Does anybody know the weight difference between the Sport Package and the Grand Touring Package? Motorcyclists on the track estimate about 1HP per 7 lbs.

 

depending on your options, it could be a few hundred pounds (ie: no-option base HiPower vs. All-Option Auto LoPower)... and that horsepower thing... *sigh* gross oversimplification. but yes, lighter is faster.

 

The extra doo-dads from Sport to GT and my weight increase estimates are:

Mirror doo-dads............~+0.5 lbs
Leather Seat Covers:......~+2.0 lbs
Power Driver's Seat:........~+4.0 lbs
Sunroof:.......................~+42.0 lbs
Bose Audio System:........~+3.5 lbs

Total Weight Gain:......~52.5 lbs

This is about 1.7% increase in weight which equates to ~4 hp. Of course, the biggest detriment to this increased weight is the sunroof way up top making the Cg significantly higher and therefore hurting handling. I posted on Edmunds a calculation I did on the RX-8 regarding the effect of the sunroof on Cg. I can't remember exactly but it was something like a 3.2% increase.

I want leather but am not willing to get a sunroof to get it. I don't care for DSC, Xenons or fog lights either. There goes another 9 lbs. Looks like a base model for me.

 

42 lbs for a sunroof? Sorry, I don't buy that. Don't forget, it you don't get a sunroof, you don't just have a hole in the roof! Seriously, how did you arrive at that number?

 

Don't forget I estimated the weights. I got the sunroof weight estimate from some other forum where some guy actually weighed his sunroof with motor, rails, switch and that little cover doohickey. He reported 50 lbs. I then calculated the weight of the steel and headliner in the "hole" and subtracted this from the 50 lbs.

I too have a feeling that 42 lbs is overstated but I am just passing along the best information I have. However, I would be surprised if the weight increase is less than 30 lbs.

 

I agree with babylou regarding the sunroof, but I think your estimate for other items are a little bit conservative (i.e 2 lbs for the leather seats vs cloth). The added items in the GT, according to your calculations, would reflect a "loss" of about 7 HP due to weight. Good thing I ordered the SP.

 

I thought a power drivers seat would wiegh considerably more after you added in motor's, all associated mechanicals, wiring, and switches.

 

Desmo,

Your motorcycle analogy isn't correct. When people say pounds = horspower, they are really saying reduced pounds = better HP/weight ratio = equivalent horsepower gain.

For 3200 lb car (including driver,

250HP/3200lb = .07HP/lb

Taking the inverse:

1 HP for every 12.8 lb. So about 4 HP are lost due to the extra weight as Babylon described earlier.

-Mr. Wigggles

 

i can see all your points but i, for one, am not gonna sacrifice luxury for some neglible speed increase...seriously, i'd much rather have the leather, navigation, 9 speaker system, power seats, and sunroof over a car with an insignificant speed increase...if you're adding a hundred lbs. or more like an extra passenger, then i'd say that's a big difference...but 50lbs. or less isn't gonna get the base or Sport a car length over the GT

so then, does it really come down to the few extra horsepower or does it come down to the fact that you just didn't want to pay for the GT? it's like saying, "Naw, don't give me top-of-the-line, i don't want it. Also, don't sit in my car, take your own ride. Also, I won't be doing any grocery shopping cuz groceries add weight. Also, I'm going on a diet"

sorry for the rant but it's just not that big a deal...and i'm not trying to pick on you, desmo996.

EDIT: this is of course my opinion as i will be using my car as a daily driver...i can see your hesitation on getting the GT if you were, in fact, gonna gut the RX and race it, where every little horsepower counts and the extra money going towards options would just be a waste...

 

A few hundred pounds? I don't think so!

 

I understand what everyone is saying. I personally don't like weight on any of my vehicles. 30 lbs on the track on a motorcycle makes a lot difference and there is also to be said about inertia. Removing 30 pounds from a motorcycle feels like a 4.5 HP increase in power and it reflects on the lap times. I think a 50 lb on the RX8 between the SP and GT is a very conservative number. The real number is probably two fold. Time will tell. I drive my cars aggressively and every little bit counts. I don't talk on the phone when I'm driving, play with the radio or fiddle with the seat to get my b*tt warm. This car is designed to be driven hard and that's exactly what I intend to do. Remember, slower vehicles keep right. Peace.

 

maybe not in this instance, but i've seen it on older RX-7 spec sheets.

 

It is funny how you consider 100 lbs "a big difference" while 50 lbs is "neglible". Not a bunch of room there for a "medium".

It is typical that you equate weight reduction to how much better the car will accelerate. Weight also affects handling, braking, fuel efficiency, emmissions, ride and crash safety. To preempt anyone don't say that heavy is safer. Yes, added weight, in the form of strength, in the structure improves safety. Weight in tacked on items, engines or power seats, reduce safety because they increase the energy load that the structure must absorb. Added unsprung weight actually hurts handling and makes for a rougher ride.

It seems to me that Mazda, of all companies, are commited to making cars light. It is no coincidence that Mazda cars (Miata, Protege, FD RX-7, RX-8) always seem to be at the top of the list in fun to drive ratings by the magazines. Look at the RX-8, it is 10% lighter than a similar sized BMW 3.

Basically I am sick of people cracking on others that want to "add lightness" and their response is it won't help performance much and they would prefer to have their luxury items. Well, if you prefer luxury items that is fine. There are tons of 4000 lb cars with loaded to the gills with "luxury" doo dads but are no fun to drive. Like a Mitsubishi 3000GT. Buy one of those. Oh wait you already have one. So why do you want an RX-8?

 

The Rx-8 for is all about Style and grace for me. I'm not going to be racing my car down at the track. If that's what I really wanted to do then, I probably wouldn't buy an Rx-8. I'd be better off with an EVO or STI. But those cars, just aren't my style. I want a car that's fast, great looking, and something I can drive with my friends and family in it. That's the RX-8. So having the GT package makes sense to me, why? Who cares about the weight, if I wanted to save weight while racing, well it wouldn't hurt me to loose about 50 lbs. myself. Hmm, I better take out all those speakers and amp, and maybe the passenger seat, oh yeah let's take off the A/C compressor because that adds a ton of weight, because that will make me a little bit faster...

If you obsessed with speed, I don't think the RX-8 is for you.

you'll never regret having the extra's down the road. It's only when you didn't get them that you might...

 

If you raced naked and fasted for a day you could shave off about 15 lbs, which would take care of everything except the moonroof :D

 

The old "go on a diet to save weight" deal is as trite as can be. Some people aren't fatties. Some people are fat heads.

Why, oh why, if someone wants to find methods to reduce vehicle weight that others who are not so inclined pipe in and tell them not to? If one is not interested in this topic then don't freaking participate! I don't give a hoot about styling stuff like body kits/wings, metal interior trim, etc. I don't go into those threads and tell these people that they shouldn't get a damn wing because I don't like it. It's their car. Sheesh!!

Now the topic was how much weight gain the GT package has over the sport package. Some have doubted my estimates. I reitirate all of my weights are estimates. However, I do have quite a large database for component weights and used this to create my RX-8 estimates. Therefore, I bet my estimates, in total, has an accuracy of +/- 15%.

 

I think this post brings up a very valid point. A huge advantage of a NA Rotary engine such as the renesis (or a high output small displacement NA piston engine) is the weight savings it permits. From a performance point of view, light weight is ESSENTIAL for this type of design to compete against cars with lots of "torque".

I am sick of the posts saying the RX8 has no "torque". The bottom line is a WELL-EXECUTED "low-torque", high-ouput motor can compete quite well against these "high torque" machines. In additon, almost every car with "low-torque" and high HP rates quite well in the "fun factor".

However, the "torque" guys wrongly point to the RX8's low-torque, when they should be talking about the RX8's weight and somewhat compromised suspension. For months people were saying 2900 lbs or below, but now we are talking close to 3,100 lbs. (if you include the spare) for the "popular option" model, whatever that may be. That's heavier than the AWD, turbo-charged WRX. It seems if Mazda used the weight savings and other advantages of the Renesis to offset the substantial weight gains from the suicide doors (and related bracing) and various doo-das inside.

However, a lot of people like most of what the RX8 is all about and want to minimize these compromises as much as possible. Therefore, getting the lightest model is pertinent in their purchasing decison. Personally, not knowing the weights of the various models, was a major reason I did not pre-order.

 

Revhappy has a very valid point. These are the number I have come across so far. Unfortunately they don't specify the model, but they do make a point regarding weight. I'm just curious about the weight difference between the GT and SP.

From Car and Driver Magazine:
"Credit Mazda's clever packaging, which incorporates space for four adults into a body no longer than a Porsche 911. Even more important, the RX-8 weighs a mere 2940 pounds—that's 560 pounds less than the G35"

From Road and Track Magazine:
"Mazda has taken such an unusual approach with the RX-8 that it's difficult to find a direct competitor, but the Infiniti G35 Sport Coupe comes close. The Infiniti's rear seats offer more leg room but considerably less head room. Its chassis delivers more grip with flatter cornering, but the Mazda has the edge in its lighter, more agile handling feel."
Posted RX8 Curb weight=3000
Posted g35 Curb weight=3435

From Motor Trend Magazine
"At 2933 pounds, this car weighs about the same as the last RX-7"

 

Well, I'll tell you what. I preordered a GT model, because I absolutely HAD to have leather, and being a daily driver and weekender for a 28-yr old father of 2 boys (they are as excited as I am), I wanted to lean more toward the luxury/comfort side.

Here is what I'm gonna do - as soon as I get my car (first allocation) I will weigh it, and will post my curb weight and GVW.

 

I found the actual numbers for the EVO with and w/o sunroof from USA today:

"Weight is listed as 3,263 pounds (3,298 with sunroof)."

35 Lbs difference

 

various reasons...

1. my 3000GT is a '96...i bought it 3 years ago and i make about 3 times more money now than i did back then...i feel it's time for me to get a new car

2. i want an RX-8 because it has 4 doors and 4 seats...my 2 other choices were the 350Z and the G35c - the 350Z has no rear seats and the G35c has no 4 doors...the 4 door G35 looks hellacious compared with the coupe...i'm into sports cars but it was cramped in teh backseat of my 3000GT and getting in and out was a workout

3. the RX-8 is considered a "luxury sports car"...it's neither a luxury coupe nor a real sports car...in fact, it's in a class of its own, the rotary motor strengthening that position...i like rare things, which is why i bought a Blue 3000GT

you want any more reasons? if you prefer a light car then why not get a Honda Civic and gut it? drop a turbo in there and you got yourself a pocket rocket...me, i want my top-of-the-line RX-8 luxury 4 door, 4 seat sports car...

and i do firmly understand that reducing weight adds all around performance to the car...i am pretty positive that the Mazda engineers took into account all the various weight differences and optimized the car for the top of the line Grand Touring model as well as the other stripped down versions...what i'm sick of is how ppl try to compensate their purchase of a lesser model by exaggerating negligible "performance" boosts due to the weight of said luxury items

 

don't forget the 18in wheels...they are around 20lbs! that is 80lbs total. i think the 16in base wheels are 16lbs.

on my 93, i had 17in Enkei wheels...not a big jump in size from stock, but the added weight (jump from 16lbs to 19 lbs) was significantly noticable. now, back with the stock wheels, but better rubber, the 7 is back to being nimble and agile around the curves again.

with that said, i would think the engineers and designers have taken this to account as well as the rest of the items you have all said. they did not want a raw, obtrusive car with the 8. so it might appear "soft" to the hardcore drivers. oh well. i know all of you know this, so this might be a moot point.

you can always strip the car and get some Volk wheels, if you really want a "light" car.

santino

 

ooops. i did not mean to be repeating Brx8's statements.

i guess i was in the middle of replying to the post, when Brx8 posted his comments. obviously we are on the same page concerning the 8.

santino

 

The weight difference between the 16" wheels and 18" wheel packages is going to be negligible.

The tires are going to be more weight than the wheel itself and the 16" wheels will probably have heavier tires due to the taller sidewall. (getting tire weights from manufacturers isn't easy. But what I'm stating here is generally the case)

-Mr. Wigggles

 

can u get the gt package and jus get NO sun roof? because honestly i have one in my accord now and i'v used it once and thats because my GF opened it...