STi launch
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Nope. Other way around. The early STis were 35 front, 65 rear, such that the torque distribution matched the weight distribution on a hard launch. But 65% rear is a bit much at corner exit and lots of people crashed, so they backed it off to 42/58 after two or three years.
Our center diff is a spider type, so it has to be 50/50. Thus, we are more dependent on the ACD to lock and send more torque to the rear on a hard launch to avoid front-wheel spin. If you launch a powerful Mitsu on drag tires, without some reprogramming of the ACD, you will spin the fronts a bit.
Could be worse. Could be in a powerful 2G DSM with the silly VC limited-slip center. I could spin the fronts on any tires in that car. Cusco makes a 35/65 center for DSMs, but it was expensive and I sold the car, instead.
Our center diff is a spider type, so it has to be 50/50. Thus, we are more dependent on the ACD to lock and send more torque to the rear on a hard launch to avoid front-wheel spin. If you launch a powerful Mitsu on drag tires, without some reprogramming of the ACD, you will spin the fronts a bit.
Could be worse. Could be in a powerful 2G DSM with the silly VC limited-slip center. I could spin the fronts on any tires in that car. Cusco makes a 35/65 center for DSMs, but it was expensive and I sold the car, instead.
Yeah, but we're talking about launching and the best torque distribution for that is whatever matches the weight distribution when launching. An STi with decent tires can launch at about .85g which will shift the weight distribution to about something between 40/60 and 35/65, so a rear-biased center diff is best.
As to what's best for powering out of a corner, that depends a lot on the front diff. A good front diff, like a helical (which is what an X has), can use power to rotate the car because the front wheels are turned. Add in the AYC and Xs leave corners almost too well, as anyone who came from an understeering pig can tell you, as it takes a while to get used to how well the car rotates under power. Too much right foot in a tight corner and the car climbs the inside curb.
As to non-ACD AWDs, the biggest problem with the VC center diff in older Mitsus is how difficult they are to predict. VCs are not only non-linear, but are highly dependent on previous conditions. VCs grab more when hot (which is why is takes a few minutes to burn one out if a pinhead tows your 2G DSM with two wheels on the ground). If the VC is already hot when you floor it, it will grab sooner and harder, making it worth it. If the VC is cold, flooring it at corner exit will cause terrible push, unless you have a really good front diff and lots of inside-front grip.
For launching, a VC center will almost definitely not be able to send enough torque to the rear. That's the other problem with VCs; they simply can't lock hard enough. That's why most serious drag-racers with older Evos and DSMs just weld the center into a spool.
As to what's best for powering out of a corner, that depends a lot on the front diff. A good front diff, like a helical (which is what an X has), can use power to rotate the car because the front wheels are turned. Add in the AYC and Xs leave corners almost too well, as anyone who came from an understeering pig can tell you, as it takes a while to get used to how well the car rotates under power. Too much right foot in a tight corner and the car climbs the inside curb.
As to non-ACD AWDs, the biggest problem with the VC center diff in older Mitsus is how difficult they are to predict. VCs are not only non-linear, but are highly dependent on previous conditions. VCs grab more when hot (which is why is takes a few minutes to burn one out if a pinhead tows your 2G DSM with two wheels on the ground). If the VC is already hot when you floor it, it will grab sooner and harder, making it worth it. If the VC is cold, flooring it at corner exit will cause terrible push, unless you have a really good front diff and lots of inside-front grip.
For launching, a VC center will almost definitely not be able to send enough torque to the rear. That's the other problem with VCs; they simply can't lock hard enough. That's why most serious drag-racers with older Evos and DSMs just weld the center into a spool.
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Yeah, but we're talking about launching and the best torque distribution for that is whatever matches the weight distribution when launching. An STi with decent tires can launch at about .85g which will shift the weight distribution to about something between 40/60 and 35/65, so a rear-biased center diff is best.
As to what's best for powering out of a corner, that depends a lot on the front diff. A good front diff, like a helical (which is what an X has), can use power to rotate the car because the front wheels are turned. Add in the AYC and Xs leave corners almost too well, as anyone who came from an understeering pig can tell you, as it takes a while to get used to how well the car rotates under power. Too much right foot in a tight corner and the car climbs the inside curb.
As to non-ACD AWDs, the biggest problem with the VC center diff in older Mitsus is how difficult they are to predict. VCs are not only non-linear, but are highly dependent on previous conditions. VCs grab more when hot (which is why is takes a few minutes to burn one out if a pinhead tows your 2G DSM with two wheels on the ground). If the VC is already hot when you floor it, it will grab sooner and harder, making it worth it. If the VC is cold, flooring it at corner exit will cause terrible push, unless you have a really good front diff and lots of inside-front grip.
For launching, a VC center will almost definitely not be able to send enough torque to the rear. That's the other problem with VCs; they simply can't lock hard enough. That's why most serious drag-racers with older Evos and DSMs just weld the center into a spool.
As to what's best for powering out of a corner, that depends a lot on the front diff. A good front diff, like a helical (which is what an X has), can use power to rotate the car because the front wheels are turned. Add in the AYC and Xs leave corners almost too well, as anyone who came from an understeering pig can tell you, as it takes a while to get used to how well the car rotates under power. Too much right foot in a tight corner and the car climbs the inside curb.
As to non-ACD AWDs, the biggest problem with the VC center diff in older Mitsus is how difficult they are to predict. VCs are not only non-linear, but are highly dependent on previous conditions. VCs grab more when hot (which is why is takes a few minutes to burn one out if a pinhead tows your 2G DSM with two wheels on the ground). If the VC is already hot when you floor it, it will grab sooner and harder, making it worth it. If the VC is cold, flooring it at corner exit will cause terrible push, unless you have a really good front diff and lots of inside-front grip.
For launching, a VC center will almost definitely not be able to send enough torque to the rear. That's the other problem with VCs; they simply can't lock hard enough. That's why most serious drag-racers with older Evos and DSMs just weld the center into a spool.
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