What's needed for an sti trans swap in 09 wrx?
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ok, prepare to become very confused, sorry in advance.
Well the "R180 diff" and "differential" are the same thing, (diff=differential) so dont go buy two of the same thing, and also you might not need one anyhow. The main reason you need an STI r180 is it shares the same final drive ratio(3.60/1 vs. 3.54/1 that you have) as "most" of the the six speeds, I say most because some 6 speeds have have a 1.1/1 reduction gear that spits a 3.54 final drive ratio out to the rear diff while still having a 3.90 front diff. If you find on of these you can run it with your stock rear diff. Though these are the least common 6 speeds so its more likely you will find a 3:90 ratio 6-speed, in this case you can still run your rear diff/axle/hubs if you switch your rear diff gear to 3.90 from another 3.90 r160 rear end, or just swap in a R160 rear diff that already has 3.90 gears and an LSD, I got one off an older legacy for $200 a while ago, though I cant guarantee that the 08+ axles will plug into this.
Most people dont worry about changing the gears in the r180 since alot of 6-speed swaps come as a complete set with the rear diff/axles/hubs, and the r180 is bigger and stronger than the r160 so if your going for big power its a good idea (though I know alot of people with plenty of power on r160s doing fine) so if you find a sweet deal on just the 6 speed trans, a rear 3.90 gear swap would be the way i'd go, but you might just want to wait for a full driveline swap.
hope that made sense
Well the "R180 diff" and "differential" are the same thing, (diff=differential) so dont go buy two of the same thing, and also you might not need one anyhow. The main reason you need an STI r180 is it shares the same final drive ratio(3.60/1 vs. 3.54/1 that you have) as "most" of the the six speeds, I say most because some 6 speeds have have a 1.1/1 reduction gear that spits a 3.54 final drive ratio out to the rear diff while still having a 3.90 front diff. If you find on of these you can run it with your stock rear diff. Though these are the least common 6 speeds so its more likely you will find a 3:90 ratio 6-speed, in this case you can still run your rear diff/axle/hubs if you switch your rear diff gear to 3.90 from another 3.90 r160 rear end, or just swap in a R160 rear diff that already has 3.90 gears and an LSD, I got one off an older legacy for $200 a while ago, though I cant guarantee that the 08+ axles will plug into this.
Most people dont worry about changing the gears in the r180 since alot of 6-speed swaps come as a complete set with the rear diff/axles/hubs, and the r180 is bigger and stronger than the r160 so if your going for big power its a good idea (though I know alot of people with plenty of power on r160s doing fine) so if you find a sweet deal on just the 6 speed trans, a rear 3.90 gear swap would be the way i'd go, but you might just want to wait for a full driveline swap.
hope that made sense
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ok, prepare to become very confused, sorry in advance.
Well the "R180 diff" and "differential" are the same thing, (diff=differential) so dont go buy two of the same thing, and also you might not need one anyhow. The main reason you need an STI r180 is it shares the same final drive ratio(3.60/1 vs. 3.54/1 that you have) as "most" of the the six speeds, I say most because some 6 speeds have have a 1.1/1 reduction gear that spits a 3.54 final drive ratio out to the rear diff while still having a 3.90 front diff. If you find on of these you can run it with your stock rear diff. Though these are the least common 6 speeds so its more likely you will find a 3:90 ratio 6-speed, in this case you can still run your rear diff/axle/hubs if you switch your rear diff gear to 3.90 from another 3.90 r160 rear end, or just swap in a R160 rear diff that already has 3.90 gears and an LSD, I got one off an older legacy for $200 a while ago, though I cant guarantee that the 08+ axles will plug into this.
Most people dont worry about changing the gears in the r180 since alot of 6-speed swaps come as a complete set with the rear diff/axles/hubs, and the r180 is bigger and stronger than the r160 so if your going for big power its a good idea (though I know alot of people with plenty of power on r160s doing fine) so if you find a sweet deal on just the 6 speed trans, a rear 3.90 gear swap would be the way i'd go, but you might just want to wait for a full driveline swap.
hope that made sense
Well the "R180 diff" and "differential" are the same thing, (diff=differential) so dont go buy two of the same thing, and also you might not need one anyhow. The main reason you need an STI r180 is it shares the same final drive ratio(3.60/1 vs. 3.54/1 that you have) as "most" of the the six speeds, I say most because some 6 speeds have have a 1.1/1 reduction gear that spits a 3.54 final drive ratio out to the rear diff while still having a 3.90 front diff. If you find on of these you can run it with your stock rear diff. Though these are the least common 6 speeds so its more likely you will find a 3:90 ratio 6-speed, in this case you can still run your rear diff/axle/hubs if you switch your rear diff gear to 3.90 from another 3.90 r160 rear end, or just swap in a R160 rear diff that already has 3.90 gears and an LSD, I got one off an older legacy for $200 a while ago, though I cant guarantee that the 08+ axles will plug into this.
Most people dont worry about changing the gears in the r180 since alot of 6-speed swaps come as a complete set with the rear diff/axles/hubs, and the r180 is bigger and stronger than the r160 so if your going for big power its a good idea (though I know alot of people with plenty of power on r160s doing fine) so if you find a sweet deal on just the 6 speed trans, a rear 3.90 gear swap would be the way i'd go, but you might just want to wait for a full driveline swap.
hope that made sense

and I accidentally put different and differential lol just a typo not a total moron. No if the r160 diff will allow the use of my axles what would I need to do for my driveshaft? Would the sti driveshaft work? Or would I need to make a call to get a custom driveshaft? If so couldn't I just get an sti trans custom driveshaft and an r160 diff for this swap?
gauge cluster swap
is it possible to swap the gauge cluster too?
I am in the process of having full 6 speed swap installed on my 09 WRX and would do the STI gauge cluster as well if its compatible
I am in the process of having full 6 speed swap installed on my 09 WRX and would do the STI gauge cluster as well if its compatible
Not cool man. We were really hoping this thread would make seven years old this year. Only seven more months and six days.
Oh well, start the clock over again. See you all in 2024.
Oh well, start the clock over again. See you all in 2024.
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