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LongDuck 05-07-22 01:31 AM

Anyone who's serious about control at high speeds doesn't care what it looks like. It could be a giant railway cow deflector mounted out in front, and if it helped keep the nose down and the tires in contact with the ground - everyone on the race track would be running it.

The reality is that form follows function. When the SA and FB was released, they used actual wind tunnels, not computer modeled aerodynamics. They found a design that looked sporty, didn't hang up on curbs, and protected the radiator. That's all they really cared about from the factory. Once IMSA racers got a hold of it, and then Spa win in 1983(?), and it was literally off to the races. Every 1st Gen race car thereafter had an airdam because it keeps the nose down at speed, and your tires in contact so you can steer safely and effectively.

I've driven an SA and FB with no airdam, and the FB design bumper shape helps immensely to kill lift at anything over 90mph. Maybe it's the smoothness of the blending into the quarters, or the brake cooling slots in the bottom...? Hard to say, but both designs were immensely improved with a proper airdam - either Kamei curved front dam to counteract the lift from the lower valence, or the Mariah Mode4 which includes driving light cutouts. Both of these tamed all lift at speed, and builds confidence for the driver when going fast. Once you feel that benefit behind the wheel, you don't care what it looks like - just that it works so well.

Benjamin4456 05-07-22 01:36 AM


Originally Posted by LongDuck (Post 12517260)
Anyone who's serious about control at high speeds doesn't care what it looks like. It could be a giant railway cow deflector mounted out in front, and if it helped keep the nose down and the tires in contact with the ground - everyone on the race track would be running it.

The reality is that form follows function. When the SA and FB was released, they used actual wind tunnels, not computer modeled aerodynamics. They found a design that looked sporty, didn't hang up on curbs, and protected the radiator. That's all they really cared about from the factory. Once IMSA racers got a hold of it, and then Spa win in 1983(?), and it was literally off to the races. Every 1st Gen race car thereafter had an airdam because it keeps the nose down at speed, and your tires in contact so you can steer safely and effectively.

I've driven an SA and FB with no airdam, and the FB design bumper shape helps immensely to kill lift at anything over 90mph. Maybe it's the smoothness of the blending into the quarters, or the brake cooling slots in the bottom...? Hard to say, but both designs were immensely improved with a proper airdam - either Kamei curved front dam to counteract the lift from the lower valence, or the Mariah Mode4 which includes driving light cutouts. Both of these tamed all lift at speed, and builds confidence for the driver when going fast. Once you feel that benefit behind the wheel, you don't care what it looks like - just that it works so well.

Totally in agreement. As I mentioned, mine is just a street car and so speeds that high are a rarity in the first place. Perhaps someday it'll get a better front end, but for now I enjoy the stock body with a 12AT hidden within.

ATC529R 05-07-22 08:51 AM

Just downloaded gps/speed app. I’ll see how she feels at speed and actually know how fast I am going.

I don’t plan on running crazy. But I’ll run it to at least 120 and see how she feels.

j9fd3s 05-07-22 09:17 AM


Originally Posted by chuyler1 (Post 12517203)
Yeah, the lip I think is stock Series 1 but Series 2-3 redesign is missing it. I've been tempted to put a lip on my Series 3 but the common one available today covers up the brake ducts and I don't much care for the IMSA lip. Trying to find more picks of the Racing Beat car just to see if they covered up some of the frontal area or anything.

the class they are in is kind of odd, but they needed to keep the exterior completely stock. obviously the engine wasn't. the article is in one of the stickies, its pretty neat.
basically its a 13B Peripheral port with a 55mm weber, ~320hp. they used a 4 speed, because its more efficient than the overdrive. car got lowered, and that is about it.

ATC529R 05-07-22 03:45 PM

Just took her out. Mind you new suspension all around, clutch, flywheel etc. so a lot done and wasn’t gonna go crazy.

cruising in 4 th and gunned it for a second, hit fifth with barely a blip into it and look and was doing 122. Gets there real fast. Very stable. Very stable.

My teen daughter usually rides with me, as it’s our thing. When I take it out alone I’ll run her up to 150 or more and see how she feels.

bonus point. Last turn on way home saw a decked out roush mustang behind me and went past my house cause I knew he’d be down. Short strip, but I was waiting on him and let him get the jump. Whipped him pretty good to where I had to change lanes in 4th in front of him..but I was well beyond cutting him off. He was videoing me at they light. Lol

chuyler1 05-08-22 09:42 PM

Did you just inform us that you are doing 150mph on Florida public roads?


Maxwedge 05-08-22 09:47 PM


Originally Posted by chuyler1 (Post 12517468)
Did you just inform us that you are doing 150mph on Florida public roads?

You have to drive like that to keep the Florida tweekers from steeling your cat converter.

mustanghammer 05-09-22 09:08 AM

I got my race car up to just a hair under 132 at Indy last year. Max top speed for my car at that track was 135 with a 4.30 rear end and an 8500RPM rev limit. I use this calculator to determine rear end gear changes in my race car as well as calculating the best tire diameter for my Autox mustang in 2nd gear. https://www.racegearbox.com/gear-ratio-calculator/

As far as stability at speed, I have never found tire diameter to be relevant other than a taller tire can equal more top speed if there is room to get there. Controlling aerodynamic lift and overall stability is the key. From my Indy experience I can say that a rear wing combined with an air dam makes a huge difference. To the extent that my race car at 120+ feels like my street Mustang at 70-80MPH.


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