Thunderbolt

OK, enough of the idle chatter. Steve C, you seem to have quite a lot of experience with sports cars. I do not; my background is with stock cars. Instead of all of us fighting how about answering some questions for us? How do you set up your weight distribution? Do you bias your side weights to one side or the other or do you set your side weights 50/50 with driver? Do you set your cross weights a certain way? What do you think would be the best way to set weight distribution? Use adjustable Coil Overs, spring shims, or Weight jacks?
What are your opinions as to how the Z could be set for a road course? Yes we know there are gains to be made but what can a grass roots person do? This car is in its second childhood. There are very few parts out there to help in handling and performance so we are back to square one.
If my memory serves me right the M series came much later in BMW's product cycle. If time holds out Nissan may have an R series car to compete with the M, until then we should look at 3/5 series to the 350Z not compare M series to the Z.
Hope to hear your thoughts on the above racer to racer.
Thanks, Thunderbolt.

Elistan

I'm not steve, but I'll share some of my thoughts.

Taking a street car and putting it on the track as a weekend DE vehicle, there's very little you can do about weight distribution. It's only when you're getting into the fully stripped realm that dwnshift is visiting for Grand-Am Cup that you can start doing some setup - and even then you're limited. Your min spec weight can be a large factor in this, too. I've been crew for an Audi S4 team - stock, the car is in the 3600lbs range. Grand-Am allows us to run at 3100lbs, the fuel cell is in the trunk, but even then the car is pretty nose-heavy.

In the purpose-built race car area (F1, Audi R8, Riley & Scott, etc.) you can obviously have it just about any way you like but I don't know what those builders shoot for.

Maybe if you're running ovals you'll want one side heavier than the other, I dunno, but otherwise you always want left and right sides balanced.

As far as track setup, the easiest thing to change is tires. Swaybars after that. Shock and spring rates are very tricky and can take a long time to get dialed in. Pro race teams often don't have those set until the day of the race, even. National level autocrossers are always playing with different dampening settings - asphalt vs concrete, hot vs cold weather, tight vs open track, they all change how you should set up the car. And they're not allowed to change springs - imagine the additional complexity if they were.

BriGuyMax

iTrader: (4)

steveC -

earlier in this thread you stated that the 350z is heavier than ALL the corvette models, when in actuality per edmunds.com it's not.

350Z - 3188
Corvette hatch - 3214
Corvette vert - 3210
Corvette Z06 - 3116


hmm, looks like the Z06 is the only one that's lighter than a 350...and the vettes have weak fiberglass body panels...

Thunderbolt

Elistan, Thanks for the info. I have worked on both purpose built and modified factory chassis stock cars in NASCARS lower divisions.

From what you tell me most weekend trackers do not do much in the way of chassis set up. Is this because of the $$ , lack of knowing how to set their cars chassis up or no time to do the set up. On our late model car we would spend about 60 man hours a week on the car so time is hard to come by.

On circle track cars you do bias your weight to the left. we had to have 47% of the cars total weight on the right side. Front to rear and cross weight was up to us. On a road course why would you not have a little more weight on the right side since most of your turns are right handers? It would seem to me tha if the track you were on had a long sweeping right hand turn you would try to set your car up to handle that trun with as much speed as you could carry. This might slow you down too much in a left hander some where else but maybe the others would have to same issues so it would equal out.

Just some thoughts I had.

ZLuvr

Those weights are nissan/chevy's brochure #'s for their lightest models. The z06 is very close to that weight since it has few options. IOW, those are theoretical weights. The vette and the Z are much heavier(relatively) once they are optioned out.

Again, show me a 3200lb Z with all its fluids, and 1/2 a tank of gas, and i will place my deposit today.

BriGuyMax

iTrader: (4)

I never said that the 350z doesn't weight more than 3200lbs with options and fluids....

Steve c made a claim, and I disproved his claim. BOTH the vette and the 350 probably weight about 100lbs more after you factor in options, fuel, and other fluids.

He said that the 350z is HEAVIER than a vette, no matter what model. Simple as that..

steve c

I know I said that in this thread but I can’t find it. Still, a couple of points to ponder here:

Replace the base with the heavier Performance model (Weight: 3217 lbs.) the even heavier track model (Weight: 3225 lbs. ) or the even heavier touring model (Weight: 3247 lbs.) and my statement is valid. What is the breakdown of sales per model? Could I argue that the majority are heavier and be within the realms of reason?

In regards to the corvettes weight being more with options – that is true but you must consider that the Z06 for instance has very few options and according to the vette forums usually tips the scales under what Chevrolet claims.


First off, I am no expert. Like NASCAR the optimal setup changes from track to track, from car to car, from dry to wet etc. (the main difference being that you are accustomed to 2900 pounds cars with 6-700hp and not too much traction). For an example here we will use a front engine rear wheel drive car. My ideal setup to get the most in the most situations would be 50% left weight, 50/50 front/rear distribution (increasing that to an extent with a rear bias as horsepower increases), and a cross weight as close to 50/50 as possible (this is where you NASCAR guys do things that would make the car do horrible things on a road course). The cheapest approach to this is coil-overs, wedges etc.

I have no right to say whether or not the Z’s will make good track cars. Ultimately I am sure we will see a number of them running very good times. My only concern, and I have stated this from the beginning is that with increased weight comes increased tire wear, increased brake wear and slower corner entry speeds. I for one like to keep the tire and brake costs down as much as possible.

Yes, let’s hope they do come out with a worked over version similar to the M cars – but for now I guess we must settle for the track version which ironically is the heaviest of the bunch.

BriGuyMax

iTrader: (4)

Ok...even if the optioned out 350z's are a TINY bit heavier than a vette...really making a big deal about at the MOST 25 lbs is splitting hairs.

steve c

Yeah.

hurley64

The Z, for a car with a 3.5 liter V6, does seem to weigh an excessive amount. Most of the reviews that I have read indicate an "as tested" weight of 3350lbs. With 287HP its able to reach 60 in an indicated 5.4-5.6 seconds, still not to shabby.

As a comparison, lets look at a BMW Z4 3.0. This car has every luxury feature available, tilt-tele steering, heated seats, leather, convertable, but only a 3.0 liter 225HP engine, and yet its still able to zoom to 60 in 5.4 seconds!! It weighs in at an average of 3100 lbs.

This is why a lot of folks wished the Z were lighter. This is also why its ridiculous to argue that "well they made the Z heavier so it would feel more substantial". Thats so much crap! You think the Z4 feels like a yugo? Dont even get me started on a Vette comparison, the vette has a V8, is dimensionably larger and yet still weighs less than the Z, with the added bonus of 350-405 HP!!

The Z is a fatty and that fatness makes it slower than it should be. I still think its a great car but it would have been even better if lighter(wish it was cheaper too)!!

John

BriGuyMax

iTrader: (4)

The Z4 is much smaller than a Z...so that's not a good comparison. It's also much more expensive.

The vette is MUCH more expensive, and has fiberglass body panels and a cheap a$$ interior, which make it light.

Ask yourselves this question. Would you rather have the Z we have, at it's current price, or a Z that's base price is near that of a vette and weighs in 300lbs less?

hurley64

Z4 is a 2 seat car.....just like the Z. Dont think its any smaller and for 40k u dont have to take it to some crap Nissan Dealer!!

Give me a Z with 350HP and weighs 100 less and it would actually be worth 36k!! Its not like the interior is something that great, yeah its a fresh face, but the DVD Nav door belongs in a Daewoo, and the door panels are kinda plain!

John

Elistan

The only weight allocation modifications I've ever seen on a street driven car at a DE is battery relocation, but even that's pretty rare. There's really not much you can move around on a stock street car - you can do various weight reduction things like racing seats, aftermarket exhaust and such, but unless you then add weights, you're pretty much stuck with the resulting balance. My guess would be that removing 100lbs would increase your lap times better than moving 100lbs to a different part of the car. Also the mod would be fairly intrusive and weekend track junkies don't do such things to their cars mostly because it hurts the car's daily drivability so much.

I'm thinking of the three tracks I've run at - Texas Motor Speedway, Texas World Speedway, and Motorsports Ranch - and I don't see overall lap times being improved by emphasizing corners in one particular direction over another. On the oval banking of TMS you're always at WOT because the chicanes and infield slow you down, so shifting weight won't get you more speed. And the infield has an equal number of lefts and rights... TWS has a very very fast left handing coming off the oval into the infield, and another fast lefty in the backfield, but it has esses and carousels and basic rights to offset that. MSR is much the same.

I've never driven a car that was off more than a few % left to right, so I'm not sure how that would affect the car's dynamics under transitions and braking. I can only imagine that it would add some pretty bad instability when you're braking as hard as possible - the extra weight over one particular front wheel would tend to cause the other to lock up more easily, throwing the car into a nasty spin.

S38

If you have coilovers, you can corner weight the car if you have scales. My friend does it in his garage usually just trying to even it out on all corners.

One nice things about BMW's. They never have the battery up front. Either in the trunk or under the seat (like my car). The new Z4 3.0 is like 50/49 f/r balance--which is pretty amazing. This has long been a design principle of BMW even in their family cars.

Ever driven an E30 M3? That is how a car should feel. They only weigh like 2800lbs by the way.

BriGuyMax

iTrader: (4)

This is unreal...I want you to name me ONE two seater sports car out there that has at least 350hp, and weighs LESS than 3100 lbs, all while being reliable and refined...yea...that's what I though.

The Z is a GREAT bargain...you get MORE than you pay for with this car. I can't believe some of you people...you think you should get everything and not pay anything.

Elistan

Hmm... The current Porsche 911 is pretty close. 3014lbs, 320hp, plenty of refinement and reliability.

Of course, it does cost $68,600 (not including any options!)

rodH

iTrader: (2)

ya, good luck getting the 320 hp version for $68k, try 10K+ more than that.

Hurley, don't give me the "deawoo" crap, have you ever driven a M roadster convert??? talk about rattles?? I thought I was in a chevy, seriously, it was a joke, this was a car that my father brought home for us to "play with" and quality wise, I was very unimpressed, much more impressed by the S2K or M3. I was a little embarassed that BMW would put a BMW badge on that thing. I could see chevey owners test driving it and saying "I thought German cars were supposed to be refined?"

btw, for those that are impressed with the equal times in the Z4 (btw, compare 1/4 times, and the Z beats it) and the Z thinking that it is embarrasing that they are the same speed with less HP, I look at it in pure financial perspective, I am much more impressed that Nissan can build a car just as fast at much LESS $$$. the M3 is a much better more attractive package than a z4.

BriGuyMax

iTrader: (4)

still not 350hp

Peregrine

Well, there is one car with 400 HP that weighs only 3064 pounds -- a Ferrari 360 Modena. If I had $140,615 in my pocket, it would be at the top of my list...

More to the point...

Platform sharing makes the 350Z affordable. Platform sharing makes the 350Z heavier that it would be otherwise. It seems like a reasonable tradeoff for a $30K, 287 HP sports car with plenty of low-end torque. Whether this is better than a lightweight, 240HP S2000 that is much more tossable, but has much less torque, is a matter of personal taste...

ZLuvr

Hey, don't get me/us whiners wrong. The Z is the bargain of the decade, BUT, gawd i wish it weighed 3000 lbs.

To me the most exciting cars have great lb/HP ratios. So, i look at that first, and handling dynamics 2nd(i figure it is easier to improve my skills, and improve the cars handling than to try to lose 300 lbs).

Look at the sun intl' Elise with the Integra Type R engine. It has the power to weigt ratio of a viper, but on a short track with lots of turns, it would take the viper. Why, b/c, like steve C said, your corner entry speed can be much higher on the elise.