The 3.5 in the IS is from a different era though. almost 20 years ago type era. Same type of thing for my 4.0... The BMW engine you have has to be an up to date state of the art engine I assume?

 

Yeah, it's the B46 (in other countries, the B48 is used, but it's basically the same). It is a great engine. Compared to the EA888 I had in my VWs, the BMW engine has less turbo lag and more mid-range torque. However, I will say it seems to die off at higher RPMs more noticeably than the VW engine. No doubt it is an overall superior engine, especially with respect to fuel economy. Our lifetime average, that includes everything we've ever done, has been 31.3 MPG in the 330i. Really not bad for an over-3500-pound premium sedan that does 0-60 in the mid-5's! By contrast, my IS 350's lifetime average was 21.9 MPG last time I checked, so nearly a full 10 MPG less. Ouch! But, it does sound better and is smoother to drive around-town.

 

‘Feels that way maybe because it’s a 4 cylinder?

 

Well the EA888 was as well. I think it's just because BMW is using a very small turbo on their engine. Honestly, the EA888 made 228 horses versus 255 in the B46, so I know it's actually stronger. It's just power delivery is all in the mid-range RPM. This is much different from the 2GR in my IS where I have to rev it out. That car seems to come alive after about 4500 RPM or so.

 

‘Makes sense for the Lexus. The RPM peak is up high. What is the HP to HP between the BMW and the Lexus?

 

Honestly, these new turbo engines are deceiving. The IS has the higher power number but also weighs ~200 pounds more.

I am a nerd, so here's everything you would probably want to know about the engines themselves.

 

From my experience... they seem similar. I cruise at 75mph @ 2K ish. If I remember correctly, my Lexus vehicles were somewhere there too. Honda/Acura was much higher.

 

So right of the bat. More power in the 3.5. An extra cylinder. 255hp is not a lot power here. The final drive ratios would be good to know too. Great discussion and I love nerdy stuff

BMW? 3 series?

 

The BMW would win, it would produce more average power. Same type of thing comparing and EV to non-turbo HP, one produces more average power.

Sure the IS has more power....only at peak rpm for like 500rpm or so, at all other times the BMW has more. Plus you can tune it to have more HP period for only $1500

https://bmwtuning.co/b48-tuning-guide-300whp-for-1500/

No contest. It would make what the IS makes at peak at the crank at the wheels. To make the IS somewhat competitive these days you need the RR supercharger kit.

 

Aftermarket aside, modern BMWs are notoriously underrated to start with so the 330i's actual power output is probably closer to the Lexus than the official numbers say.

 

Yeah, thing probably puts down its "crank" number at the wheels as is. All the German stuff is like that, my German car stock is supposed to be 414 but it actually dynos 455 aka makes the crank number at the wheels. Now it gives a nice 570

 

Absolutely true. But the IS would most likely still be running strong after 200K, original head gasket, valves, and cylinders and trans if it was properly maintained. There are guys in the 2nd gen forum at 300K, everything original except the usual maint items, still running great. The IS's flame may not burn as bright, but it burns longer

EDIT

Stock 2nd Gen IS is around 286-287 at the wheels @6400 RPM

 

Yup, I don't like bringing tuning into the equation. I could supercharge the IS 350, and then what? It'd be 400+ horsepower at the wheels. But then, I could put a larger turbo on the Bimmer... it never ends. And I am sure the BMW's stock power is pretty much 250-260 wheel horsepower, which honestly is very close to the Lexus's wheel horsepower.

Regarding gear ratios, I have that, too.



The Lexus has taller ratios until you get to 5th gear. 4th and 5th are similarly close-ratio as the ZF's 3rd and 4th. Once you get up to highway speeds the Lexus and BMW are closer since the Lexus is going to stay in the power band a lot better. However, I think the BMW is still overall quicker. Not by much, but yes. And it'll definitely feel quicker due to the low-end grunt.

edit: And the above doesn't actually factor in the wheel size! Thankfully the two cars have very similar overall tire diameter.


If you want to really nerd out about these stats, I have an entire workbook: https://docs.google.com/spreadsheets...it?usp=sharing

 

if you check out MT. They have times and speeds for both. They are very close. I think the IS faster to 100mph by a tiny bit.

 

Car and Driver recorded similar numbers, with the IS350 accelerating faster to and beyond 100mph.