GT-R

[Kent Townley]

As drag increases there is a cube relationship to the power required to overcome that drag. As the curve becomes more vertical the required HP to overcome drag becomes infinite. Its been years since I took a physics class but I think that's close?

You have the cubic relation correct.

V^3 = HP/k, where k=(drag coef * density of air)

However, from this equation we can see that as HP increases, then velocity will increase. Obviously there are practical limits to the amount of HP that can be applied. But the limits to velocity are not because of the aerodynamics of the vehicle.

 

[Larry L.]

But of course. My bad… misinterpreted your initial comment.

No 'biggie' 'far as I'm concerned, sir! :thumbsup:

 

[Larry L.]

Could you explain that? Are you thinking about stability rather than drag?

Well, now that you mention it - BOTH! :shocked:

Initially I was only thinking about the 'brick wall' aspect...:sick:

 

[John Ross]

John, Are you thinking about adding a GTR to your stable?

I'm ALWAYS thinking, Dean... ;-)

JR

 

[John Ross]

Hi John-When I ordered my GT_R #7 I was going to use a tunnel port 427 FE block that I have and Fran said it was no problem-That being said I would think you would not have an issue. I have since changed to a blown coyote.

The 385 is bigger than the FE block. That said, I don't think there'd be a problem.

Ford 385 engine - Wikipedia, the free encyclopedia

JR

 

[Roger]

As drag increases there is a cube relationship to the power required to overcome that drag. As the curve becomes more vertical the required HP to overcome drag becomes infinite. Its been years since I took a physics class but I think that's close?

You are correct that the aerodynamic drag increases as the cube of the speed. At some point the required power becomes uneconomical, but that doesn't stop everyone.

To increase the top speed by another 10% will always take a 33.1% increase in power (nothing else changed). There's nothing that I'd call a solid brick wall, not before hitting supersonic flow anyway. Other issues, like gearing, tyres and stability are more limiting IMO.

If you could get 200mph with 500hp, then you get 250 ish with 1000hp (ignoring mechanical losses). 1200hp sees nearly 270mph. 300mpg would take ~1700hp.

How fast do you want to go?

 

[Mike]

I'm pretty good at 150mph... as long as I can get there quickly

 

[Luke S]

Couldn't we get a pretty good idea of drag by looking at what the original Robertson cars did? In a restricted class, someone should be able to get a realistic hp figure. And then see if the top speed at Daytona or Lemans can be located. Calculate from there as from everything Fran has alluded to is these cars will be quite similar.

Are we expecting them to be less aero than a production GT? Did the race cars take liberal design in the drag/downforce equation? Production based GT's have gone over 270 in the mile with much more weight than a CF Fran special.

 

[Mike]

Wouldn't most track cars with downforce have a lower top speed than a street version without the additional downforce like the GT-R vs the FGT? Doubt there are many road courses where one needs to exceed 200mph?

 

[Glenn M]

If you could get 200mph with 500hp, then you get 250 ish with 1000hp (ignoring mechanical losses). 1200hp sees nearly 270mph. 300mpg would take ~1700hp.

Hey Roger,

If you know the secret to getting 300mpg along with 1700hp I'll have one of those please! You should be making a fortune!! :lol: :lol:

Glenn

 

[Justin]

Wouldn't most track cars with downforce have a lower top speed than a street version without the additional downforce like the GT-R vs the FGT? Doubt there are many road courses where one needs to exceed 200mph?

Exactly. Some of the fastest track cars I've ever seen were the Viper ACRs. They only top out around 175, have 600+ hp, make a ton of down force at speed, and lay down times just shy of a Radical out here in Pahrump (Spring Mountain).

Unless you're competing in the Texas Mile, I don't understand the reasoning of having a trans that will bet you more than 200mph (not including a "highway cruising" gear).

 

[Roger]

If you know the secret to getting 300mpg along with 1700hp I'll have one of those please! You should be making a fortune!! :lol: :lol:

I'm not a fan of speed - I much prefer acceleration (in all directions). That's also more important than top speed on a race track.

As for the new Ford GT, it would seem quite difficult to get major power increases from it, as it's already doing quite well on power per litre. I do like the kick that you get when a turbo hits its stride though, and the sound.

 

[Matt K]

Exactly. Some of the fastest track cars I've ever seen were the Viper ACRs. They only top out around 175, have 600+ hp, make a ton of down force at speed, and lay down times just shy of a Radical out here in Pahrump (Spring Mountain).

Unless you're competing in the Texas Mile, I don't understand the reasoning of having a trans that will bet you more than 200mph (not including a "highway cruising" gear).

I'm not in the market for a GTR yet. If I was, however, I'd strongly consider doing a mile capable car, and that's the only reason I brought up the trans. A sc or tt build with multiple maps/boost levels could still function on the track and be a killer mile car.

 

[Bill]

I watched the premier of "How It's Made: Dream Cars - Superformance GT40" on the Science Channel last night. There was a lot of new video content on the HiTech factory down in South Africa...Check it out

 

[Mike]

Exactly. Some of the fastest track cars I've ever seen were the Viper ACRs. They only top out around 175, have 600+ hp, make a ton of down force at speed, and lay down times just shy of a Radical out here in Pahrump (Spring Mountain).

I'd rather have sticky than long legged. Now as I repeat that I think I like sticky and long legged! ha

 

[Justin]

So Fran... Any updates for us?

 

[Luke S]

Fran,

Come on, give us a Valentines treat. How about an update on progress of kits in production or something to keep our anticipation in check 3 Mos since last official update as we play with ideas/pics of what Ford's doing next in this arena.

For the rest of us that follow this thread:
Who's going to build the first V6TT? Ford has released the controller now if OEM ECU important.

 

[Dean Lampe]

Is that engine available as a crate engine?

 

[Ed Johnson]

I second Lukes request--Fran we need a progress report!! Please

 

[Justin]

Is that engine available as a crate engine?

The normal 2.0 and 3.5 ecoboosts are available, but I doubt they'll offer the 600hp version from the new GT.

 

[Scott Davis]

Get comfortable....I've been waiting for details on the apex since June 2013. lol Though I'm sure details on the GTR will arrive before the apex.

I also doubt they will offer that 3.5tt as a crate offering. That engine probably has very little in common with the stock ecoboost other then the block and maybe unported head. Anything rotating is certainly lighter/stronger/much more expensive.

more like this
https://www.youtube.com/watch?v=kbQqF45y-3g