porshhhh951

yeah I wish he was still around his car was sick. So he turned about 6800 rpm's at 190?

His car also made crazy tq I am sure. 20-120mph with that much tq must come really really fast. Not to mention smoke the tires

SimonK

That turbo hand should read 2 bars!

SimonK

I will share some wisdom... imho...

BHP = higher top speed, as our stock cars hit a wall due to air resistance and boost roll off - they run out of breath.

However the ultimate limiting factor on a turbo S is 5th gear. The ratio tops up at 179mph - see your car manual trans. diagram section.

So dfastest 195mph (if on stock 5th gear) is bull...

As far as accuracy of our speedos goes, just look at the rpm and draw a line on the trans. in the car manual and you will get true speed.

My speedo is about spot on.

I just got done with the police laser gun 2 weeks ago and at 70mph it was spot on to.

Matt H

I never said there was NO 951 able to do 180. I am saying that a car with a set of chips and 300HP aint getting there.

At any rate there are programs that allow you to test all of these variables and more.
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porshhhh951

Simonk dfast had like 500.

More over rage does has gps and he has gone almost 190 in his car(480whp)

RPG951S

Sorry to disagree Matt, (I wrote this in a previous post) but a couple of years ago, my local PCA chapter (Rennsport Region) had a day of fun at the local PMG high speed proving grounds (an auto manufacturer high-speed testing track here in Quebec).

An [otherwise completely stock] 89 turbo with Autothority chips did something in the neighbourhood of 290+kph/179mph+ (avg of two timed runs). This is using multiple calibrated radar guns and professional timing equipment(NOT the stock gauge!)

I can't remember the exact speed (but I can ask someone who was there that day).

Kesepton

arnt these cars fun? what other veichal can you talk about made 16 years ago arguing top speeds in 190? i mean, no one even contests to the top speed of around 170, its the 190 mark we are shootin for. crazy.

streckfu's

Not true. Speed is determined by gearing at a given RPM. If you raise the rev limiter (or remove it) and you have the power to push the car, you can accelerate until the engine blows.

I set this up for my tires(255/40ZR17) and a 7350 redline. It comes up with a 188mph top speed. Take a few off for drag...

Matt H

Raagi, I will believe that when I see it and not a second before.

For reference a 290HP NSX-T (2003) with a lower Cd and lower curb weight has a top speed of 280 km/h (a touch over 170). It has less frontal area, etc.

Therefore, the 190mph car was either
1) not remotely close to stock
2) the machinery used to test it was just plain wrong
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streckfu's

What are the gear ratios for that car? That has more to do with it that cd or frontal area....

Matt H

NSX
1st 3.066:1
2nd 1.956:1
3rd 1.428:1
4th 1.125:1
5th 0.914:1
6th 0.717:1
Reverse 3.186:1
Final drive ratio 4.062:1

951
1st 3.500:1
2nd 2.058:1
3rd 1.400:1
4th 1.034:1
5th .8286:1
Reverse 3.500:1
Final Drive 3.375:1
Final Drive of 951S is 3.38X:1

So, the 951 has lower gearing which could produce more top speed. However, the NSX has a redline of 8000RPM. Lower Cd, lower body weight, etc.

In a theoritical world if the gearing were low enough you should be able to accelerate ad infinitum. However, we are dealing with real world, where drag matters, contact patch of tires matters, wind speed matters, and lastly HP matters. Putting all of that aside, the wind resistance on a car traveling 180MPH is extreme and the power needed to hit 190 from 180 would be more than a few HP.

I have not to this point said that you could not hit 190. I HAVE said, that a stock car will not come close to it. I also find it incredibly difficult, if not impossible, to believe that a car with just a set of chips did it. I also didnt say it wasnt possible, I said that I would have to see it with my own two eyes.
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Red1

I had hoped to have something to contribute to this thread after last weekend, but (as always, it seems), things didn't work out the way I'd hoped.

My clutch (original, 150K) decided it didn't have the grip for high speed passes, so we only managed 137 mph at the standing mile. Not nearly what I'd hoped for, but still impressed some of my friends since they knew how bad my clutch was slipping.

FWIW, we were at a sanctioned event, private property, no moms-in-minivans cross traffic, etc.

streckfu's

Matt,
I agree that a stock or chipped car will not reach 190. However, with enough power, I think it can get there with the stock gearing (as long asthe engine holds together).......

porshhhh951

I never said it could be done easily. All I am saying is that with enough power you can get to those speeds. People have done it. Hopefully I will do it someday.

Red 1 any word on that N/A 944 that supposedly did 203mph? lol. Just curious. It's possible with a big v8 and nitrous with some serious gearing......but, to do that in a standing mile in a 944(small community) and for us not to know anything about it? ehh....all signs point to someone mis reading something somewhere.

I was really hoping you guy's would find the car and get the scoop on it. It would be by far the fastest 944 in the US at least(ofcourse if it exists)

Anyways it sounded very interesting and was just hoping you guy's found out something.

SimonK

Not so...

Ever been on a bicycle? Pushing the pedals with all the power in the world will not help you spin that final gear faster you will just break it! The gear can only spin that fast for its given diameter. So the final gearing of our cars is the final limiting factor of top speed. Porsche made it relatively tall as they thought 160mph is enough and acceleration was priority.

Yes you can raise the rpm's but the engine simply physically won't be able to spin the final gear faster (not to mention it will blow itself to bits as pistons will not be able to cope) – it will push it stronger though – (torque value goes up – acceleration increases) but eventually putting “700”bhp on it (for example) will brake it to bits.

You can however make the final gear ratio lower but then the trade off is acceleration as engine is labouring harder.

Any 951 therefore knocking on 190mph should go straight in the Guinness book of records.