DaveB: I would assume some of the 05 new weight comes from the upgraded interior but only counts for what about 30-40lbs? Then there is the new tires and rims but that shouldnt be more that 20lbs total at most since from my understading the 19's weight closely to what the sport 18's did. The other weight addons I am not sure, I am not sure what. What the weight of the 05 auto sedan with the sports package?

 

I think weight is a big factor. I'm sure the 05 is heavier than the 03 - cars typically gain weight with age as improvements are made. It also depends what options each test car has, if the gearing was changed, size of the wheels, and how sticky the tires are. Infiniti might of spread out the gears more to help fuel economy.

 

Actually Car and Driver tested the 2003 Coupe with a best of 0-60 in 5.5 and the quarter mile passing in 14.2@100
See Here

Although "magazine racing" to me is just a guideline to the performance abilities of a vehicle, THIS LINK will further give you ideas of the potential of other cars.

In regards to tenths, if I remember correctly a couple tenths through the traps at our trap speed is at least of couple of car lengths. So I'd venture to say that those tenths do matter if you go to the track.

By the way, good info DaveB and a nice thread guys. AC

 

Fyi everyone the 2005 6spd Sedan also comes stock with 18" Rims so testing is not equal vs 03/04 with 16/17" rims

 

Good point, and excellent post everyone.

I remember back in '03, when I was researching cars for my eventual purchase (chose the "G"!), I read somewhere that Infiniti engineers had tried rim sizes from 15" to 19" on the "G" during it's testing and development, and had ascertained that the 17" wheel size was the "optimal" size for best all around performance, with slightly quicker 0-60 and 1/4 mile times coming with the 15" & 16" rims (due to the rotational mass issues fully discussed elsewhere), but cornering and ride quality suffering slightly. Cornering was best with the larger rims, but again, acceleration out of the corners suffered a little, so the 17" rims were eventually determined to be the best overall compromise (which is why even the "sport" package rims were only 17"s in '03 & '04).

Popularity & "bling" factor of larger rims eventually gave rise to the 18" & 19" rims available now (consumer demand & the marketing department once again overcomes engineering knowledge & prowess ). It all makes sense to me, and is further bolstered by some of our members here testifying that they have obtained their best 1/4mile times with 16" rims.

What the engineering department giveth (extra horsepower), the marketing department taketh away (large rims with greater rotational mass, further from the driven point at the center of the rim, and maybe even heavier).

My $0.01

 

Great write up Dbarnes,
As I also remember long time ago in a MT magazine, it did a test of an EG6 civic with rims size varied from 14, 15, and 16. The rims are the same aftermarket brand/model and so the weight will increase proportionally. The best acceleration, braking, and cornering were best by using 15" rims. That is why many track racers who race EG 6 used 15 instead of larger sizes.
I am sure that engineering in car manufacturer or in their racing dept studied varieties of combination to make car perform the best but then like you said, marketing dept has other say to it.
If I remember that someone dynoed an 05 6mt coupe w/ no mods and the number is approx 240ish. And the 03/04 6mt w/ no mods are around 225. If the 03/04 motor is down average of 15 hp at the wheel with the mechanical loss of approx 17 to 18% from the crank, 03/04 6mt should be making around 280 bhp. That pretty much proves that Infiniti did advertise the 03/04 6mt with lower horsepower. I think it's all about marketing scheme.

There is no doubt that 05 is turning out more power but I think the acceleration is offset by the additional weight.

 

Excellent post. In today's market wheel size on higher end cars is largely dictated by market demand, not performance. Big rims and short wide tires don't necessarily mean better handling. Dodge even admits the Viper is a faster and better handling car on smaller 16" rims and NARROWER tires. BUT who would want narrow tire 16s on their badass Viper? It just wouldn't look right.

I'm in the minority here, but I think the 17" Sport wheels are the perfect size for the G sedan once you've got a little drop. I too believe they're the perfect compromise between handling and acceleration. I wish the tire/rim combo wasn't so heavy though. 52lbs is a bit heavy. I had lightweight 17s on my Maxima and the entire combo weighed 41lbs. I may just add light 17s to the G. That way I'll get even better handling, braking, acceleration, and improved ride quality with absolutely no penalty.

I'm sure the 18s slow the 05 down a little bit, but I don't think it's terribly severe seeing that the 18s are relatively light...though the rotation weight is further from the hub which is what kills power. Last Fall I did a test with my Maxima. I made 3 passes with the stock 215/60R15 38lb tire/rim combo and then 3 passes with my aftermaket 235/45R17 41lb tire/rim combo. With the 15s, the car went 14.4-14.5@97mph with 2.2 60 foots. With the 17s it went 14.5-14.6@96mph with 2.2 60 foots. Roughly .1 and 1mph was sucked out by the larger, wider, and heavier 17" combo.

I'll admit that 19s on a G look damn good, but way too much power is sucked out trying to spin those things. I really don't like to add mods that negatively impact the way the car performs. That's just me though and I'm in the minority.

 

DaveB:

I'm with you in that minority, Dave, who feels that performance matters more than looks.

It could be the fact that I'm 47 years old now (who is that old fart who lives in my mirror??), and what with a little extra weight and a little less hair, etc., I'm finding that performance matters more than looks in most areas of life

Good post with many excellent points and comments - love hangin' out with knowledgeable car guys (and gals, as long as performance means more than looks )

 

One test does not mean the 03-04 cars are as quick. It is almost impossible that the first 05 car tested would be the fastest ever and there are tests on the earlier cars that are MUCH slower than a 14.2. This C & D comparison they dont give out the full track data except to say that the Acura TL in the group ran 5.8 seconds 0-60 "a half second quicker than the G35" which was a 6M http://www.caranddriver.com/article....&page_number=8
A small increase in the weight is not going to eat up 38hp and I highly doubt they set out to make the new model slower in this ultra competitive class. The new G has about the same power to weight ratio as the old 300zx turbo with better aerodynamics. I expect high 13s with a good driver. It will be very interesting to see how it matches against the new 3 Series.
JB Car tested the 03 http://www.jbskyline.net/Sedans/Specs/

 

"A small increase in the weight is not going to eat up 38hp and I highly doubt they set out to make the new model slower in this ultra competitive class. The new G has about the same power to weight ratio as the old 300zx turbo with better aerodynamics"

the problem is that the new engines don't have the 38hp increase through out the powerband. Most testers agree that the new engine actually losses bottom range power, but picks up at the top end.

 

I am looking in motortrend's website i cant find that link testing 2005 G35.
Can someone help me?

 

I don't think it'll be on the website till next month.

 

^ Count me in, fellas!

 

Times for 5AT are much easier for most people to duplicate. As for 6MT, all the magazines use experienced drivers to lauch many times to achive the best results. Therefore, they are not easily duplicated by most of us.

 

When looking at 0 to 60 times and 1/4 mile times that extra 38hp is not much of a factor because that extra power is way up on the power band. What is important to look at is TORQUE - The magic thing that gets a car going off the line. Remember we are talking about street cars that weight 1 1/2 TONS not some 1500lb race car. It takes grunt to get these cars going. That grunt is called torque.

Many seem to be very impressed with the 05 6MT 298hp rating, but they always change the subject when the fact that Infiniti did not increase the torque in the 6MT cars comes up - Its still 260 ft lbs.

Get ready for a flame war... (hold on... OK fire suite is on) But I have stated this many times...

The 05 automatic sedan gained 20hp and 10 ft lbs of torque- don't be surprised if the auto is faster in 0 to 60 and 1/4 mile than the 6MT car.