I've had these discussions before with guys trying to pick the right gearing in T56s. Lots of folks like the tall 2.66 first, because of the short ratios, but the problem is that it leads to situations like the one I'm in, a first world problem to be sure.
I got this trans from my best friend for a good deal, and decided to put it in Black Jack so that I could eventually spray and put sticky tires on the car.
With the 3.35 first in the T5, the car would 60' as low as 1.83 on stock size Goodyear all-seasons, leaving off of near idle. I'd just do my best to get the clutch out smoothly and let the super short gear to all the work.
Now, after having Black Jack out at the 1/8 event at Foxtoberfest, I've learned that it wants to leave off of the limiter. On Nittos, which aren't fantastic Drag Radials but are still far better than the previous Goodyears, a 6k RPM launch took me to a 1.86 best. I attribute the need for the launch RPM to this 25% difference in Gear Ratio.
So, here's the crux of it, I'm installing a 150-200 shot of nitrous, and because it's still 1:1 in 4th with my 4.10s, it still runs out of gear at ~109 mph. Beer math says that I might be running over 120 in the 1/4. 3.73s would be about perfect for that, but I'm concerned that it'll launch like a dog. Will nitrous make up the difference on the launch, and allow me to prevent bogging? Santa brought me an Eaton Detroit TrueTrac for xMas, and I was thinking I'd do the gears while in there.
Wish my best friend listened when I advised the 2.97 first gear, wide-ratio, T56.
I got this trans from my best friend for a good deal, and decided to put it in Black Jack so that I could eventually spray and put sticky tires on the car.
With the 3.35 first in the T5, the car would 60' as low as 1.83 on stock size Goodyear all-seasons, leaving off of near idle. I'd just do my best to get the clutch out smoothly and let the super short gear to all the work.
Now, after having Black Jack out at the 1/8 event at Foxtoberfest, I've learned that it wants to leave off of the limiter. On Nittos, which aren't fantastic Drag Radials but are still far better than the previous Goodyears, a 6k RPM launch took me to a 1.86 best. I attribute the need for the launch RPM to this 25% difference in Gear Ratio.
So, here's the crux of it, I'm installing a 150-200 shot of nitrous, and because it's still 1:1 in 4th with my 4.10s, it still runs out of gear at ~109 mph. Beer math says that I might be running over 120 in the 1/4. 3.73s would be about perfect for that, but I'm concerned that it'll launch like a dog. Will nitrous make up the difference on the launch, and allow me to prevent bogging? Santa brought me an Eaton Detroit TrueTrac for xMas, and I was thinking I'd do the gears while in there.
Wish my best friend listened when I advised the 2.97 first gear, wide-ratio, T56.
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