[04gtvert]

Just wondered what you guys with 4.10's are doing to launch with street tires. Should I be launching in 2nd or 1st. Slicks are not an option at the moment. Any tips will be appreciated!

[02StangGToWNEr]

I don't know what Rpms these guys are launching at, but you definatly wanna launch in 1st.

[TheUNZippee!]

Manual transmission shifting help.

I'll pass along what I have learned over a few years.

Before 10 people say it after I post this, let me say as a warning that all these methods are for racing, not day to day driving, and yes, they are hard on your car. It's hard on the clutch, the transmission, the rear end, and the engine. And that's assuming you don't blow a shift.

Launching.

Okay. The first thing in racing is the launch. This depends greatly on your car & how much power it makes, what gears you have, what tires you have, and how sticky the track is. Atmospheric conditions also play a part in how your car runs.

The best launch is one where there is no wheel spin. Wheel spin = less forward movement. Try dropping your clutch at 2000 rpm. If the engine bogs down, you need a higher rpm launch. If you light the tires up, you need a lower rpm launch. Work your way up and down in 100 rpm increments until you find your car's sweet spot.
Sometimes, particularly in cars with lots of power, or in cars with an open differential (non-posi), or on a shitty track surface, you find that no matter where you dump the clutch, you spin the tires too much. In this case, sometimes you have to sidestep, or slip the clutch on the launch. This means slowly letting the clutch out as you roll on to the throttle to launch as hard as you can but without spinning the tires.

Shifting.

The best result for racing is power shifting. It sounds easy in principle, but it takes concentration, as a blown shift can be disastrous, especially if you are running a car with no rev limiter.

To perform a power shift, you keep your right foot on the accelerator pedal during the shift. When it's time to shift, keep the accelerator wide open. With your left foot, you stab the clutch in one quick motion, down and up, moving the shifter to the next gear as your leg is descending & disengaging the clutch. The clutch is only disengaged for a split second, just enough for you to ram it in to the next gear.

How do you know at what rpm to make the power shift? Again, this depends on the car. The reason you power shift is the quicker shift helps keep the rpm up higher where the power is. So this is also a trial & error thing, and takes you getting to know your car. If you are driving a typical Mustang GT that makes it's peak horsepower around 5700 rpm, stab the clutch right at 5700 rpm. Pay attention. If you do it right, the rpm should jump up just shy of your rev limiter, and then when the clutch re-engages, your rpm will still be right where all the horsepower is. Sometimes you're better off making the shift a little sooner in the rpm range, sometimes a little higher. If you bounce it off the rev limiter, you've made the shift too late, or at too high an rpm. You have to work at it until you get the best result for your car.


p.s. breaking shit is cool.

[02StangGToWNEr]

Originally Posted by TheUNZippee! Manual transmission shifting help. I'll pass along what I have learned over a few years. Before 10 people say it after I post this, let me say as a warning that all these methods are for racing, not day to day driving, and yes, they are hard on your car. It's hard on the clutch, the transmission, the rear end, and the engine. And that's assuming you don't blow a shift. Launching. Okay. The first thing in racing is the launch. This depends greatly on your car & how much power it makes, what gears you have, what tires you have, and how sticky the track is. Atmospheric conditions also play a part in how your car runs. The best launch is one where there is no wheel spin. Wheel spin = less forward movement. Try dropping your clutch at 2000 rpm. If the engine bogs down, you need a higher rpm launch. If you light the tires up, you need a lower rpm launch. Work your way up and down in 100 rpm increments until you find your car's sweet spot. Sometimes, particularly in cars with lots of power, or in cars with an open differential (non-posi), or on a shitty track surface, you find that no matter where you dump the clutch, you spin the tires too much. In this case, sometimes you have to sidestep, or slip the clutch on the launch. This means slowly letting the clutch out as you roll on to the throttle to launch as hard as you can but without spinning the tires. Shifting. The best result for racing is power shifting. It sounds easy in principle, but it takes concentration, as a blown shift can be disastrous, especially if you are running a car with no rev limiter. To perform a power shift, you keep your right foot on the accelerator pedal during the shift. When it's time to shift, keep the accelerator wide open. With your left foot, you stab the clutch in one quick motion, down and up, moving the shifter to the next gear as your leg is descending & disengaging the clutch. The clutch is only disengaged for a split second, just enough for you to ram it in to the next gear. How do you know at what rpm to make the power shift? Again, this depends on the car. The reason you power shift is the quicker shift helps keep the rpm up higher where the power is. So this is also a trial & error thing, and takes you getting to know your car. If you are driving a typical Mustang GT that makes it's peak horsepower around 5700 rpm, stab the clutch right at 5700 rpm. Pay attention. If you do it right, the rpm should jump up just shy of your rev limiter, and then when the clutch re-engages, your rpm will still be right where all the horsepower is. Sometimes you're better off making the shift a little sooner in the rpm range, sometimes a little higher. If you bounce it off the rev limiter, you've made the shift too late, or at too high an rpm. You have to work at it until you get the best result for your car. p.s. breaking shit is cool.

Breaking shit is only cool if you have the money to buy the uprades needed.

[TheUNZippee!]

Agreed! LoL

[04gtvert]

Thanks for the info. What do u guys think about launching in 2nd though. 1st gear at any rpm just fries the tires, and it does the same when I hit 2nd so I cant go WOT until halfway through 2nd. I have pretty new BFG G-force sports. My mods are listed below.

[the real shocker]

if you launch in 2nd you will bog pretty bad.... if you launch it pretty high in 2nd it will spin really good and then bog

[02StangGToWNEr]

Originally Posted by 04gtvert Thanks for the info. What do u guys think about launching in 2nd though. 1st gear at any rpm just fries the tires, and it does the same when I hit 2nd so I cant go WOT until halfway through 2nd. I have pretty new BFG G-force sports. My mods are listed below.

Like I said above, your better off launching in 1st. If you launch in 2nd, you will get worse 1/4 mile times.

[TheUNZippee!]

You have to try the sidestep method. Letting the clutch out slowly as you roll on the throttle as hard as you can, right up to the point to where the tires are going to break loose.

2nd gear launches can be done in a car with real power, but not by an average everyday street machine like ours.

You may just also have a real shitty track where you are.

How much are you heating the tires up in the box? Street radials don't need a huge heater, just a brief burn to clean them off and get them warm.

What tire pressure are you running? You can also play with the pressure in the tire. Try lowering the psi bit by bit, although be careful, as with a street radial you can't run low single digit psi numbers like you can with a slick.

[04gtvert]

Actually I haven't been back to the track since I got the 4.10s. That's why I'm asking. I am going on Fri. But on the street I haven't been able to get the launch down. Tire pressure was my next question. What psi do u recommend? I was thinking 15-18?

[the real shocker]

i usually have mine about 18-20

[TheUNZippee!]

What tires are you running? For example, a typical BFG drag radial should never be run below 12 psi. Most performance street radials probably shoudln't be below 15-18 psi.

[04gtvert]

BFG G-force sport

[TheUNZippee!]

Try them around 22, and go from there. I wouldn't drop them below 18, but I think you'll see good results somewhere around the 20 psi mark.