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« on: May 03, 2024, 12:23:00 PM »
I guess that I must have missed this thread the first time, so here is my 2 cents worth on the whole deal. Years ago, I had a mild street strip 70 R code Mach 1. It had a mild solid lifter cam, headers, and a modified Edelbrock Streetmaster intake, with a Holey 780, and had the factory big spline close ratio Toploader, and 4.30 gears and a Detroit Locker. With 28@ tall slicks, it ran mid 12s at 112 MPH, but it felt like it really wanted my gear. But being mostly a street car, even the 4.30s sucked on the freeway, even with the 55 MPH speed limit at that time. One weekend, a buddy lent me his big spline, wide ratio Toploader, which had the 1 3/8" input welded to a wide ratio front gear, so it was a 2.78 1rst gear ratio, with the cluster and all the remaining gears regular wide ratio parts. Back in those days, dragstrips did not have 60 foot timers, but the car felt so much stronger off the line, but when I hit 4th , it broke the 31 spline mainshaft, so I coasted the 2nd half of the 1/4 mile. But I am sure the car was on a pass at least 3 tenths quicker than it ever did with the close ratio. On one long freeway trip with the car, over 300 miles each way, all freeway, I swapped in a 3.00 center section, and although it was fine on the freeway, it absolutely sucked in town, especially from a dead stop. It was embarrassing how slow the car felt.
On my current car, a 4000 + pound (with driver), 59 2 door sedan, with a moderate, aluminum headed .030" 428 CJ, I am running a small input output SB Toploader, and I have 3 different 9" center sections that I swap as required. The "main" is a 31 spline N case with 3.50 gears and a detroit locker., for the occasional trip to the dragstrip, I have a 4.33 ratio with a spool, and for freeway trips, I have the original 2.91 gears, on a 31 spline open. I have used all 3 center sections every year since I put the car on the road 4 years ago, the 3.50s are a nice combination for general street driving, and on the freeway at 60-65 MPH, the 428 is revving 26-2700 RPM, which sounds pretty revvy with the 4" stroke and loudish exhaust system. The 4.33s are much better than the 3.50s at the track, but absolutely suck on the freeway (3400 RPM), and even in town, they are a bit much, as I live in a semi rural area, so the street that I live on is a 50 MPH speed limit, and everything is close to 10 miles away. The 2.91s are currently in the car, and freeway speed puts the tach at about 2100 RPM, but hard to be positive, as the speedo is calibrated for the 3.50s. But the 2.91s are pretty doggy starting off from a dead stop. Keep in mind, that my 428 made 470 HP at 5400 RPM, and 515 ft/lbs of torque at 3000 RPM, so this is hardly a peaky, high RPM engine. With the wide ratio and 3.50 rear, it has the same starting line ratio as a close ratio with 4.2 ratio. Having owned both close and wide ratio Toploaders, in both 351C 4V 70 Mustangs, and several 428 CJ cars, I can`t imagine anybody that has actually driven similar vehicles with both transmissions, would ever even consider choosing a close ratio over a wide, UNLESS they were actually road racing the car. The 5.0 FOX Mustangs had 3.35 first gear ratios in the T5 5 speed, and even with 3.08 gears, had more starting line overall ratio as a CR Toploader with 4.30s. I can imagine that despite being quite light, a 5.0 Fox Mustang with a CR Toploader would be an absolute slug without at least 4.88-5.13 gears at the track. If a person doesn`t care about performance at all, and just wants a 4 speed, then I suppose the CR would be acceptable, but I would never choose one again. The only thing that would be worse for performance, short of an automatic, would be a 3 speed manual, with or without overdrive, or one of those 3/4 speed OD "Orion" transmissions from a late 70s-early 80s Granada or PU/Van.