gear and diff ratios and on 17 inch wheels.

I was bouncing off the rev limit at 7000rpm in 5th and PFC recorded 254kmh.

THANKYOU! finally some evidence haha

well thats brilliant. although slightly disappointing. either my speedo/tacho are out or i have different diff or something.

I think a lot of people who have done 200km/h need to actually go to the track and wind out 5th gear. With 260rwkws my car loves 4th gear. It pulls nicely. From 180 to 220km/h it pulls nicely, but after about 230km/h ? Well the going gets very hard.

It is all about hp at those sorts of speeds as Skylines with their farked up front bars with big opening and intercoolers, combined with their c-pillar screens are not very aerodynamic at all. Back in the Grp A days the Sierra and even the VN Commodore were both more aerodynamic :)

So you need power to push the car through the air when you have grabbed that tall 5th gear. A 350awkw R33 GTR will do 310km/h (Avalon airport and radar gun). Perhaps it could go a bit quicker with more runway....but for isntance at Phillip Island i come onto the straight at 180km/h and only pull 240km/h down the straight. Which is slightly down hill and has a quick turn 1 at around 170km/h. Now compare this to Sandown where you come onto the straight at about 70km/h and the back straight is up hill with a slow 60km/g corner off the back straight....so all that said i still hit 234km/h. So on paper i should be going way quicker down the straight at Phillip Island as i come on to the farking thing 120km/h quicker, is down hill, and longer, and i brake later...yet i go less then 10km/h quicker.

So you can see that once you hit a certain speed you almost crawl up the speedo and have to really fight for 10km/h . So you need plenty of power to be doing 270km/h

I think a lot of people who have done 200km/h need to actually go to the track and wind out 5th gear. With 260rwkws my car loves 4th gear. It pulls nicely. From 180 to 220km/h it pulls nicely, but after about 230km/h ? Well the going gets very hard.

It is all about hp at those sorts of speeds as Skylines with their farked up front bars with big opening and intercoolers, combined with their c-pillar screens are not very aerodynamic at all. Back in the Grp A days the Sierra and even the VN Commodore were both more aerodynamic :ninja:

So you need power to push the car through the air when you have grabbed that tall 5th gear. A 350awkw R33 GTR will do 310km/h (Avalon airport and radar gun). Perhaps it could go a bit quicker with more runway....but for isntance at Phillip Island i come onto the straight at 180km/h and only pull 240km/h down the straight. Which is slightly down hill and has a quick turn 1 at around 170km/h. Now compare this to Sandown where you come onto the straight at about 70km/h and the back straight is up hill with a slow 60km/g corner off the back straight....so all that said i still hit 234km/h. So on paper i should be going way quicker down the straight at Phillip Island as i come on to the farking thing 120km/h quicker, is down hill, and longer, and i brake later...yet i go less then 10km/h quicker.

So you can see that once you hit a certain speed you almost crawl up the speedo and have to really fight for 10km/h . So you need plenty of power to be doing 270km/h

I cant speak for Sierras but i can for VN commodores..There is no way they have any sort of Aero advantage over skylines..if ever there was a brick wall of a car this is it. My last done up VN which made 170 kw at the wheels was a prime example. I once compared it to a mates boosted SR20 180 SX...to ride in both my car would have mauled him 0-80km....80-120 it would have been dead even..but 120 + see ya later 180 SX would be dissapearing into the distance...Even comparing my last Skyline , my R32 GTS4....Not as fast as the VN I had...0-100 it would have been eaten alive by the commodore...but 100+ would have been even up to 130 but after that the Skyline will pull away...Even other Commodores I have been in over the years are the same...they just run into that brick wall at 140kmh...maybe the newer ones have improved Aerodynamics

I cant speak for Sierras but i can for VN commodores..There is no way they have any sort of Aero advantage over skylines..if ever there was a brick wall of a car this is it. My last done up VN which made 170 kw at the wheels was a prime example. I once compared it to a mates boosted SR20 180 SX...to ride in both my car would have mauled him 0-80km....80-120 it would have been dead even..but 120 + see ya later 180 SX would be dissapearing into the distance...Even comparing my last Skyline , my R32 GTS4....Not as fast as the VN I had...0-100 it would have been eaten alive by the commodore...but 100+ would have been even up to 130 but after that the Skyline will pull away...Even other Commodores I have been in over the years are the same...they just run into that brick wall at 140kmh...maybe the newer ones have improved Aerodynamics

Maybe your VN with 170kws... but its a fact that the VN Grp A had less drag then the R32 GTR. It was well publicised in the racing world in the era of Group A racing. What that means with downforce etc etc who knows, but the coefficient of drag was lower for the Holden VN SS Group A then it was for the R32 GTR. The Cd for the R32 was something like 0.40, where the VN was 0.34...and the new R35 i read is somehting like 0.27

I can't wait to get on a strip and see where mine tops out.. twincam 30, 25box, 3.9 diff ratio, it powers through 5th without breaking a sweat! I don't see it being that much different with the taller diff, I'm doing ~2900rpm in 5th @ 100kmh.

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