toddk911

I found an old European Car issue that did the "Breaking 200 mph" test with 3 Powerhaus cars and the new, at the time, 993 twin turbo. This was the first time I read about with Powerhaus. They had David Rain's (Powerhaus owner) 944 turbo with, at the time, 336 rwhp at 1.1 bar and two other 911 turbos all with just under 400 rwhp. I was surprised that the 993 TT factory claimed 400 hp/tq at the flywheel was actually at the wheels. It had 397 rwhp and 436 rwtq, BONE STOCK!! That explains it's performance numbers a little better.

The 951 hit 175 then they pulled back. Said it would have hit about 180 and would need 125 more hp to hit 200.


The 930 hit 168. It was Todd Zucconne's, the Powerhaus service engineer.

The 911 American roadster, with top down hit 178!!! That must feel like flying in a plane but with your head out the window.

The 993 TT hit 192. They estimate 70 more hp!!!! to hit 200.

That terminal velocity is a bitch.

TonyG

The 951 would have also needed much different gearing to hit 200MPH.

It doesn't have anywhere near enough gear to do it stock with the factory gearing.

streckfu's

Taller gearing or or raise the rev limiter. Danno posted before that the stock gearing needs 7300 rpms to hit 200.
Ouch.

Anyway you can post that article???

Jeremy Himsel

IIRC, Dfastest951 claims 195ish in his 951. I believe he's using a 968 trans. I could be wrong.

toddk911

Ok, I will try to get my neighbor to scan it.

There were numerous other mods to the 951, so might not have been stock gearing, but I believe the 7200 rpm figure to achieve 200 was with less hp.

They said when they pulled out at 175, they were only at 6000rpm and it was still pulling strong.

TonyG

It ain't gonna happen... not with stock gearing.

I would also question the aerodynamic stability of the 944 body at that speed.

With US spec 951 gearing (the ROW is shorter gearing, so that wouldn't help, only hurt top speed), 17" 255/40 tire, you would require over 7500 rpms in 5th hear to break 200mph.

Considering that 99.9% of all "built" 944 turbos don't make their HP peak above 7000rpms, 200MPH is pretty much out of the question.


Also, with US spec 968 gearing it ain't gonna happen either. Not even close. The same tire combo with the 968 transmission would require over 7900 rpms to do it (break 200mph).


175mph with a US spec gear, and the same tire combo, would require 6600rpms.




I'm not even addressing the HP requirements... yet.

ian

Tony G,

Email me please, I have emailed you a couple times and would like a responce. Or tell me what I want to hear on this board, thats fine by me, but by all means get back to me. Please....

email ian_klass@hotmail.com

MachSchnell

If you think 178mph in the Am Roadster is scary, imagine nearly 200 in a diablo VT roadster!

toddk911

"175mph with a US spec gear, and the same tire combo, would require 6600rpms. " I am pretty sure the magizine article was not wrong as they state 6000rpm.

Are you not taking into account hp???? Just to use a wild example, I don't care what the stock gearing is, with enough hp you WILL hit 200.

ninefiveone

It's very much about the gearing, is it not?

I've been seeing this alot on the boards recently. People doing a chip upgrade and then saying they see higher speeds at the top of 3rd gear or somesuch. It just can't be. More hp may get you to 6500rpm quicker but you won't see a higher speed than you did before. More hp does not change your gear ratios.

Yes, with enough HP you will hit 200mph but not if the hp doesn't come at the right place. 1000hp at 2500 rpm will get you the same speed as 200hp at 2500 rpm. You need more hp to get TO the RPM's needed for 200mph but that doens't change what rpm's the motor must turn to be AT 200mph.

Jeremy Himsel

HP has a lot to do with it. If it was all gearing the S cars and 89's would have the same top speed as my non-S. Our cars were drag limited not gear limited in the 150ish top speed. I believe the non s cars were 152 and the s cars were 160? Don't quote me on the exact top speeds. I will agree that HP in the right place has a lot to do with it. A Car that has 1000 HP @ 2500 and 250 HP @ 6500 won't make your top speed any better than 250HP car.

TonyG

Actually, HP, at this stage of the argument has nothing to do with it. I don't care if he has 5 HP or 5000 HP. The engine has to be able to pull the rpms to attain a specific mph. There are no two ways about it.

And I'm 100% correct that if that 951 had a 255/40/17" rear tire, was running a US spec 951 transmission, that 175mph requires 6600 rpms in 5th gear.

And that same example in the above paragraph, would require the engine to spin over 7500rpms in 5th gear to break 200mph.


The HP required to get the car to a given rpm in a given gear is a different argument altogether.

reno928s

I had an 87 944 turbo with the k27/6 housing and some other things done to the motor. I raced it in 98 at the Silver State Classic, in Neveda. I was radared at 168, the car still had some pull but no more RPM's left I had just begun to hit the beginning of red line then I pulled back. My speedometer said I was doing 176 mph, I was sure that I broke the 170 mph barrier but the radar said otherwise. Reno

TonyG

reno928s

Also remember that your factory tach is not accurate either. I've yet to see one that is. They are typically off by about 200 rpms.

I know all of my 951's and my 968 are the same with respect to not being accurate.

streckfu's

Horsepower and gearing are independant of each other. Gears are torque multipliers. Period.