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Has anyone done a Top Speed run in their SSEI or GXP? I got my GXP up to 135 before I came up on traffic and it felt like I had more to go!

Just a reminder, be careful what you post. Street racing is strictly prohibited, and posting of dangerous driving is also frowned upon. 135 with traffic around doesnt sound to safe.

top speed can be found based on gear ratios. there are java apps which let you put in the info you need to get a theoretical top speed. of course you have your coefficient of drag. but afaik that doesn't really come into play until your above 150 usually.

150 in my SSEi, on a closed course

95 yea im lame

My PCM stops me at 110...but not for long

150 and my GXP was maxxed out.

156 and I backed out (about 3 years ago on an old closed desert highway in Eastern OR).

My a$$hat tore a piece of leather off my seat when I got out from over-pucker syndrome. I didn't have great tires then. I presume the car is capable of more now (talking about the green care in my signature), but haven't tested it recently. Not much point really.

I lost a wheel weight in the 93 coasting back DOWN through 125, and nearly ditched the car. Think about that next time you're over 100mph.

willwren wrote:156

did it feel stable? I think with the design of the aerodynamics of those cars, they'd be able to attain 170+ given enough space

willwren wrote:(talking about the green care in my signature)

You mean the green supercharged one?

Mine felt good to 140, but the 140-150 was some scary *shoot*. I won't be doing it again.

erics00ls wrote:

willwren wrote:156

did it feel stable? I think with the design of the aerodynamics of those cars, they'd be able to attain 170+ given enough space

Not gonna hit 170 without some serious work. Under car aero needs to be addressed, especially near the bumpers, Bubble butts will be more stable than spoiler'd cars. This isn't even mentioning upper RPM power to push it through the air, especially with only one gear (realistically) to work with.

What does it take? LS2 GTO's will get 175-180mph without a limiter, they're 400HP stock (not over rated mind you) and atleast as slippery. Weight isn't an issue with top speed, only acceleration and handling.

I bounced my 95 SSEi off the limiter a couple times on an old section of US40, so 128 there.
The PA I've only had up to 125, and backed out because I was afraid the hood latch would fail.

fwiw:

most 'normal' car's speedos become HIGHLY inaccurate when measuring speeds above 100mph.

your gearing is what limits your top speed #1
+
how well air 'flows around' your car aka your coefficient of drag #2

not HP/TQ for the most part. it's much smaller factor.

My HUD is within 1mph of my GPS over 140.

Yes, aero drag plays a huge factor the faster you go. Weight of the car and hp/tq/gearing mean less and less the faster you go, and it's a logarithmic function.

I danced around 140mph in the Aurora when I first got it. Haven't maxed out the GTP...won't be able to thanks to deadly harsh Ontario road "racing" laws.

Oh, I know my speedo is WAY off that high. I have taller than stock tires, so I was probably going around 6-10mph faster than the reading.

And BTW, my 95 SSEi felt like it could just keep going faster if that limiter hadn't been there, and if I'd had better rated tires. It got a little light around 95, then at 110, it felt like the car "settled" on the shocks and just sucked down on the road. Absolutely stable and smooth. The PA feels nice and stable, too, but the hood gets to moving at over a hundred, and by 125, was pulling up visibly above the fenders. There must be a massive amount of lift over the hood...

I've done over 100 in the '89 but I hear it tops out around 120-130 for a more or less stock LN3. I don't think I'll ever push it that high though... not with regular street tires/wheels at least.

I've only went as far as the speedo goes, so I guess 128 for stock limiter. Car feels very stable at that speed also, much better than the GP I rode in at that speed, it felt like it was gonna fall apart, and it was a well taken care of car.

I'm a wuss. Only 111mph according to the HUD.