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Discussion Starter #1
I'd be very interested to know what difference you find between 550bhp cars and those around 600 bhp...

It doesn't sound like a very big power increase (ie circa 10%), but I guess it must be if people spend the extra and risk reliability and spend yet more. (N1 Block or RB28? Uprated Gear Set/sequential box, even bigger turbos etc)

I've never driven a GTR (or any car) with more power than about 550 bhp so I don't know myself but I'd of thought for Track work money would be better spent on brake/suspension setup and maybe some weight saving than 10% extra power.

That said Henrys 614bhp looks excellent particularly since the turbos are such good value :)

Does 600 bhp mean you can hit the illusive (except for gary ;)) 200mph in a sensible amount of time?

Cheers,
Jon
 

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Discussion Starter #4
I don't think there are any genuine 1000bhp skylines in this country, and personally I'd like a car which isn't too OTT for road use, though I know some of the 1000bhp jap cars are used daily...

While I could afford to get a 550bhp skyline, and possibly a 600bhp one if its just a matter of bigger turbos/injectors compared with a 550bhp... But if its a case of new block and gearbox then I can't really justify that.

600bhp sounds like the point where things tend to break. David Yu's Godzilla used to be off the road loads and gary's car has broken 2 HKS triple plate clutches :confused:
 

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We'll have to wait

and see.

As Ronnies and Ruperts as well as Henrys and Garys are over 600 then time will tell. Willl have to watch them closely as I've been doing over the past year ;) .

Speculating can be a dodgy thing :eek: .

glen
 

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All good things come to those

that wait.

I ain't rushin in or mouthin off as I've seen whats happened to you :D .

I'll be there soooooooonish :rolleyes: .

glen

ps. Tried cloves have you
 

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200 mph +

the following is just my opinion....

In order to get a skyline past 200mph you must increase the rev limit. I think Guy posted a formula up here a year or so ago with the maximum top speed (theoretically) using std wheels, normal size tyres and a standard gearbox/ Diff gear ratios and at 8200 rpm (rev limiter) the car theoretically would be travelling at 192 mph. now there are several factors here that make this a very difficult thing to prove.

how much power do you need to get to 8200 rpm in fifth without running out of road ?
if you change the wheels (bigger) the theoretical speed should be over 192mph.

I am not sure if this calculation takes drag into account...

but as you can see 192 mph is not near 200 + so in order to get the car to over 200 you need more revs, raising the rev limit to say 9500 rpm would see you past 200 with the standard drivetrain but in order to make an engine strong enough to take the extra rpm's you will spend a hell of a lot of money.

simply changing turbos cams and injectors will give you a much improved acceleration but there will be no protection from the risks of high rpm's.

After talking to Gary who has driven his car at these speeds I am not sure I fancy it much, apparently the car gets incredibly twitchy and the back end steps all over the place as the HICASS gets confused. I have experienced this at 120mph and I nearly shat myself let alone 80mph faster !!

good luck in your speed quest..

/Steve
 

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Rupert's Monologue...

Yes - You have opened a whole can of worms…

Several issues:

1) 1000bhp Skylines: This is an issue that has been discussed again and again on this board so I'm not going to drag it out here. Yes there are some Skylines at around the 1000bhp mark, but they are dragsters and need to be rebuilt just about after every single run. In Japan, there are horsepower completions where persons build their Skyline simply for one Dyno run. They run very high-octane fuels and invariably go pop during or shortly after the run. You cannot use these cars for track days etc, they are simply there to provide a means to bet money. The maximum you can really get out of a Skyline to allow you to run the car for say 5000 miles between rebuilds is about 700bhp.

2) Difference between 550bhp and 680bhp: There is a dramatic difference. I am fortunate enough to have a car that can produce the two separate power figures at the touch of a button (high & low boost settings) and when high is engaged from pottering around in low, it's like you just ignited reheat. It's not just the power that is increased, the torque also increases dramatically and creates lots of unexpected phenomenon like torque steer. You do need the extra power to break 200mph, it simply can't climb the higher revs when running low boost and gets stuck at around 185mph. You do need an upgraded block and running gear to run high bhp. It ate through my original gearbox and blew my block apart in its first incarnation.

3) Top Speed: There is a piece of software that does calculate your top speed and sometime ago, someone was providing a top speed calculation service on this site. Perhaps post a thread asking for this service again. Quick calculation for my car that I can remember:
18inch wheels, standard sized diff, R33 5th gear, 8500 rev limiter = 219mph

Nuff said…

Rupert
 

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HICAS

hmmm, worrying that the HICAS gets confused at 120 I have done that on the motorway (not in this country of course)
 

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Hi Matt,

Don't get too concerned mate, I had a dodgy tracking rod on the n/s rear wheel... fixed now.

I also noticed it when I was driving home from the banzai day with flat tyres, forgot to pump them back up after doing the 1/4 mile times..... DOH.
 

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phew!

So what your saying is if I actually keep my car in good knick I won't have a problem;)
 

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no.

My car is in good nick but things wear out !!

I was in a tight car park and I curbed the rear wheel which compressed the rear track rod, this provided about half of a millimetre of play on the rear wheel, enough to seriously confuse the HICASS computer at high speed. exactly 120mph the tail would give a shimmy which was quite violent, I also noticed it a higher speeds but I bottled it before I looked how fast... having rectified the fault it became apparent that it was happening a lower speeds also but it a lot less severe..

Apparently this fault used to appear on 300zx's a lot especially if they were driven hard, My mates told me not to come out of roundabouts so quickly.. you can expect to be looking into rear track rods at about 40,000 miles if the car is driven hard, mine hasn't even done 20 K yet so I have put it down to the curbing in the car park,which is the only time I know that it has been curbed.
it wasn't even that hard either.....something to bear in mind next time you are in a multi storey car park..

that is the last time I take my car in the north county mall car park !!:D

have fun..
 

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Nasty..

Only joking about the good nick thing.

It is definately something to keep in mind though as it does sound like a weakness in the car. Luckily not many of those though!
 

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I have video with some tuned Jap cars and there is Mr Nagatas 1000bhp R33 which he did 205mph in.

The shot shows so many views and start offs, but basically it struggles for grip in 1st, quickly to 2nd and 3rd in fourth for a few secs and then 5th and then 6th.

He claims 0-200 in around 23secs i think, now i know this guy is known for being a nutter worldwide and he certainly is doing 200+ in a tunnel in Japan.

Anyone seen this clip, i believe Ish has the clip on his website. Not sure what mods it was running, but had gagues everywhere and the speed was indicated on a LCD panel with water temp and engine pressure also being displayed.

Anyway back to the plot, it was very impressive watching that and he sparks up a fag afterward and his hand wasn't even shaking, big nuts for sure for such a little guy!:smokin:
 

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Back on the subject of top speed:

If you lowered the 5th gear ratio and gave the car more power (so the car would still pull rather than loose revs) am I right in thinking you could leave the rev limit alone and gain more top speed (but far less acceleration in 5th)?
 

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top speed runs!

while you have hit on the subject, if anyone wants to try it, elvington airfield is open for timed top speed runs on thursday 25th april and also thursday 30th may. (if date is right, should be last thurs in may)
cost is £70 a car, including grub! its open to anyone on the day, i'm not personally running these two, but the timing gear is proven, and will be set at a suitable distance down the 2.5mile runway!
its flat and clear all the way. i will be going up, hopefully a few other people will fancy a run to see what their cars does (genuine) as opposed to claimed.
i would expect the timing gear to be set at around 1.5 to 1.75 miles distance at least, allowing for some serious speed.

top speed runs will be single car at a time.
spectators are fine, i will check on passenger ride situation of enough interest?
email me direct if you wish
rgds
chris m
[email protected]
 

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intervals

Hi,
Rupert whilst I take your point of veiw, I think your estimation regarding the break down milage of 5000 is a little bit conservative for this power level in road use trim with nice oils etc you should be able to achive 28000 mls on a rebuilt motor, hard driving as I did and hopefully more can be achived with a better block,the only 2 things that actually wore, were the valve guides and the small end bearings, just thought you might be interested
regards
Gary
 
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