And I was laughing because 1300 horsepower in a front wheel drive that is running 225 section width tires is hilarious. Just because somebody does it, does not mean it is a good idea.
My Sentra SE-R w2w racecar has 300whp and even with LSD it has traction issues on 225s
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Yeah it seems nuts but it just works. You can find really old videos from 700whp days street launching against r35 gtr's. You have to remember its a combination or vehicle weight/weight distribution, suspension setup, centre of gravity, longitudinal roll centre, power delivery, axle torque, tires.
Is your sentra a b13/14/15? sr16/20/qr25? Are you having issues with longitudinal or lateral grip?
I am going to make a guess and first say that the reason you have perceived traction issues is that you actually don't have enough HP (
).
Your torque is probably "decent" but falls right after peak leading to making peak torque at 2nd gear cornering speeds (you shouldn't have 3rd gear traction issues is my assumption). If you spin you are losing momentum because if you lose that split second of peak torque production you are fighting a falling torque curve until the next gear and it repeats. The feeling is of a car that doesn't accelerate well because the peak was lost.
(Just as an aside, your acceleration g's follow your torque curve, so if it falls you feel that in terms of less g-force as rpm increases while torque decreases)
If you make more hp but the same or less torque you wouldn't have this feeling of lost acceleration coming off of a corner, leading to my next point... you need to make more hp, and with that, at higher rpm while limiting your low end torque to maximize grip. whatever is your acceptable traction limit in torque should be the amount of torque you try to produce at your rpm limit and also while raising your redline. If your car can manage 230wtq but not 280wtq, then make 230wtq flat until 7500rpm or higher. That way your car will be faster, take advantage of higher axle torque by holding gears longer, have more accelerative force against wind resistance and tire friction at speed because it is increasing power production with rpm as opposed to reduction power production with rpm as it is now, and reducing the necessity for higher longitudinal tire grip. I won't even get into how power production can actually provide more cornering grip/acceleration because that's an entirely different black art.
This takes me to tire width, technically a bigger contact patch has more grip, however without substantial aero that creates downforce most of that grip is only used at peaks of braking zones, acceleration, or in a corner. That split second peak uses all of the available grip potential but then the requirements lessen and the car is no longer forcing the tire to work at its limit and it can lose traction due to less weight being on that tire. You've felt that on a race track, when you dive-bomb a corner, right at the peak of grip trail braking to the apex and then as you pass that point of peak grip and before you transition to the throttle you start to understeer, even though the forces on your tires are less (you can watch this is you log g-forces)... that is because your contact patch is supporting less weight per sq in and thus is not able to grip as much as when maximum weight has been transferred. This is where a narrower tire will not have the same ultimate lateral grip but will have slightly more grip before and after that peak due to supporting more psi on the smaller contact patch. At the limit for longitudinal acceleration you would want to lengthen the contact patch, not widen it so a taller tire will have the same effect, both on acceleration and braking, so if you simply cannot put the power down effectively in more than 1 or 2 gears (if you had serious 3rd gear issues for example) a taller tire would be beneficial, but the width would have less effect.
The next advantage to a narrow tire is at high speeds where tire friction and the addition to frontal area and drag occurs. 4 225 width tires at 200mph are a massive improvement to acceleration abilities compared to 4 255 width or wider tires. This camry has a definite advantage in the 120-200mph range compared to similar powered cars with similar axle torque but much wider tires as an example. This is especially helpful to lower powered cars, so your car on a long straight for example would have the effect of gaining power and top end speed due to the friction/drag reduction
just remember that grip isn't absolute, and you don't need to have full grip all of the time, you just need to be able to manage it and make sure that a loss of grip isn't a total loss. Just like in one video of this camry doing some "acceleration testing" it blows the tires loose at 70mph and dances around a bit, but what you don't notice at first is that the engineers watching the test in the Hellcat behind were being walked away from by a car blowing its tires off... so even while traction was lost it was still accelerating faster than a Hellcat at WOT