Worlds Fastest 7

[Kitcat]

Ian7:

 

My "135" hp Crossflow (wh/measured 93 hp at the rear wheels on a chassis dyno) tops out at 108 mph, per my GPS. I run full windscreen and clams.

 

Since it felt like 208 mph, I can not imagine what the 176 mph, etc., vehicles described above must be like.

 

I do know that at a recent track day at Nelson's Ledges, my car wasn't all that much slower than a Caterham 260 that was running there, proving that top-speed isn't everything. Also, I was running faster laps than my friend in his BWW, tho he was hitting 125 mph at the fastest part of the track, where I was at 95 mph.

 

Mike

[manik]

I think you will find more cubic inches is the only way to get a Seven up and above the huge airflow drag that seems to stop most at about 125MPH. That, or make a really aerodynamic, hardtop-enabled Seven (which really wouldn't be much of a Seven at that point IMHO). I suppose you could remove the windshield and opt for an Aeroscreen.

 

I think Kevin's car will need to be not only fast, but really quick to make a record at the Texas Mile. You don't have a lot of room for error down there! Too bad you missed Speed Week at Bonneville.

 

 

tm

[Arya Ebrahimi]

I wonder what Frankn7 would do with some proper aero bits attached. Hmmm....I think this is where Mazda chimes in telling me to get my own car

 

Too bad he's in Australia and I have his car. Muahahahahahaha

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

J/K

[7evin]

manik, we would love to do Bonneville. Our big concern is having to tear the car completely down after to get rid of the salt. I have talked to a few guys who do it

and they highly recommended a complete tear down afterwards.

 

 

I wonder what Frankn7 would do with some proper aero bits attached. Hmmm....I think this is where Mazda chimes in telling me to get my own car

 

Too bad he's in Australia and I have his car. Muahahahahahaha

 

 

J/K

 

 

At a minimum you should do some photoshop work and post it just in case he checks.

 

Might be fun.... to let him squirm a bit down under....

 

Cheers

7evin

[Z3 Stalker]

I believe Dennis Brunton hit 153 mph at Mid Ohio in his Stalker.

[Ian7]

 

My "135" hp Crossflow (wh/measured 93 hp at the rear wheels on a chassis dyno) tops out at 108 mph, per my GPS. I run full windscreen and clams.

 

 

Thx kitcat.

Do you find the 93-at-the-wheels surprising? That's about a 30% transmission loss (!?), or an optimistic 135. Curious.

I have a dyno day in mind for the spring. Hope I remember to post results.

 

Cheers

[Kitcat]

Yes, I was surprised tho not shocked. The dyno "grand prix" can be misleading. Maybe it was the dyno. Maybe Caterham exaggerates the power of its engines (No!). Maybe a little of both?

 

What was useful was it allowed a safer tune to be used (I was running dangerously lean).

 

The bottom line is the engine runs strong and sounds fabulous. And combined with the weight and handling, provides a very balanced package that is tons of fun to drive on the street and the track.

[11Budlite]

7evin,

 

Another post on blatchat with a good discussion on top speed. Specifically, if 200 mph is possible: http://www.blatchat.com/t.asp?id=155703&pn=3&ps=15&c=

 

If you go to page 3 of the thread and look for a post by AdamHay, he has a 10-item list that looks to have some good ideas in it. I would think that anything that you can do aerodynamically would give you the best bang for the buck. You seem to have a good handle on the horsepower requirement. They even mention the 100mpg Caterham that I had posted before: http://www.usa7s.com/aspnetforum/Default.aspx?g=posts&t=2444

 

Here's a photo:

 

http://www.usa7s.com/aspnetforum/upload/475014114_1006214696_1_jul26_mpg_1.jpg

 

"We would like to see the 7s title be held here in the USA7s group." - I agree Kevin, I hope you do it!

 

Bruce :7drive:

[DeanG]

In reference to the blatchat post by AdamHay

 

1. Longer nose with smaller air intake

2. Faired in skinny front wheels with integrated fenders

3. No screen/mirrors/lights, a rigid driver's half door and a hard passenger tonneau

4. No cage, just a small hoop behind the driver's head

5. Skinnyish rear wheels and spats with bolt on side pods to cleave the air past the rear wings (which would have holes or louvres in the back of them).

6. Rigid boot cover with a spoiler extending over the rear to reduce turbulence

7. A rear diffuser to aid air flow under the car (works with the extended boot cover)

8. Fully panelled underbelly

9. Inboard front suspension (not much gain)

10. Aero wishbones (even less gain)

 

I had expected to see a diffuser or two at the 50th anniversary at the dragon. It seems like a natural to me given that the Lotus Seven series 1 had a full belly pan and how some Se7en owners like to experiment.

 

[kitmfgr]

Kevin, I think you have already broken all the State Side Records, except drag racing. Maybe we should buy you a set of Drag Slicks instaed of all those heavy street tires you have been running. Thanks for keeping us all posted on track events, really looking forward to the Top Speed Seven Record at the Texas Mile. :7drive:

[7evin]

11Budlite

 

Thanks for the great links and info.

 

In reference to the blatchat post by AdamHay

 

1. Longer nose with smaller air intake

2. Faired in skinny front wheels with integrated fenders

3. No screen/mirrors/lights, a rigid driver's half door and a hard passenger tonneau

4. No cage, just a small hoop behind the driver's head

5. Skinnyish rear wheels and spats with bolt on side pods to cleave the air past the rear wings (which would have holes or louvres in the back of them).

6. Rigid boot cover with a spoiler extending over the rear to reduce turbulence

7. A rear diffuser to aid air flow under the car (works with the extended boot cover)

8. Fully panelled underbelly

9. Inboard front suspension (not much gain)

10. Aero wishbones (even less gain)

 

Thanks DeanG

 

I have been busting A, all week to address several of these issues to clean and strengthen the car up for this coming months events.

 

1. can't do much about this.

2. running 3.5 in. front tires if everything work out ok.

3. no changes

4. The s2k is fairly clean here.

5. I have been working on a way to clean up the sides of the car, but do not think it will be ready in time. Skinny rear tires will not work for us because we can't get enough bite with them to reach our top speed in one mile.

6. Good idea but again its a time thing.

7. I think this will be a big help. The rear of the car is presenting the biggest challenge.

8. In progress.

9. gain not feasible.

10. same

11. HP, HP , HP.... I guess at this point is going to be how much we can safely squeeze out of her.

 

Maybe I can promise her some chocolate..... seems to work with my wife ...

 

 

 

Thanks Brian, We will give it our best.

 

cheers

7

 

 

 

 

[DB6]

Damn, I feel like I am in a tumble dryer at 90 mph in my car,lol.

[BobDrye]

7evin:

Lower the car to minimize the air drag under the car. Going from 175 to over 200 will probably take an additional 150 hp or so. Can you run without the wings and control the car above 175?

 

 

 

 

 

 

http://www.usa7s.com/aspnetforum/upload/253874069_leaving.gif

[7evin]

7evin:

Lower the car to minimize the air drag under the car. Going from 175 to over 200 will probably take an additional 150 hp or so. Can you run without the wings and control the car above 175?

 

 

Hey Bob,

 

 

You're on the money as usual. I have about 2 inches of clearance for the oil pan.

I have dropped the front wing and added a spring loaded suspension system to it to allow

it to move up if it hits something. I have also skinned the entire bottom of the car.

 

I put the smaller pulley (90mm vs 100mm) on the supercharger today and took it for a drive.

Reminded me of that ride I took with you in your car.... My wife was with me, She said "Holy Shit...

that is scary..." ( I didn't tell her it scared me too... ) Its almost impossible to look at the gauges to see what is going on. The first 4 gears happen so fast that is all you can do to keep it on the road. 5th gear you can look, but your way over a 100 mph so you can only glance at them for a split second. On a track its much easier.

 

I have an 85mm pulley but I don't think I am going to install it. We are already at 6 psi when it goes into Vtech (5500 rpms). I feels like its going to wheelie.

 

Wing issue

The problem that we are up against is that we need the rear wing to give enough down force to keep traction on the rear tires.

Without the wing on the front anything over 160 gets rather dicey. You can control it but

it does not give you warm fuzzes AT ALL.... With the wing on it is absolutely planted.

 

I may attempt a run without them.....

 

Thanks for the input, If you have any other ideas please share them.

 

Did you get your freeze plug issue fixed?

 

Cheers

7

[BobDrye]

7evin:

6psi is like a 22 and 24 psi is what you use to bag an elephant! I can't wait till we meet in Branson next year. Could you move the rear wing so that it's above your head? I just think that the "wall" gets pretty dense above 175.

 

I'm taking the head to the machine shop for a little P&P, valve springs and cams. Going to try for 600hp to keep up with you. John Lee @ Inline Pro is having great sucess with his S2000 stroker kits!

 

Lately I'm becoming Audiophile, building a 52 speaker Tripolar M&K surround home theater system.

 

http://www.usa7s.com/aspnetforum/upload/1014960720_hissyfit.gif

[7evin]

Hey Bob, When you start hunting elephants with that beast of a 7, I'll bring my truck, trailer and video camera and we will own youtube...

 

I could move the wing but I'm afraid that cause other issues and make the car much harder to get in and out of.

The further back the wing is mounted the more leverage you have on the back of the car.

 

600 hp man o man that is going to be scary... I'm sure you home theater will be just as crazy.

 

Thanks for your input.

 

Cheers

7evin