16's vs. 17's

[dmw319]

i have a friend with some stock 16s (from a 98 camaro), and right now i have 275/40 17's on my 00 camaro. would it benefit my 1/4 time to put the stockers on for the track? how much would it help the ET? thanks.

[shenanigans]

It will help don't knoe depends on weight difference but its enough to do it,

[Fbody3400]

Originally posted by shenanigans:
It will help don't knoe depends on weight difference but its enough to do it,

Pain killer feeling good?

[shenanigans]

[img]graemlins/naughty.gif[/img] fell asleep for 4 hours last couple I took [img]smile.gif[/img]

[dmw319]

so.. yes?

[vanbibber]

Originally posted by Fbody3400:
</font><blockquote>quote:</font><hr />Originally posted by shenanigans:
It will help don't knoe depends on weight difference but its enough to do it,

Pain killer feeling good? </font>[/QUOTE]hahahaha i was thinking the same thing.

[vanbibber]

Originally posted by dmw319:
so.. yes?

it will make a slight difference

[FunkZ]

Going bigger or smaller diameter usually doesn't make much difference in weight. A 245/45R17 and wheel weighs about the same as a 245/50R16 and wheel. It's going wider or narrower that dramatically changes things. There's the old adage that 1 pound of rotational weight is like 10 pounds of static weight. So if you remove 10 pounds of wheel/tire weight in the set, you effectively removed 100 pounds from the car, which equates to roughly a .1 in the quarter. Not very precise, but a general rule of thumb.

Of course, different wheel and tire construction affect weight, by as much as several pounds. More plies make a tire stronger but heavier. Different wheel metal compositions and treatments like chrome can significantly add or reduce weight.

Also, the amount of tread on a tire can make a big difference. You can loose several pounds of tread over the lifetime of a tire. Additionally, less tread on a tire = less overall diameter, which changes your effective gear ratio. It doesn't seem like much, but loosing that 10/32 of tread can make your 3.23's effectively some 3.31's.

If you want a cheap alternative to a gear change, lower your tire profile. Going from a 235/55R16 to a 245/45 makes those 3.23's effectively like 3.43's!

[silvachris1]

My current tire/wheel setup (17x8.5s with 275/40/17s) is 56 pounds per corner. The more "stock" setup I was running (16x8s with 245/50/16s) weighed in at 42 pounds per corner. That's 14 pounds per corner, so an extra 56 pounds. I dunno about this whole rotating mass thing, if it only accounts for the rear tires cause that's what the drivetrain connects to or what? But thats an extra 28-56 pounds, or according to the RULE, an extra 0.28-0.56 seconds per run. And that's about dead on for my last trip to the track. My runs were all over the board, but way off of my best times.

[Fbody3400]

Originally posted by silvachris1:
My current tire/wheel setup (17x8.5s with 275/40/17s) is 56 pounds per corner. The more "stock" setup I was running (16x8s with 245/50/16s) weighed in at 42 pounds per corner. That's 14 pounds per corner, so an extra 56 pounds. I dunno about this whole rotating mass thing, if it only accounts for the rear tires cause that's what the drivetrain connects to or what? But thats an extra 28-56 pounds, or according to the RULE, an extra 0.28-0.56 seconds per run. And that's about dead on for my last trip to the track. My runs were all over the board, but way off of my best times.

The 'RULE' is 100 lbs. for 1 tenth. Not 10 lbs. So it would need to be 280-560 lbs. to gain .28-.56 seconds.

Of course there are a lot of other factors involved.

[silvachris1]

Originally posted by Fbody3400:
</font><blockquote>quote:</font><hr />Originally posted by silvachris1:
My current tire/wheel setup (17x8.5s with 275/40/17s) is 56 pounds per corner. The more "stock" setup I was running (16x8s with 245/50/16s) weighed in at 42 pounds per corner. That's 14 pounds per corner, so an extra 56 pounds. I dunno about this whole rotating mass thing, if it only accounts for the rear tires cause that's what the drivetrain connects to or what? But thats an extra 28-56 pounds, or according to the RULE, an extra 0.28-0.56 seconds per run. And that's about dead on for my last trip to the track. My runs were all over the board, but way off of my best times.

The 'RULE' is 100 lbs. for 1 tenth. Not 10 lbs. So it would need to be 280-560 lbs. to gain .28-.56 seconds.

Of course there are a lot of other factors involved. </font>[/QUOTE]Check out what he said about removing rotational weight.

Originally posted by FunkZ:
So if you remove 10 pounds of wheel/tire weight in the set, you effectively removed 100 pounds from the car, which equates to roughly a .1 in the quarter. Not very precise, but a general rule of thumb.

Myself...I'm planning to remove 56 pounds of wheel/tire for my next track trip. If 10 pounds of rotating weight is equal 100 pounds of static weight, then 28-56 pounds of wheel/tire weight is equal to 280-560 pounds of static weight. I just wasn't sure if the drivetrain loss due to rotational mass is due to only the drive wheels, or all 4 of them.

Or do I have this all wrong?

[Fbody3400]

^^^ Good point haha

[2001V6Power]

wow i learned something new static weight???

[Jerriko]

Rotational mass only affects the drivetrain, not the front wheels on a RWD car.

[shenanigans]

Lighter weels are better, lighter wheels in the front help weight transfer slightly.


to dmw319 question, yes ti will help you probalby a decent amount I assume you have z06 replicas and I hear most the chrome replicas are some of the heaviest wheels on our cars.