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3.31 gears vs. 3.73 gears for road course

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Grant 302

basic and well known psychic
I don't think you can go wrong with 3.31s on a GT, but if you are on stock diameter tires, then you may only 'need' 3.55s

I have 3.73s on my GT and with 25.6" tall tires, the top of 4th is only 106mph and 5th is just under 140.
 
Budget Boss I run ECR four or five times a year and 3.73s in 4th on the backstretch down to turn 7 is killing time and building unnecessary heat. I'm on the limiter 7500 for 100 to 200 feet. My Boss is all stock and raising the limiter is not an option. In the summer heat I have to short shift at 6500 and use 5th to keep the engine heat/oil temp down. The Boss just doesn't like 7000k plus rpms in the Texas heat. Shifting at 6500 allows oil temp to stay within acceptable limits (260). I also have to short shift to 4th on the short straight for turn 3 to stay off the limiter in 3rd. I would love to have 3.31s for ECR since on the long straights short shifting would not be necessary with the added gear, but each track is different. I'm not sure how TWS will work out with 3.73s as I have not run the Boss there yet. My guess is on the long straights at TWS I'll have to use 5th and short shift as well.

My mods are limited to: FR Brake cooling ducts, PFC 01 brake pads, Steeda Boss springs. Tires/wheels are stock.
 
HackBoss302 said:
Budget Boss I run ECR four or five times a year and 3.73s in 4th on the backstretch down to turn 7 is killing time and building unnecessary heat. I'm on the limiter 7500 for 100 to 200 feet. My Boss is all stock and raising the limiter is not an option. In the summer heat I have to short shift at 6500 and use 5th to keep the engine heat/oil temp down. The Boss just doesn't like 7000k plus rpms in the Texas heat. Shifting at 6500 allows oil temp to stay within acceptable limits (260). I also have to short shift to 4th on the short straight for turn 3 to stay off the limiter in 3rd. I would love to have 3.31s for ECR since on the long straights short shifting would not be necessary with the added gear, but each track is different. I'm not sure how TWS will work out with 3.73s as I have not run the Boss there yet. My guess is on the long straights at TWS I'll have to use 5th and short shift as well.

My mods are limited to: FR Brake cooling ducts, PFC 01 brake pads, Steeda Boss springs. Tires/wheels are stock.

On the back stretch going into turn 7 I get into 5th gear with a speed of 120mph. I shift at 6500 my rev limit is 7000. However, after 6500 there really isn't any torque on the GTs. My engine temp runs 230 through the summer months. One of the things I did to get more air flow is to use the CDC GT500 grill. Also, use Royal Purple Ice (water wetter) to help with the heat.

Are you going to ECR on Feb 22nd?
 

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