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Anyone know?

I'm curious to see if I'm shifting correctly down the 1/4. I can't seem to do any better then [email protected]/118 w/ 1.9ish '60 on pilots.

To make it EVEN WORSE....

Went to the track Tuesday w/ BFG Radials and couldn't even get below [email protected] with 2.0 60'. ANY SUGGESTIONS FROM EXPERTS!

I only ran 3 times because it got too crowded and I didn't feel like waiting an hour in line to run. Better burnout? HELP HELP HELP!

Thanks in advance!
 

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Make sure you heat the tires until they start to smoke. No guarantee that they'll have enough heat but it helps.
As for 3.73s, that should be an almost ideal gear for your combo IF you never go over 500-525 hp. Shift points don't change.
If you have a dyno report, multiply gear ratio by torque at shift point, and figure out where you'll be at rpm-wise after the shift. If your torque is substantially higher in the lower gear, you should hold the gear longer. Many people say to shift at 5500rpm, but scientifically I should do better shifting at 6000. Yeah, you have more torque at 3500 that 5500 rpm, but don't forget about the torque multiplier of the gear you're in.

See if that makes sense and good luck.
 

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I know by experience that the 3.73's are a great gear set for the quarter, but mine runout of room at the top end. My best was a [email protected] I figured I should have gone [email protected], but staying in fourth through the lights was a mistake. I should have shifted to 5th because the engine was gasping for the end. Next time I hit the track I will do the final shift. I have a 96 RT/10 with Borla headers, no cats and TNT exhaust. I like to shift at 5500.
 

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yeah, I agree. The cam in your '96 really wants a 5500 rpm shift point, even with the headers and exhaust. If you want to keep your 3.73s, you should probably go to the 1.7 roller rockers. This will shift your powerband up a tad and you'll pull harder in high gear. You'll still be spinning hard crossing the line, but your engine will be breathing through a slightly larger "straw". You should stay in fourth, however. Doing the math with a 26" wheel, a 120 mph trap speed will be the upper limits with this gear.
 

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Acceleration is based upon torque, look at your torque curve from a previous dyno run. The optimum accleration is achieved when the rpm drop from the shift brings you down to the peak torque.

Shifting to fifth is bad due to the large rpm drop, you are better off going to 3.55's. The 3.73's are too much (for drag racing) for any modified viper. Look at this link to calculate speed and rpm:

http://chuckware.net/viper/gears.asp

Remember tire size is important, the ET's are almost an inch taller than the the Pilots. I have 3.33's, with the ET's on the car they become little different than the 3.07's with Pilots.

Does anyone know the height of the BFG's.
 

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Problem = 3:73 is wrong gear

Solution = Re-Install 3.07 gear

Reason= lower numerical gear means less torque required to initiate wheelspin during initial acceleration.

Drag race is ALL about what happens in the first 60'. 3.07 gear will help put power to the ground if the car is driven correctly. Keep in mind that it is the TORQUE not the HP that moves the mass of the vehicle, you are waisting your torque in two ways;

1. With wheelspin from the initial shock of the lower numerical gear

2. Not being in the torque band long enough in each gear to sufficeintly accelerate the vehicle.

Enough free advice.

JEDI
 

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I'm cutting a 1.8 60' time fairly consistantly and have cut a couple 1.6's. I use Kumho's so they are not that tall in comparision to the BFGs.
 

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Unless you are drag racing all of the time and/or have plans to add a LOT more HP soon, I wouldn't go back to 3.07 gears.

I agree that 3.77 gears are a bit too steep for racing the Viper, but I have 3.55s and they are a great compromise between having a great pull of torque on the street, and not running out of gear in the 1/4.

3.77 gears should take you up to 124MPH in 4th without having to shift, so you should have a fair amount of room to go before hitting your rev limiter.
If your engine is running out of steam up top, you might look at getting some better breathing mods.

Track prep varies, but you do probably need to warm up the tires a bit more with the BFGs. You should be able to get under 2.0 with the BFGs, and better trap times will result from a better 60' time.
 
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