Does the FR-S handle any differently with varying fuel loads?
 

I'm just curious, I'm only on my second car but one thing I've tended to notice was that a full fuel load can cause some cars to perform sluggishly. I've never owned sports cars but I'm sure they wouldn't have an issue..however I wonder how the FR-S handles given it's light weight with a full tank.

Do most of you keep the tank full for the most part?

I don't notice it as a dd at all. Sure on the track it could make a big difference but they did a really nice job of spreading the weight out at time of design.

lol

Well, now, ..... the weight difference for the FR-S between a full tank and an almost empty tank is about 70 some pounds.

mrs humfrz weighs 150 pounds (+) ...... ;)

I don't notice a performance difference between a full tank and a almost empty tank.

But I sure do notice a performance difference between when mrs humfrz is a passenger or not:

* I can't dump the clutch - cause it will hurt the car!

* I can't rev it up high - cause the engine will blow up!

* I can't take corners real fast - cause it will wear out the tires!

* I can't pass other cars - cause we will crash and die!

So, I just keep the tank pretty much full ....... and .......:cry:


humfrz

I only notice a difference with passengers...

why so funny? People are constantly going crazy on the forums about saving a 10-20 lbs.

1 gallon of gas = 6lbs.

11 gallons of gas = 66lbs


That's a 60 lb difference.

10/10 post, this is awesome

60-70 lbs. is not insignificant if you're serious, fighting for tenths of a second on a lap or a couple hundreds down a drag strip. Racing teams spend millions optimizing every piece to the minimum it needs to be.

They say it costs $10,000 to put a pound of payload into orbit around our planet.

Will it help you beat a Mustang to the next stoplight? Probably not. Will you feel it in the butt dyno as you floor it through the onramp on your way to work? Probably not. Will the car feel different at the end of a track day vs. the beginning? Absolutely, but that's not entirely due to the fuel burning off as track temperatures change, your tires wear and you either find a better line around the track or your reflexes start lagging.

tl;dr: don't worry about it unless you're racing competitively.

No.

Unless you're a race car driver, it's going to be psychological.

I'll say this though. If there is something inside my cabin or trunk that is rolling around, that will f***ing mind-rape me. I loose a good 50hp if there is some piece of sh*t rolling around on the floor. Suspension goes all wonky too and I can't go around a corner to save my life until I get out of the f***ing car and fix it.

Only married men truly understand the depths of each other's pain, lol

comin' back from Seaside we had a chance to pass so while i was cookin' it a little, my wife smiles and says "it turns so easily, like you're not even trying."

"i know, right?"

look down <doh!> 97. oops. sorry, officer.

The fuel tank is below the lateral CG. This is a relatively light fuel load. Any decrease will improve acceleration and braking. 70 lb is 3% of the total weight of the car. You will notice it if the change is instantaneous like giving a child a ride. In planes, particularly taking off on a hot day at a high altitude airport like Denver, fuel load may be the difference between going and not going. The fuel load can be as high as 50% of the weight of the aircraft. Burning 1000lb on a 17,000lb plane is the difference between going to 43,000ft and 45,000 ft.
I have had a trip out of Lake Tahoe, where if the temp went from 30°C to 31°C determined whether we could come nonstop back to Florida or have to stop in Reno.
It was takeoff performance based on having an engine failure and climbing out on one engine.
The bottom line is the hotter it is and the higher you drive the more that 70lb is going to affect your performance.

John

Like spare change in cup holder.

Nah, my wife smiles when the tires are squealing, and she's told me it sounds so much better up in the higher rpm range during spirited mountain drives. I don't think she's a unicorn, but it's possible...I have taken her to car shows on our anniversary, and an anniversary trip to the Tail of the Dragon.