ayu910

if not for introduction of 335i...I will go with the is350 for sure. for almost the same price I can get 6sp manual, twin turbo with solid chassis and that is hard to pass.

335i can have 300 lb/tq from 1500rpm so I think turbo leg shouldn't be a major issue. as I reacall compression ratio of this car is around 11:1 thanks to direct injection technology.

I just wish Totota had the DI when I had my 2JZ...for sure will help to spool up my T-78 a lot quicker

15951

Turbo wars aside, I reject the assertion in a previous post that the Bimmer 3.0 with turbo is more "elegant" than the Lexus 3.5 making the same horsepower normally aspirated. What a load...if the roles were reversed, then there'd be text on this forum about Lexus not having the cajones to step up to the plate with a bigger NA engine. As it stands, we've got more to start with, and more to mod IMO.

Maybe I live my life in a vacuum, but in my world, 99% of the population DOESN'T autocross, or spend their weekends at the track running quarter miles. For everyone other than hardcore enthusiasts and auto journalists, the IS350 is a better daily driver, period. You can put as much subjective "soul" into a Bimmer as you want, but as long as the interior sucks and it's only fun to drive at the limit, I'll take the Lexus all day long.

Those of you regretting spending the money on a Lexus will feel much better about your purchase in a few years when you're driving by the dealer's service garage without needing to stop and get something repaired. Bimmers have a wonderful following, and I'm sure they're great "drivers'" cars, but their reliability sucks and the interior design (the part of the car I see most of the time) is reprehensible for what they're charging. In my book, those are drawbacks I just can't live with.

adrianchew

Ok my intent wasn't to start up a turbo/non-turbo war, but some of the comments I've seen about the IS makes me go ?

Some say the IS weighs too much - its like only 100lbs more than a 330i... that's not a big margin. And its probably my bad for trying to compare handling of the IS to BMW, but in general I still can't get a real feel - hearing people here it seems to range that some thing the IS is like jello on wheels, and others say totally fine?

Its got to be firmer than say a Mercedes setup? I know its a bit of a bad comparison FWD/RWD, but some here have Acuras in their garage too... IS is firmer than a TL, more like a TSX? Or more like a TL? And please say if you have the sport suspension on the IS or not in the comparisons.

ff_

That may or may not be true (I'm by no means a turbo expert), but I firmly believe that packaging was probably the primary motivating factor, as there is already very little room under the 3 series hood in NA form.


Well, the 330i itself is a fat pig... so 100 pounds more than fat pig is an even fatter pig. I see no reason to give one carmaker an easy "out" simply because they're only a little heavier than some other car. Fat is fat. Period.

roubaixpro

I found an article on the BMW 335i with some quotes from the article below. It sounds like the 335i has closer to 350 hp vs. the listed 300 hp based on dyno runs. Anyway, I briefly saw one driving on the streets of downtown San Francisco and the car looked gorgeous. I assume it was a dealer preview car because it is not on sale yet. Anyway, I own an IS350 and have no regrets. An equally equipped 335i will cost a lot more than an IS350.


"A few quick taps on our trusty calculator shows that this engine is likely putting out closer to 350 hp and 360 lb-ft of torque."

"Don coaxed the 335i to 60 mph in 5.1 seconds--only 0.3 seconds slower than the M3. The 335i covered the quarter-mile in 13.6 seconds @ 104 mph--again, only 0.2 seconds and 1 mph behind the M3."

http://www.automobilemag.com/feature...i_dynamometer/

Lets Drive

iTrader: (3)

Well, there are advantages, just not always in power. Seq. twin systems can be very complex, not very durable due to the complexity, and overall just a damn headache when it comes to maintanence- I can't stand trying to diagnose and replace vac. hoses and solenoids (I personally kept my stock sequentials for response, but the transition from primary to secondary can be a kicker at times). I think BMW went for a balance with this vehicle, and selected this setup to be well within what they wanted for torque and response, but also a nice peak hp, while not being overly complex and costly, which is the goal of any good system. The obvious sacrifice in power delivery would come in the upper range, but driveability for most other circumstances is well catered to...plus, marketing two turbos works better than one.

That very much depends on the design of the turbo, not its physical size by default. The main reasons BMW chose to use parallel turbos, are due to fit, cost and simplicity, while response provides its benefits.

SolaraToIS

I'll second that

4TehNguyen

iTrader: (1)

With these new variable flow turbos like on the RDX and 911 turbo, you can control the exhaust gas valve intake to the turbo, closing it will make the exhaust gas come in faster and hit the turbines with more momentum so it can spool up and provide boost pressures in earlier rpms. If its early enough the car will drive like a N/A car but with the power of a turbo. 911 turbo gets 450 ft lbs at 1950 rpm, unbelievable.

the 335 stock turbos are too small you can tell because power dies off really early at 4k rpm (doesnt flow enough air to maintain boost pressures at high rpms). But of course you have less lag with these smaller ones. Upgrading the size of the turbos youll greatly improve the mid to high range power but increas some lag in the low rpms, basically the dyno would probably shift over 1000 rpm or so to the right, but the torque curve will maintain itself instead of dropping off. 335 will be killer when that happens

Personally after reading some catastrophic engine problems with the M3, and now the have turbo chargers on their i6 im skeptical on how long the 335 engine will last.

Mike_TX

I'm one of those with a TL in the garage, Adrian. And I wish I could directly compare the two, but they're just such different cars and are quite a bit different in their "feel".

My IS350 is a non-Sport, and my '06 TL has the stock suspension as well. OVERALL, the TL's ride is a little gentler on the bones ... that is, it doesn't transmit jarring thuds to the cabin when you hit a sudden, abrupt pavement irregularity. The IS can jar you a bit more if you plow into a pothole, for example.

My IS (and note there's a lot of disagreement about this) tends to serve up a lot of up-and-down jiggles on what seem to be smooth roads. Then, if I get off onto roads with lots of ripples and dips, it can really slosh me around. It's not like there isn't any suspension under there - it's just a busy, somewhat jerky ride. The TL is pretty serene over both these same roads.

The TL has a fairly firmish suspension, but manages to deliver a pleasant ride under most circumstances. I had a TSX as a loaner the other day, and the TL's ride is quite a bit better. The IS does have a small amount of initial body lean when you make a quick transition (like a sharp turning maneuver), but then it gets over it quickly and tightens right up. The TL, OTOH, feels a little mushier in quick moves because of the heavy nose and slightly softer springing.

The biggest issue with the handling IMO is the steering, which is too light and doesn't tug back at you when in a turn to signal what's going on at the tires.

Now, I've "fixed" my IS to a large degree by dropping the tire pressure, but otherwise I feel its suspension components are just basically fighting with themselves. I know the Lexus engineers went to a lot of trouble tuning this suspension, but I guess it's just lost on me. I don't understand why a car this heavy can't be made to smother ripples and small irregularities better while still keeping the body under control in turns and corners.

That said, it's not a total loss by any means. I still like my car, and I'll continue to enjoy driving it. So my advice to you - or anyone else looking at this car - is to drive it a lot first. test it on different roads, not just the smooth ones around the dealership the salesguys like to take you on. Then make up your own mind.
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4TehNguyen

iTrader: (1)

low pro 18" tires and more stiff suspension will make thuds, even on my dads M package 740 it still does it, but the sidewalls are thicker than an IS, or maybe its because im desenstized driving on 215/35/18 tires, I've had my share of thuds, so Ill be able to handle any thuds on an IS

Koz

The reason BMW went turbo is simply because they needed to make more power to take away the power advantage of the IS. Let’s face it, the power difference was severe. 1 full second to 60 is a LIFETIME. Who would have guessed that Lexus, of all manufactures, would have developed a naturally aspirated fire breather? It’s been said that “Power is not everything” but the people who say it, are the people with less power. In the real world, as a daily driver power is the most important advantage. When you can’t match the power, some people will start pointing at some other advantage they may have regardless of how small it may be. The handling difference, on the street it is not anywhere near the difference, as the power. And the road-feel, please! BMW was apparently caught with there pants down and they know this, that’s why they are adding the turbos, or they would have had a larger displacement engine ready to make the power they needed. The only quick solution was to throw on a power adder. If I’m not mistaken BMW had always prided themselves for not having to use power adders. I personally think BMW has turned in the wrong direction by adding all that complexity to their vehicle when they already had more then their share of high tech reliability issues.

Koz

ISbb

Sorry forgot to tell you that I love my IS so much... One thing let to let you know that A Lexus is a Lexus... Do you compare to BMW and any other european car... The reason I buy IS is it is so differents than BMW 3 and Benz C-Class out there on the road... and all sort of techology on IS is much better than BMW 3... I am not saying BMW 3 is a bad car just for myself I choose IS over the BMW 3 the look the feeling are all matter...

Lets Drive

iTrader: (3)

It would be a slight contradiction, as BMW has utilized turbos before.

Koz

As far as I know BMW only made a few turbos in the 70s (less then 2000). I recall an article where someone from BMW was making a point about how BMW doesn't have to use turbos to be the performance leader.

Koz

Cornellian

The Performance of a Turbo and the engine does not ONLY depend on the heat. However, it depends more on the DENSITY of air and air/fuel ratio that is coming in to the system. And the latter depends on the area of the intake hole. So, the more AREA you have the more AIR you have --> giving you a more CONDENSE air and better combustion process and raising the overall temperature inside the engine/turbo. What you guys said about exhaust driving the turbos is absolutely correct, BUT the DENSER air plays a major role in raising power because P is proportional to mass flow, which is proportional to the density.

Now, I am not sure but the reason why BMW chose to have 2 turbo's instead of 1 would probably be due to the fact that one single turbo will be massive and will take up more room. Secondly, depending on where you put that massive turbo will generate more vibrations in the vehicle as supposed to 2 turbos, which if oriented correctly will have less vibrations.