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Al_C
11-29-2023, 10:30 AM
The latest CD magazine showed up the other day and I was poking around the article about a 0-150-0 test. That got me thinking (which could be a dangerous thing...). How fast can one of our cars (most interested in the roadster) go? Or rather, how fast are you willing to drive it?

A quick search showed a bunch of theoretical discussions, the latest about a month ago, but I couldn't find anything that said "I went XXX mph!" As for me, I've had 8650 to 100 mph, give or take. 94 mph on the track, a little faster trying to keep up with Sten on the interstate ;) Not really noteworthy, but I had to contribute my experience if I expect you to contribute yours...

So, how fast have you gone? Would you try to complete the 0 - 150 - 0 test?

(If this is the crap that is occupying my mind now, I need to get a new project!)

chmhasy
11-29-2023, 11:13 AM
https://www.youtube.com/watch?v=2XmQdcAxDgI

JohnK
11-29-2023, 11:27 AM
I've had mine briefly over 100 just to say I did it, but with a little over 300 on the odometer I'm not interested in pushing it any harder than that until it's had a more thorough shakedown. FWIW - it was still pulling like a freight train at 100.

john42
11-29-2023, 11:32 AM
I hit 135mph (with my old motor on a race track) before I stood on the brakes for the upcoming corner. That's prolly as fast as I would ever want to go. New motor only has 100 miles on it and the weather is too cold to do anything.

Ducky2009
11-29-2023, 11:43 AM
I opened mine up last summer. I was waiting at a light for the on ramp to the expressway, middle of the day, middle of the week, far out of town. After turning the corner, I opened it up and ran through the gears. As I pulled onto the expressway (end of the on ramp) I let off the gas. When I arrived home I pressed the tattletale button. 134 MPH. Don't think I want to go that fast again.

Jeff Kleiner
11-29-2023, 11:59 AM
I’ve done 130 on track at Gateway International and Putnam Park. That’s almost the to the 6,250 RPM rev limiter in 4th gear with a 3.55 rear end. I think that’s enough! Point of interest; my first run at Gateway was without the air dam. The front end was noticably more planted with it at 100+ although the engine did have to work harder to push it.

Don’t forget that our hero Dick Smith did 198 in CSX3035 at Daytona!

Jeff

drewr
11-29-2023, 01:32 PM
None of us drive above the speed limit. I'm shocked... shocked to hear you suggest such a thing!:p

AC Bill
11-29-2023, 01:38 PM
I found that at speeds of 100+, the roadster's front end became light and affected the steering, which is kind of an eerie feeling. Without some added aero's to create downforce, I wouldn't try for 150 mph, although there is no doubt at all it could attain that speed. Keep in mind the speed rating for your tires. Very few available in 15" that you can drive at those speeds, and are street legal.

nuhale
11-29-2023, 01:46 PM
Been north of 100 many times. My top was around 135-40. Keeping up with Sten on the highway Al? That’s not as difficult as presented! Sorry Sten. ��

Jim1855
11-29-2023, 03:24 PM
OK, I feel right at home here. Now a note, the speeds & times were in my first Superformance Roadster not a Factory Five but the aerodynamics aren't much different. Still similar to pushing a Greyhound bus.

Gingerman, track limited, pretty much ran out by about 125.
Grattan, pretty much maxed at 140. About 6,000 rpm in 4th.
VIR South Track, 140 again but could have bumped it an easy 15 if running Full Track. I was coasting to the 90 degree turn off of the straight.
Once past a warm-up lap in the speeds on the tracks were every lap.
Did 155 in 5th early on in my career.
And 157 in 4th on another ride being followed by a friend.

140 is easy and fairly stable. Bumping into the 150+ range is more interesting. This might be where the suspension differences between the SPF and FFR cars really starts to show.

I'm planning on 160 if I ever get the Challenge Car built.

I did get the Car & Driver issue with the 0-150-0 test, piqued my interest as well. Let's see, ran 120@11.8 first time on a strip. Add maybe another 10 seconds to 150 then 10 to brake so maybe low 30 seconds. But I'm just guessing. The CC will be about 200# lighter with another 30 or so hp.

As an observation, past 110-120 every 10mph is a new "zone". The change seems exponential rather than linear. Sensations speed up as must your thinking but your driving inputs need to be calculated and meticulous rather than abrupt and jerky. It's similar to driving on glare ice just warmer.

And a word of caution. Kids - don't do this at home.

My friends wonder about me too. Never said I suffered from excessive common sense.

Jim

Papa
11-29-2023, 03:55 PM
I'm usually too focused on the driving surface to pay any attention to the speedometer, but with the handy digital recall function on my gauge, I can say 113mph is the fastest my car has gone. The fastest I've ever driven is 157mph in a BMW M550i. In that car, getting up to speed was easy. Stopping that 4,000+ car, even with the massive 14" rotors and six piston calipers was the scary part.

ggunter
11-29-2023, 04:03 PM
You all know your insurance companies monitor this forum don't you........

nuhale
11-29-2023, 04:29 PM
You all know your insurance companies monitor this forum don't you........

I was talking km/h in that case…

GoDadGo
11-29-2023, 04:44 PM
134 MPH. Don't think I want to go that fast again.

I ran 10 miles slower (124 MPH) at the drag strip on my first & last pass.
I realized on that day that I'm a wrencher not a racer.
The car was black balled and that's okay.
NHRA Rules are what they are.

Papa
11-29-2023, 04:56 PM
You all know your insurance companies monitor this forum don't you........

Yes, and there are places where it is perfectly legal to stretch your car's legs.

My favorite road sign...

https://thefactoryfiveforum.com/attachment.php?attachmentid=192796&d=1701295115

My favorite traffic light:

https://thefactoryfiveforum.com/attachment.php?attachmentid=192797&d=1701295513

AROCK
11-29-2023, 04:58 PM
I th rumor is a roadster with a 427 stroker hit 155 just after pulling 4th gear. I heard the front tires were barely tapping the pavement. I heard it was a scary ride!!

Fman
11-29-2023, 05:53 PM
110+ for me on multiple occasions on a track day and it got there plenty quick... will never need to go any faster, the car did feel very stable. I actually also really enjoyed the slower driving through the turns, highly recommend anyone with these cars to do a beginner track day will let you really feel the car.

Al_C
11-29-2023, 09:25 PM
This is fun! So far, it looks like Jim1855 has the highest numbers (or did I miss something...) I'm not going to challenge any of these speeds, thank you. I look forward to more responses!

Rsnake
11-29-2023, 10:12 PM
I like this thread.
Here is my top speed at the Silver State Classic in September. Going for 165 in May.
Most of you should recognize the speedometer in the photo
192800

2FAST4U
11-29-2023, 11:45 PM
I had my first cobra up to 130 mph. And I’ve had my 2021 Challenger SPWB up to 145 mph

RoadRacer
11-30-2023, 12:15 AM
I had my GTD40 (UK GT40 replica I built in late 80’s) up to an indicated 165mph at end of Paul Ricard straight (it’s roughly a mile long!) which was a lot of fun right before a sharp right!

No idea what the actual sped was.. this was pre GPS

Gordon Levy
11-30-2023, 12:31 AM
180ish in CSX3035
185ish in a Yates powered Hitech
200++ in several different Can Am cars
170+ in several FFR's roadsters
175+ in a couple different GT40's
175ish in a gen 2 coupe
It's all fun if your willing to drive through it.

F500guy
11-30-2023, 07:30 AM
New Song-"My Miata does 125..." with only 185 HP. Imagine 150+ in cobra with 400+ HP would be pretty easy. Add a little more rake to keep the front end down...

mikeinatlanta
11-30-2023, 07:32 AM
I believe Troys GTM is the only one with a 200, done at the Texas Mile. A few have taken their 65 coupes over 200 at lsr events.

KDubU
11-30-2023, 07:36 AM
In my FF, 110mph. On my bike in my younger years, 154mph.

OSU Cowboy
11-30-2023, 10:47 AM
I touched 125 in SloPoke one time ... it had more, but was more than plenty for me.

J R Jones
11-30-2023, 12:51 PM
Seen at SEMA this year:
https://www.youtube.com/watch?v=vYz-6fnLm9U

310MPH is formidable building there and driving there.
jim

BTW long first gear, followed by wheelspin overspeed and drag chute anticipation which did stabilize the car on throttle lift.

JasonD
11-30-2023, 02:07 PM
Indicated 150, at that point the air is getting hard to push and the nose is light. As mentioned earlier a little rake down in front helps, but I don't think you're going to get away from a light nose without some form of air control.

I can't fathom 198 mph in a roadster without significant aero changes. The difference between 130 and 150 is big, and it keeps growing exponentially after that.

rthomas98
11-30-2023, 03:03 PM
I have not pushed my roadster that fast yet. Only hit 90 at this point. But did take a modified dodge neon up to 135 mph once when I was younger. That was butt puckering and exciting at the same time. So emphasis on the only did it once.

Scott L
12-02-2023, 04:38 PM
I’ve done 130 on track at Gateway International and Putnam Park. That’s almost the to the 6,250 RPM rev limiter in 4th gear with a 3.55 rear end. I think that’s enough! Point of interest; my first run at Gateway was without the air dam. The front end was noticably more planted with it at 100+ although the engine did have to work harder to push it.

Don’t forget that our hero Dick Smith did 198 in CSX3035 at Daytona!

Jeff

I did about the same on the long straight at Thompson in CT (about 3000 feet). At 130 the front end was getting light!

Matt Ries
12-03-2023, 12:10 AM
Mary and I run at Putnam Park and Mid Ohio, with a stock 95 5.0 T5 and 3.55 gears it tops just at 115mph on the back straight at Mid Ohio, and 110 at Putman Park front straight. The little 225horse giving all she has. :) I've never dyno'ed the car and run the timing at a conservative 11 deg. Anybody know how to calculate hp?

Jim1855
12-03-2023, 09:55 AM
Calculating HP....

You could use the DeskTop Dyno software. It provides a reasonably good estimate IF you input the correct information. This takes time and experience. It may also be possibly to compare your engine configuration to other owner's similar builds. This might get a decent "ballpark" estimate.

But you'd be far better off to find a good dyno shop that will test and then tune your engine. A good shop can often find unrealized HP/TQE.

Jim

Matt Ries
12-03-2023, 10:28 AM
Jim, fun thread, spurring interesting thought. Thanks for the Desk Top Dyno idea. Not worth the money on a stock engine for dyno time. Back to daydreaming on more track time!

Al_C
12-03-2023, 01:01 PM
Matt - Jim offered some pretty good ideas! Here's another: I found a 6 minute youtube video on estimating HP. Maybe this will help you. https://www.youtube.com/watch?v=g9Fr6_Ut3a4

Papa
12-03-2023, 01:35 PM
For those not familiar with the BMW M550i's unbelievable acceleration, here is a video clip that shows just how quick this 4,400lb. car is. Skip to 1:41 in the video for a 0-150mph launch.


https://youtu.be/nkra-qUIXzM?si=BHzz0gyGoxn6EJa8

David Hodgkins
12-05-2023, 02:28 PM
I got ol' 5369 up to 122 on the front straight of Willow Springs raceway over a decade ago.

Let's keep the videos to track-only please. Running that fast on the highway is just, well, dumb. Getting it on video and posting it to the internet is even dumber and not condoned here.

https://thefactoryfiveforum.com/attachment.php?attachmentid=1029&d=1300396270

:)

Papa
12-05-2023, 02:54 PM
I got ol' 5369 up to 122 on the front straight of Willow Springs raceway over a decade ago.

Let's keep the videos to track-only please. Running that fast on the highway is just, well, dumb. Getting it on video and posting it to the internet is even dumber and not condoned here.

https://thefactoryfiveforum.com/attachment.php?attachmentid=1029&d=1300396270

:)

David,

I apologize if the video I posted crossed a line, but it is on the Autobahn, where it is perfectly legal
and acceptable, but admittedly not always the smart thing to do depending on traffic conditions.

Dave

David Hodgkins
12-05-2023, 02:59 PM
No worries Dave, thanks for the clarification.
:)

GoDadGo
12-05-2023, 07:24 PM
Please be careful going fast guys because my pal Phil hit the wall at Sebring this past weekend at tripled digit speeds.
He survived with four (4) broken ribs, is black and blue all over but wiped while wiping out his TOJ-206.
I haven't seen the car yet, but it doesn't sound like it is even remotely repairable.
Phil is back home and will hopefully have a speedy recovery.
Shown below is what the car looked like at the 2019 Mitty:

https://youtu.be/zm2RdZ-FJmA

Heck take a ride with him at this year's 2023 Mitty:

https://youtu.be/fGvzBCo3uFk

Again, Please Be Careful Gang!

Scowally
12-08-2023, 07:39 AM
We are all living the Sammy Hagar song… I can’t drive 55

J R Jones
12-08-2023, 11:08 AM
Please be careful going fast guys because my pal Phil hit the wall at Sebring this past weekend at tripled digit speeds.
He survived with four (4) broken ribs, is black and blue all over but wiped while wiping out his TOJ-206.
I haven't seen the car yet, but it doesn't sound like it is even remotely repairable.
Phil is back home and will hopefully have a speedy recovery.
Shown below is what the car looked like at the 2019 Mitty:

https://youtu.be/zm2RdZ-FJmA

Heck take a ride with him at this year's 2023 Mitty:

https://youtu.be/fGvzBCo3uFk

Again, Please Be Careful Gang!

Driving at maximun WFO speed and "careful" is an oxymoron.
jim