Lexus Is-f W/ 350 Diff

richeerich03 · 07-24-2013, 10:54 AM

pretty cool video..

wisesoul · 07-24-2013, 04:06 PM

IS350 has way shorter final drive, that thing pulled way harder as a result. If I remember correctly, they share the same diff but ISF has different cooling hardware. Probably cheaper than an LSD with new gearing though.

NemesisX · 07-24-2013, 05:54 PM

Yeah the gear ratios on the IS350 are ridiculously aggressive, particularly down low.

I actually don't think this swap is worth it. 416 HP with IS350's gearing is way too aggressive for the first couple of gears. I'm not surprised that he couldn't get any traction. If you can't get traction, why even bother?

The ISF's stock gearing was perfect because it allowed it to pull hard enough down low and hard up top.

Now, it'll pull even harder down low if you had street-illegal drag radials or something.

ToothDoc · 07-24-2013, 10:18 PM

It's pointless except at a dragstrip with really good drag radials. If you graph speed vs. power, the advantage is only for the first 2 seconds and after that, it's back and forth between the short ratio and the stock ratio. The stock ratio is ALREADY very short with 2nd gear topping out at barely over 60 mph.

07-24-2013, 10:54 AM	#1
richeerich03 Captain 168 Rep 877 Posts Drives: E90 Join Date: Jun 2007 Location: Santa Clarita iTrader: (0) Garage List 2006 E90 330i [0.00]	Lexus Is-f W/ 350 Diff pretty cool video.. __________________
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07-24-2013, 04:06 PM	#2
wisesoul Savoir Faire 83 Rep 1,771 Posts Drives: 2013 BMW M5 Join Date: Aug 2010 Location: Los Angeles, Ca iTrader: (0)	IS350 has way shorter final drive, that thing pulled way harder as a result. If I remember correctly, they share the same diff but ISF has different cooling hardware. Probably cheaper than an LSD with new gearing though. __________________ Current: Alpine White F10 M5\|H&R springs\|12mm/10mm spacers\|Eisenmann Race Sold:Imola Yellow RS4-KW V3\|MTM 10mm spacers\|Hotchkis rear sway bar\|APR Stage 1\|Milltek Catless\|RNS-E\|Euro RS4 Flat bottom Steering Wheel Sold:E46 323i
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07-24-2013, 05:54 PM	#3
NemesisX Captain 321 Rep 905 Posts Drives: '19 Infiniti Q60S Join Date: Jul 2009 Location: TX iTrader: (0)	Yeah the gear ratios on the IS350 are ridiculously aggressive, particularly down low. I actually don't think this swap is worth it. 416 HP with IS350's gearing is way too aggressive for the first couple of gears. I'm not surprised that he couldn't get any traction. If you can't get traction, why even bother? The ISF's stock gearing was perfect because it allowed it to pull hard enough down low and hard up top. Now, it'll pull even harder down low if you had street-illegal drag radials or something.
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07-24-2013, 10:18 PM	#4
ToothDoc Second Lieutenant 5 Rep 241 Posts Drives: 997.2 TTS, CLA 45 AMG Join Date: Aug 2007 Location: Chicagoland iTrader: (0)	It's pointless except at a dragstrip with really good drag radials. If you graph speed vs. power, the advantage is only for the first 2 seconds and after that, it's back and forth between the short ratio and the stock ratio. The stock ratio is ALREADY very short with 2nd gear topping out at barely over 60 mph.
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