Best OEM final drive for 5 speed T25/2554 DD/AutoX/HPDE
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So, my car is daily driven, and will be used for 4 Autox a year or so, and HPDE like twice a year. 5-speed, and guestimated final numbers should be a round ~225ft-lb, 235hp.
I'm considering swapping my 4.30 to a 3.90 to have a little longer in each gear. I have an offer to trade my diff flat out, though mine has 72k on it, and the mileage on the 3.90 is unknown. Otherwise, his asking price is $500 without the carrier. Looking to hear from people on both sides, as most people I've asked their opinions are running a 4.10.
My fear is, as far as enjoying the turbo DD, I'll lose some of that *back of your seat* feeling at this power level. I expected fuel economy gains on the highway, but in reality, I will only be going from 4080rpm@80mph to 3709rpm. So, not really all that much of a change.
AutoX I think will be benefited by having a higher top speed in 2nd gear.
I can't speak for HPDE, as my first event is in May.
So, Tl;Dr: What is your ideal final drive for a T25/2554 setup with a 5 speed, that will be daily driven, with bimonthly autocross time, and semiannual HPDE?
I'm considering swapping my 4.30 to a 3.90 to have a little longer in each gear. I have an offer to trade my diff flat out, though mine has 72k on it, and the mileage on the 3.90 is unknown. Otherwise, his asking price is $500 without the carrier. Looking to hear from people on both sides, as most people I've asked their opinions are running a 4.10.
My fear is, as far as enjoying the turbo DD, I'll lose some of that *back of your seat* feeling at this power level. I expected fuel economy gains on the highway, but in reality, I will only be going from 4080rpm@80mph to 3709rpm. So, not really all that much of a change.
AutoX I think will be benefited by having a higher top speed in 2nd gear.
I can't speak for HPDE, as my first event is in May.
So, Tl;Dr: What is your ideal final drive for a T25/2554 setup with a 5 speed, that will be daily driven, with bimonthly autocross time, and semiannual HPDE?
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