Am I understanding, that the IS300 has the same engine as the 2011-2013 IS350 with 305hp? If so, why does it have 50 less HP? Is it just a detuned model, or are the heads/cam different perhaps?

 

It is in fact an identical v6 engine on the IS300 awd as it appears on the IS350 awd and rwd on same year models. The transmission on the awd IS300 and IS350 is also an identical 6 speed while the rwd IS350 has an 8 speed transmission. That 8 speed transmission is also on 2017 and forward 4 cylinder turbo IS300 rwd. IS300 v6 can be tuned up aftermarket to similar power as original on an IS350.

 

I hear 35 hp gains. Why not 50? Is it really just software causing a 50hp loss?

 

My understanding is that the v6 IS300 is just detuned via software, the IS350 is tuned more aggressively, therefore there isn’t too much left on the table for the aftermarket to turn it up. While the v6 IS300 has much more room for the aftermarket to modify and sell a map that ends up matching a tuned IS350. Technically they can both achieve the same power level. When I purchased my v6 IS300 I was actually looking for an IS350. But I test drove a 300 and felt it was plenty for what I do and I could keep $4-5,000 in my pocket. I ended up finding my car and negotiated a very good price. I then spend a few hundred on a vf tuner and a Loi tune, a few hundred on the F Sport intake and should be at IS350 power level with $3-4,000 still in my pocket. Either way I win and I’m stoaked.

 

Well, the actual numbers on a dyno will differ from the manufacturer's claims. I think the 35 is a wheel-horsepower number.