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My ride
- Thread starter Sankekur
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Crash_Nemesis
///Member
I wonder what a 3.46 diff would do to my car. hmmmmmm
Sankekur
///Member
Thanks guys.
@crash_nemesis: You would probably need to change to a medical aid that give more cover for things like neck injuries :rollsmile:
What is the standard ratio in the 323i? As you might want to go for something a bit less aggressive than a 3.46 diff, cause you have a supercharger to give you more than enough torque, so you'd want a bit more legs on the car.
Oh and it can also happen that you will experience less traction issues in general with a shorter ratio diff.
@Andy: That is still a secret, what I will say is they 18" and are wheels that was available on the e46 and an accessory (not an extra), I should hopefully have them by this coming week or next week :rollsmile:
@crash_nemesis: You would probably need to change to a medical aid that give more cover for things like neck injuries :rollsmile:
What is the standard ratio in the 323i? As you might want to go for something a bit less aggressive than a 3.46 diff, cause you have a supercharger to give you more than enough torque, so you'd want a bit more legs on the car.
Oh and it can also happen that you will experience less traction issues in general with a shorter ratio diff.
@Andy: That is still a secret, what I will say is they 18" and are wheels that was available on the e46 and an accessory (not an extra), I should hopefully have them by this coming week or next week :rollsmile:
sank those rims look awesome on you car 
the 323i has a 3.07 diff...
the 330i with a 3.38 diff has about 0.6% less torque at the wheels than this 323sc...
you gained about 15% more torque when you changed to 3.38...
the 323sc with a 3.38 or 3.46 ratio will have about 15% more torque at the wheels than you currently have on your 330i with the 3.38 diff
So what you think sank traction issues?
the 323i has a 3.07 diff...
the 330i with a 3.38 diff has about 0.6% less torque at the wheels than this 323sc...
you gained about 15% more torque when you changed to 3.38...
the 323sc with a 3.38 or 3.46 ratio will have about 15% more torque at the wheels than you currently have on your 330i with the 3.38 diff
So what you think sank traction issues?
Sankekur
///Member
@Wykid: Yeah I will be looking at spacers with new wheels, but I am not sure how flush I would be able to get them without rubbing, and there is not much the arches can be rolled ATM.
@herr: lol :rollsmile:, just remember our deal, I slam my car, you paint your 18" wheels pink :grin:
@moranor: The strange thing about traction when going for a shorter ratio diff is that you would expect less traction due to more torque, but it would seem that the reduced speed of rotation of the wheels has a bigger effect on traction than the increased torque.
(This is not out of my personal experience, but what I have heard from people, have not tried this out myself :rollsmile: )
@herr: lol :rollsmile:, just remember our deal, I slam my car, you paint your 18" wheels pink :grin:
@moranor: The strange thing about traction when going for a shorter ratio diff is that you would expect less traction due to more torque, but it would seem that the reduced speed of rotation of the wheels has a bigger effect on traction than the increased torque.
(This is not out of my personal experience, but what I have heard from people, have not tried this out myself :rollsmile: )
i dont quite get what you saying about the speed :fencelook: maybe i need more coffee...
still not getting this even after more coffee
do you mean because of the increased engine braking you lose more traction than you would with increasing engine torque of the same amount? i see this as a good thing because it give you more control and makes the car more dynamic :rollsmile:
do you mean because of the increased engine braking you lose more traction than you would with increasing engine torque of the same amount? i see this as a good thing because it give you more control and makes the car more dynamic :rollsmile:
moranor said:still not getting this even after more coffee
do you mean because of the increased engine braking you lose more traction than you would with increasing engine torque bu the same amount? i see this as a good thing because it give you more control and makes the car more dynamic :rollsmile:
now i need more coffee:roflol:
Philip Foglar
///Member
She is looking hotter than ever!! Especially with the addition of the new 'stopping power devices'!!! :thumbs:
Sankekur
///Member
Thanks guys :ty:
@moranor: What I am saying is that it would seem that losing traction is based on two things (probably among others) torque at the wheels and the wheel speed and it would seem that the wheel speed has a greater effect.
So if you rev the engine to a certain RPM for pull-away you will have x torque and y wheel speed, now you change the diff ratio by 15% so it means at the same rpm you will have 1.15x torque and 0.85y wheel speed, so now if the wheel speed has a greater effect you will have better (slightly) due to the torque and wheel speed changing by the same factor.
Though I do not claim full understanding of this, this is just I made this make sense to me - the fact that people I have spoken to that have fitted shorter ratio diffs and then find that they have better traction.
@moranor: What I am saying is that it would seem that losing traction is based on two things (probably among others) torque at the wheels and the wheel speed and it would seem that the wheel speed has a greater effect.
So if you rev the engine to a certain RPM for pull-away you will have x torque and y wheel speed, now you change the diff ratio by 15% so it means at the same rpm you will have 1.15x torque and 0.85y wheel speed, so now if the wheel speed has a greater effect you will have better (slightly) due to the torque and wheel speed changing by the same factor.
Though I do not claim full understanding of this, this is just I made this make sense to me - the fact that people I have spoken to that have fitted shorter ratio diffs and then find that they have better traction.
now im getting it this would enplane why there is a definite peak in performance with gear ratio... running simulations on my car it seems to be 3.64 any shorter and i dont seem to gain any acceleration even though i still gain torque...
it must be because im still dealing with the same max engine RPM so the wheel speed is limited...
I will experiment with higher RPM to see if this is true...
maybe the coffee only kicked in now :rollsmile:
this would enplane why there is a definite peak in performance with gear ratio... running simulations on my car it seems to be 3.64 any shorter and i dont seem to gain any acceleration even though i still gain torque...it must be because im still dealing with the same max engine RPM so the wheel speed is limited...
I will experiment with higher RPM to see if this is true...
maybe the coffee only kicked in now :rollsmile:
Sankekur
///Member
Glad to hear that :rollsmile:
Might also have to do with maximum response of the engine and gear changes that might be hampering acceleration even though torque is increased.
Just a little bit of an aside in terms of the diff swop, I would definitely recommend the 3.38 diff that I have done for anyone with a 330i and a 6 speed gearbox, it really makes the car feel like its supposed to.
Might also have to do with maximum response of the engine and gear changes that might be hampering acceleration even though torque is increased.
Just a little bit of an aside in terms of the diff swop, I would definitely recommend the 3.38 diff that I have done for anyone with a 330i and a 6 speed gearbox, it really makes the car feel like its supposed to.
Philip Foglar
///Member
I think I am understanding what you mean and if so the best way to explain, a shorter ratio is able to then make better use of the engine's lower end torque so that more response and control of traction can be obtained without spinning as easy due to the higher rev power band. Kind of like how a diesel engine's response in most cases beats a petrol when off-roading - easier to control the diesel engine and avoid spinning which could land you stuck in the sand/mud...
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