ISF with IS350 Diff...
08-25-12, 01:05 PM
#1
ISF with IS350 Diff...
So i just received my IS350 diff from Dv8tion388 yesterday and upon arrival i didn't waste no time installing it 
. 3hrs later everything was done with the help of my brother. The Install was straight forward and no axles had to be remove if you jack the car up high enough. First impression was WOW.. car pulled way faster thru gears compare to the stock diff. Down side is the car Max out at 150mph (didn't push it that fast yet, but had read about it) and car doesn't really down shift well in auto mode, but i did notice the car was getting better as i put more miles on it. Here a quick video of stock diff compare to is350 diff. In the video car is traveling up a incline. also the race in the video was between me and BoostFTW , but i had a little jump off the line. Both car had the same mod except for me which i had stock exhaust with cats delete and no muffler and he got a complete Joez. Will be doing another run with the new diff soon to see the different. Also i want to give a Big thanks to Dv8tion388, and Jeff Lange 
for answering any question and giving me tips to get this done properly... some of you might as why i did it, and flame for it, but it was just something i wanted to try out and after reading some discussion about it, it was convincing. plus i got the diff for a really good deal and labor was free because i did it. 
http://www.youtube.com/watch?v=5tYv2...ature=youtu.be
. 3hrs later everything was done with the help of my brother. The Install was straight forward and no axles had to be remove if you jack the car up high enough. First impression was WOW.. car pulled way faster thru gears compare to the stock diff. Down side is the car Max out at 150mph (didn't push it that fast yet, but had read about it) and car doesn't really down shift well in auto mode, but i did notice the car was getting better as i put more miles on it. Here a quick video of stock diff compare to is350 diff. In the video car is traveling up a incline. also the race in the video was between me and BoostFTW , but i had a little jump off the line. Both car had the same mod except for me which i had stock exhaust with cats delete and no muffler and he got a complete Joez. Will be doing another run with the new diff soon to see the different. Also i want to give a Big thanks to Dv8tion388, and Jeff Lange for answering any question and giving me tips to get this done properly... some of you might as why i did it, and flame for it, but it was just something i wanted to try out and after reading some discussion about it, it was convincing. plus i got the diff for a really good deal and labor was free because i did it. http://www.youtube.com/watch?v=5tYv2...ature=youtu.be
Last edited by obby; 08-28-12 at 10:38 AM.
Trending Topics
08-25-12, 02:24 PM
#9
^^^^Speedometer and odometer are fine, they come off the front wheels.
obby you gotta stop bouncing off the rev limiter - lol
I didn't realize the F dif was so much bigger than the 350 diff. You'll see how long it stands up. The new ratio will definitely give you a boost of the line, the only downside I can see is reliability - Maybe, and of course fuel mileage. IMHO, a max speed of 150MPH is no downside
Lou
obby you gotta stop bouncing off the rev limiter - lol
I didn't realize the F dif was so much bigger than the 350 diff. You'll see how long it stands up. The new ratio will definitely give you a boost of the line, the only downside I can see is reliability - Maybe, and of course fuel mileage. IMHO, a max speed of 150MPH is no downside
Lou
08-25-12, 02:26 PM
#11
^^^^Speedometer and odometer are fine, they come off the front wheels.
obby you gotta stop bouncing off the rev limiter - lol
I didn't realize the F dif was so much bigger than the 350 diff. You'll see how long it stands up. The new ratio will definitely give you a boost of the line, the only downside I can see is reliability - Maybe, and of course fuel mileage. IMHO, a max speed of 150MPH is no downside
Lou
obby you gotta stop bouncing off the rev limiter - lol
I didn't realize the F dif was so much bigger than the 350 diff. You'll see how long it stands up. The new ratio will definitely give you a boost of the line, the only downside I can see is reliability - Maybe, and of course fuel mileage. IMHO, a max speed of 150MPH is no downside
Lou
08-25-12, 03:11 PM
#14
The IS350 and IS-F differentials are the same size (208mm). The difference is the IS F has extra cooling fins on the exterior of the case. I would have probably used the IS F rear cover on the IS350 differential if I did the swap just for good measure, though your speed is limited now anyway 
.
As for the speed sensor, it's based on the speed of the wheels from the ABS speed sensor, I believe it is mostly (if not entirely) rear wheel biased, not front wheel. (If you spin your rear wheels, your speedometer will go up. That being said, since it is wheel based, changing gearing will not affect its accuracy.
I probably wouldn't have wanted to do this much gearing change just because of the increased RPM's all the time, but still cool I guess. I'd like to get a 4.1 gearset for my IS250.
Jeff
.As for the speed sensor, it's based on the speed of the wheels from the ABS speed sensor, I believe it is mostly (if not entirely) rear wheel biased, not front wheel. (If you spin your rear wheels, your speedometer will go up. That being said, since it is wheel based, changing gearing will not affect its accuracy.
I probably wouldn't have wanted to do this much gearing change just because of the increased RPM's all the time, but still cool I guess
. I'd like to get a 4.1 gearset for my IS250.Jeff
Last edited by Jeff Lange; 08-25-12 at 03:15 PM.