Goal: To go 186+ mph / 300kph in LT1 Coupe

[HOLST]

Hey folks

I´ve had my Corvette for a year now soon, and am very satisfied with the car. It is in a very good condition and has just passed the 80.000km mark (soon 50k miles). Since I live in Norway, I do not drive my car in the wintertime.
Recently I drove a trip to Germany and got to test my car a bit on the famous German Autobahn (some streches of highway without speed limits...), but didn´t get to go as fast as I wanted, mainly because there was a lot of traffic and only two lanes in each directions. Anyway, I got to see 260kph on my speedometer (161,5mph) (my brother took a photo of it), and had to brake rather hard to avoid hitting a another car in the rear.. This was in 5th gear, and I´m not sure how far I was from top speed (maybe not far). The car has a 6 speed manual with the standard 3,45 axle ratio. Maybe it´s slower in 6th. The car has only minor modifications such as a Superchips chip, sports exhaust, K&N air filter, throttle performance swich, bypass tube and so on (probably around 350fwhp). But I´m thinking of installing an ATI Procharger P-1SC supercharger on it, and also other modifications (to get 500+fwhp) which should be enough power.
My question is then simply; is the rest of the car up to the task of my targeted top speed? Can the transmission cope with these speeds? I know most people care mostly about acceleration, but I´m speed crazy, and I didn´t think 260kph was such a big deal (I found it to be very stable). (I aslo happen to think that "300" is a nice, magic, round figure...)
What things do I need to concider to make the car "safely" be capable of such speeds? Any suggestions? I´m hoping for some comments and personal views on this subject even if you don´t have any experience with it.
(Excuse my English, but I´m Norwegian...)

PS: See pic of the speedometer at 260kph below, a bit unclear but readable...

Best regards,
Daniel Holst
Corvette enthusiast, Norway

 

[HOLST]

Hmm.. I see that my pictures didn´t show, but I can email them if anyone wants to see them...

-Daniel Holst

 

[Edmond]

Daniel,

Top speed is achieved in 5th gear. The car doesn't make enough power in 6th gear to go fast.

You can do the heads/cam and exhaust that seems to be the standard in mods. You could also do an increase in displacement.

There are a lot of things that you can do to make the Vette' go faster. It all depends on how much you can spend!:L:L:L

 

[67HEAVEN]

Anyway, I got to see 260kph on my speedometer (161.5mph) (my brother took a photo of it), and had to brake rather hard to avoid hitting another car in the rear.

Hi Daniel,
First -- Welcome to Corvette Action Center.

Second -- Please provide your parents' mailing address so we'll know where to send the cards and flowers after you kill yourself.

 

[Vettelt193]

You should compare your car to the ZR1... they advertised 180MPH for it, so your goal is definitley do-able... especially considering the ZR1 did it with 385 HP.

You need to make sure your suspension is good, tires are good, and brakes are good. The ZR1's have 13inch brakes, your car probably has 12 inch... you may want to upgrade. The suspension is also old (assuming you haven't changed it). which just isn't safe at those speeds.

Also, in my opinion, if you spend any extended time at those speeds with the pro-charger installed, you will probably blow your engine, especially if you are looking to go for the 8 psi setup. I really like ATI and their products, and think the LT1 can handle the setup well... BUT, that is assuming you aren't running wide open throttle for an extended period of time.... going full speed like that really requires your engine to be built up more. slapping a supercharger on it will just make it a time bomb.

 

[HOLST]

I just recalculated my goal and realised that the right mph reading would be 187, not 186 (not that it makes much difference). 187mph x 1,60931 (km per mile) = 300,94 kph...

Edmond, thanks for your reply!
By the way, it´s not like I´m planning on cruisin´ at 187mph, I just want my car to be capable of reaching that speed, if only for a short moment, that´s all. I certainly don´t want to blow my engine, and driving this fast is not something I will do often (because the highest speed limit in Norway is 100kph / 62mph and I´m not often in Germany...). But we do have some "airport runways" that are no longer in use (sometimes used for dragracing), not sure how long they are though. But don´t you think the engine could do that with a Procharger without danger of blowing it?
Also, all my brake parts (discs and the other parts I don´t remember the name of in English), wheel bearings and tires (Goodyear Eagle F1 GS-D2 265/40ZR17 on all four wheels - these tires don´t come any wider) I changed 2 weeks ago (new, unused parts of course, also had some other service work done). (That left a rather big hole in my pockets this month, the total cost here in Norway for parts and labour was about $4K, that was not a very fun bill to pick up, I hope there are no more surprises for a while...)

And 67Heaven, thank you!
Btw. I´m not planning to die in the near future..
And my brother also video taped the trip (including 260kph on the speedo), and I have showed the tape to my dad (not my mother of course), and he didn´t say much about it other than that he thought it wasn´t sensible...

 

[HOLST]

Thanks for your reply, Vettelt193!
That´s the kind of feedback I was hoping for. Yes, I was thinking of the 8 psi setup..

-HOLST-

 

[67HEAVEN]

....I have showed the tape to my dad (not my mother of course), and he didn´t say much about it other than that he thought it wasn´t sensible...

You've got a wise man for a father.