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Discussion Starter · #1 ·
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After the next mod the 69 War Horse will be able to do 180 mph plus if I can keep it on the ground. Besides tires and rear sway bar what would be your suggestions to keep it on the ground. Remember it is a Coupe.

Jess
 

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You should remember...theoricial max velocity acheivable for an RPM, Gearing, and tire combination do not equate to vehicle top speed. The aerodynamics of the mustang are that of a brick which will introduce significant drag.
 
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I honestly think you're shooting a bit high if you want 180 MPH. I've got an uncle with a 69 Camaro, full drag car, big block chevy, that runs on alcohol, and it doesn't go 180 MPH. I mean, I'm sure it would if it had more than a 1/4 mile to run it in, but I assume we're talking 1/4 mile times. I mean, my little 289 will probably get to 180 MPH with the right gearing, it just may take a while to get there. :eyepoppin
 

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Jess said:
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After the next mod the 69 War Horse will be able to do 180 mph plus if I can keep it on the ground. Besides tires and rear sway bar what would be your suggestions to keep it on the ground. Remember it is a Coupe.

Jess
What basis are you using to estimate the 180+Mph?
 

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Discussion Starter · #5 ·
Ground Effects

Well lets start with 5500 rpm, 28 inch tall tires, 3.73 rear gears, final drive of .63, and a whole lot of horse power???

Jess
 

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Jess said:
Well lets start with 5500 rpm, 28 inch tall tires, 3.73 rear gears, final drive of .63, and a whole lot of horse power???

Jess
The theoritical equation works out to about 178-180
http://www.corral.net/tech/gearcalc.html

However, to properly align expectations the car will never see that speed because of tire friction, wind drag, etc....top speed will be sub 140 IMO. Another thing to remember is the OD gear in trannys are rarely (if ever) designed to allow the car to acheive 5500 RPM while in them. The car's top theoricial speed is best calculated using the 1:1 tranny ratio since in a race you would not be using OD.

Here is a theoretical speed graph I made for my car so I could have an idea of speed based on RPM since the speedo hasn't been hooked up. If I stepped up to a 28 inch tire from a 25.5 I would have very similar numbers to yours. While no one has yet to pass the car 5000 in OD feels extremely unsafe because of lift and I know I am not going anywhere close to what the theory says I should be (I would guess sub 110). So to answer the core question at higher speeds and air damn/spoiler on the front will help you prevent lift (until a point) I see little benefits in side skirts.

http://www.dodgestang.com/speedchart.jpg
 

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Discussion Starter · #7 ·
Ground Effects

dodgestang said:
The theoritical equation works out to about 178-180
http://www.corral.net/tech/gearcalc.html

However, to properly align expectations the car will never see that speed because of tire friction, wind drag, etc....top speed will be sub 140 IMO. Another thing to remember is the OD gear in trannys are rarely (if ever) designed to allow the car to acheive 5500 RPM while in them. The car's top theoricial speed is best calculated using the 1:1 tranny ratio since in a race you would not be using OD.

Here is a theoretical speed graph I made for my car so I could have an idea of speed based on RPM since the speedo hasn't been hooked up. If I stepped up to a 28 inch tire from a 25.5 I would have very similar numbers to yours. While no one has yet to pass the car 5000 in OD feels extremely unsafe because of lift and I know I am not going anywhere close to what the theory says I should be (I would guess sub 110). So to answer the core question at higher speeds and air damn/spoiler on the front will help you prevent lift (until a point) I see little benefits in side skirts.

http://www.dodgestang.com/speedchart.jpg
I beg to differ with you. According to Stan Weiss's website http://users.erols.com/srweiss/

5500 rpm
27.5 tire diameter
3.73 rear gears
.63 final drive

Gives you a top speed of 191.561. Check it out. I weigh less than the 06 retro and I drive the real retro brick that is going to pull the 05 and 06 shorts off when they want to dance at 70 and 80 mph on the freeway don't you think?

Jess
 

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Hey more power to you on it.

Out of curiosity what street tire are you running that is 27.5?

The closest I can find is a 255 50 17 at 27.1....so I upped the sidewall to 55 for calculation
 
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I would brace the hell out of that car too bro. More speed equals more risk, safety first! I'd a say a full 12-point roll cage at the very least. Not to mention racing seats and at least a 5-point harness. Then you'll definitely want subframe connectors, I'd suggest TCP's since they not only tie the front to the back, but from one side to another as well.
 

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Discussion Starter · #10 ·
Ground Effects

dodgestang said:
Hey more power to you on it.

Out of curiosity what street tire are you running that is 27.5?

The closest I can find is a 255 50 17 at 27.1....so I upped the sidewall to 55 for calculation
That is the problem right now T/A Redials 255 x 60 x 15 on the rear. Good run around town tire. According to their book they are 27.5. They are rated at 90-100 top speed. Tires are a main issue. Brains are another issue. The 69 has an ocean for a wheel well after you flatten the seams.

Would have to do lots to the frame and roll cage the beast. The other problem that kills anyone in a fast Mustang, which was offered by someone else is lift. These cars aren't made for top speed driving. I've driven my 69 since 69 and I know how twitchie it gets on top end. I use to drive the War Horse back and forth West Coast to East Coast and back all the time when I was young and in the service. My last year in the Air Force went from Sacramento to Panama City Florida and back three times. On those long desert stretches air would build up under the car and it would float and I would have to back off, those old Dunlap GT Qualifiers saved me many a time when I was stuped.

Top speed driving is for Nascar boys. I just hate it when young kids who haven't seen life want to throw it away at 70/80 mph on the freeway and kill someone else along the way. They are as bad as the street racers and ricers.

It's just a dream to have the fastest and the badest. Projects like this is what keeps us gray beards afloat and our mad money spent. Build dreams to show not show off. No one will see your beauty if it is wrecked except the ghosts in the junkyard.

Jess
 

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One thing I would keep in mind for high speed running. If you look at the 'super cars' that are designed to actually run above the 130-140 mark. They have smoother undersides with vents in strategic locations to create a pressure change under the car thereby using this pressure change created by the passage of air at high speeds under the car to 'suck' it down.
 
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Well, not only adding ground effects, but you're going to need to drop that nose within about an inch of the ground. It's gonna have to sit low. Wide tires will be be a plus to keep you stabilized. And instead of making the motor do all the work, you might want to consider taking some weight from the car, such as getting a complete fiberglass front-end.

Man, I think you'd be wasting a lot of time and money with this. Where exactly do you plan to drive this car and actually get to 180 MPH? The only place LEGALLY that I can think is the Salt Flats.

And let me tell you somethin dude, I had a friend hit the wall at 120 MPH, and that was a frightening sight. He could have VERY easily died, but luckily the car never overturned or flipped. He was actually doing about 140 MPH but he was doing about 120 when he actually made contact with the wall. This stuff is not something to mess around with man, you really gotta know what you are doing.
 

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Discussion Starter · #13 ·
Effects fpr 180mph

Acooljt

It is a dream we all have, that is what makes us Americans, that is what makes us great, to be the fastest and the baddest. We all have it. That is why we are here. It is fun to build and waste my mad money. It is a stress reliever of the job like my wife. It is a well that I throw money down. It is fun to take it to car shows and see the questions in their eyes before they ask. Individuals are right, there is no place to drive it in the land of the big BX/PX, but it sure as hell is fun to know you have it.

Jess
 

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Jess said:
Individuals are right, there is no place to drive it in the land of the big BX/PX, but it sure as hell is fun to know you have it.

Jess
PISH. I do that in my driveway all the time :winks
 
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I'm not saying there's anything wrong with pissing away your money on your car, hell I've been doing it for 3 and a half years now. I mean, it's better than putting it up your nose or somethin stupid like that. My point is that, why have something so fast and not be able to use it? Or say it will do 180 in the 1/4, you're gonna have to do some MAJOR modifying to that car to stay safe. Adding a spoiler and ground effects are the least of your worries.

I mean, my friend that I was speaking about who hit the wall at 120, he builds full-tube chassis and drag cars for a living. Yes, that fastest of the fast. And currently in his garage is a 65 Fastback that sits incredibly low to the ground and how a motor that will definitely meet or exceed 180 MPH(a blown and injected 404w). This car sits so low that the top of the roof sits at 50 inches from the ground(which is about at your chest on a 6'0" tall guy). Yeah, and the guy he's making it for specified that he also wanted it street legal. Yeah, it's one killer car. But you know what, it's also got a full-tube chromoly chassis with funny car roll cage, and all of that is NHRA certified with the tag to prove it. My point is, you can go as fast as you want, but the safety better be there. I'd rather have a car that topped out at 80 MPH but I dumped a crapload into it for a full cage and all the correct safety equipment than to have a car that tops out at 180 MPH and has maybe a roll cage and seatbelts. The safety has got to be there man, I can't stress that enough. It seems like you're really overlooking it. Because if you weren't, you'd be more worried than you are acting right now, because it will NOT be cheap.
 

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Discussion Starter · #16 ·
Effects fpr 180mph

acooljt

I am looking now for a cage, something clean and not obnouxes. Can't find a decent looking rear spoiler. This will always be a daily driver even though it only get 6-7 mpg as it is set up. It is the first new car I ever owned and I will pass it on to one of my son in laws(depending upon if they deserve it) or my long serving mechanic/friend/dreamer/adviser/chevy freak.

Jess
 
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Well dude, I'll tell you now, the cage you're going to need is definitely going to be obnoxious, because it's gonna be a full 12-point. If you get any less than that, you'd be crazy. Also, you might want to take your car to a reputable chassis shop to brace the body/chassis for that kind of speed.

Also, I'll let you know now, that if you run a 9.99 or faster at a IHRA or NHRA sanctioned track, a lot of times they will make you have a license or you can not drive it. It doesn't take much to get a license, you just have to make a certain amount of passes in a CERTIFIED car. These passes have to be taken by yourself(no one else on the track). After you obtain the license, you are then allowed to play with others. So you might want to make sure it meets NHRA standards. They have a book of all standards that have to be met on their website or any good chassis shop should know.
 
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Also, the rear spoiler you're going to want is not going to be sold by some Mustang shop. Go to a reputable chassis shop and tell them you want a Pro Stock spoiler put on the car.
 

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The old late 60's TransAm racers claimed their Mustangs seemed to "hit a brick wall" around 150mph on the long straights. IIRC it was Parnelli Jones who said that. If you look into the modifications those cars had you'll get some ideas that will get you up that far. To go over 150mph you're looking at doing a lot more, assuming Parnelli knew what he was taliking about. Pretty sure he did.:rolleyes:
You never did state WHERE you wanted to go 180mph. I'm suprised nobody mentioned the "Silver State Challenge". People drive at speeds above 180mph there on a regular basis. Along that line you might want to research Gottlieb's "Big Red Camaro". A '69 that entered one year and took all comers for the win. Keep mind the field included any number of high dollar european imports and even few actual race cars. I've never cared for Camaros but this one came, saw, and kicked ass at an AVERAGE speed of like 192mph (IIRC). Keep in mind this body style is the same one campaigned against the Boss Mustangs in the old TransAm race series and back then they had about the same aerodynamic problems as the Mustangs. Even though it's one of the other brand cars I believe there's a lot to be learned from this particular car if want want to be able to go REALLY fast. I haven't looked lately, but I believe there is website for the Big Red Camaro. I know there are pics online from when it was featured a couple of times in Car Craft magazine.
Speaking of the SS Challenge, a Fox body Mustang won one year back in the 80's. At the time the owner had the best brakes he could find fitted to the car, a four wheel disk set from an SVO. As he crossed the finish line and tried to slow down he literally set fire to all four brakes. Does you little good to go fast if you can't slow down.
My personal goal is to have my car "being capable of" 150mph. On very very rare occasions I imagine. :) The only time it will ever see a dragstrip is on "test and tune" nights. Speeds through the quarter mile don't really interest me, using the dragstrip to work out bugs and see what might break does.
 

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if I was to want to go that fast and of course any man does, I woul have thhe widest tires a most efficient front and rear spoiler capable.
 
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