Notices
Series I Aftermarket Performance Modifications Discussion of power adding modifications

Reduce unsprung weight or add power/tq?

Thread Tools
 
Search this Thread
 
Rate Thread
 
Old 03-09-2008, 01:51 PM
  #1  
Registered User
Thread Starter
iTrader: (2)
 
Optical TDI's Avatar
 
Join Date: Dec 2007
Location: Cleveland
Posts: 184
Likes: 0
Received 0 Likes on 0 Posts
Reduce unsprung weight or add power/tq?

I'm considering one of these 2 options:

1. Enkei RPF1 wheels in stock size = 4 lbs. per corner weight reduction

2. Cobb AccessPort = 10 whp / 10 wtq

The price difference is not an issue, but I want to know what will better help accleration.

Thanks.
Old 03-09-2008, 01:55 PM
  #2  
Registered
iTrader: (7)
 
invasion08's Avatar
 
Join Date: Nov 2003
Location: New jersey
Posts: 2,079
Likes: 0
Received 2 Likes on 2 Posts
I think the wheels would help alittle bit more to get better accleration
Old 03-09-2008, 02:04 PM
  #3  
Registered
iTrader: (7)
 
invasion08's Avatar
 
Join Date: Nov 2003
Location: New jersey
Posts: 2,079
Likes: 0
Received 2 Likes on 2 Posts
My reason behind this power to weight ratio. Lets say the car weighs 3400 lbs and makes 200hp. Wioth the Cobb AccessPort you make 210. 3400/210=16.19.
Now with the new wheels the weight of the car is now 3384. And 3384/200=16.92. I know there isnt a big difference between the two products.
Old 03-09-2008, 03:19 PM
  #4  
Hit & Run Magnet
iTrader: (3)
 
kersh4w's Avatar
 
Join Date: May 2007
Location: DC Area
Posts: 6,690
Likes: 0
Received 3 Likes on 3 Posts
lets not forget he is talking about acceleration. the wheels are unsprung weight. just their pure physical weight reduction is not only noticed. its more than that. since the rotational mass of the wheels is reduced it takes a lot less effort to turn the wheels.

+1 for wheels.
Old 03-09-2008, 03:22 PM
  #5  
The Professor
 
staticlag's Avatar
 
Join Date: Aug 2004
Location: Omaha, NE
Posts: 3,479
Likes: 0
Received 6 Likes on 5 Posts
wheels are rotational weight, just like a lightweight flywheel or pullies.

Order of performance gain

rotational weight(wheels, pullies, flywheel, light clutch, brake rotors)>unsprung weight(brake calipers, suspension parts)>sprung weight (everything else in the car)
Old 03-09-2008, 03:27 PM
  #6  
Registered User
 
PhotoMunkey's Avatar
 
Join Date: Apr 2006
Posts: 670
Likes: 0
Received 0 Likes on 0 Posts
The wheels work great! Saving brake weight= good. Saving exhaust system weight= good. Clutch and flywheels saving weight= good. Do you sense a trend?
Old 03-09-2008, 03:27 PM
  #7  
Hit & Run Magnet
iTrader: (3)
 
kersh4w's Avatar
 
Join Date: May 2007
Location: DC Area
Posts: 6,690
Likes: 0
Received 3 Likes on 3 Posts
except reducing sprung weight is free. :D just remove it.

also, the curb weight of the rx8 is 3053lbs.
Old 03-09-2008, 03:30 PM
  #8  
I ♥ Drifting!!!
iTrader: (6)
 
imput1234's Avatar
 
Join Date: Mar 2007
Location: Lexington, KY
Posts: 3,069
Likes: 0
Received 5 Likes on 3 Posts
Get the RPF1.
The wheels will help in multiple categories:
acceleration
steering
handling
looks
...
Old 03-09-2008, 03:31 PM
  #9  
The Professor
 
staticlag's Avatar
 
Join Date: Aug 2004
Location: Omaha, NE
Posts: 3,479
Likes: 0
Received 6 Likes on 5 Posts
Originally Posted by kersh4w
except reducing sprung weight is free. :D just remove it.

also, the curb weight of the rx8 is 3053lbs.
Very true!
Old 03-09-2008, 05:24 PM
  #10  
the shit starter
 
Keef's Avatar
 
Join Date: Mar 2006
Location: Houston
Posts: 673
Likes: 0
Received 0 Likes on 0 Posts
I've been debating in my head what road to take. The light 17's, or nice looking 19's...

Keep in mind my version of nice looking 19's are some clean 5-spoke's powder coated dark gun metal. The only wheel I like for looks (in my opinion) on an 8 are some TSW Vortex. 19x9.5 all around, if it could fit would look nice...

I dunno, getting 17's would make it quicker, but looking good happens even when your parked.... You don't need to drive to prove what you payed for on 19's... And is 3 pounds the best there is? The lightest best looking wheel I've found are some Velox Pg-Rev10's but those things are not produced anymore, to bad because it weighed 12-13 pounds...

If I found a leightweight style wheel with the design I like than I'd be a buyer, just seen RPF-1's too many, everywhere...
Old 03-09-2008, 06:19 PM
  #11  
road warrior
 
LionZoo's Avatar
 
Join Date: Feb 2006
Location: Oakland and Los Angeles, CA
Posts: 1,861
Likes: 0
Received 3 Likes on 3 Posts
Originally Posted by kersh4w
also, the curb weight of the rx8 is 3053lbs.
Depends on the model. A fully loaded GT with nav comes in at 3060. Considering a base lacks the HIDs, DSC, TCS, moonroof, power and heated seats, Bose audio with 6 disc CD changer, navigation, keyless start, and satellite radio, I'm pretty sure a base will come in under 3000 pounds.
Old 03-09-2008, 06:31 PM
  #12  
Drive it like u stole it!
iTrader: (2)
 
chancejat's Avatar
 
Join Date: Nov 2007
Location: mobile, al
Posts: 1,050
Likes: 0
Received 0 Likes on 0 Posts
get the access port...6% horsepower gain throughout the hp curve and like 100 other very useful tools
the wheels imo would help very little with accel, try going to subway instead of micky d's for weight loss, hold the cheese...

Last edited by chancejat; 03-09-2008 at 07:54 PM.
Old 03-09-2008, 06:34 PM
  #13  
Registered User
iTrader: (2)
 
jones75254's Avatar
 
Join Date: Oct 2006
Location: Ohio
Posts: 1,396
Likes: 0
Received 0 Likes on 0 Posts
Get the wheels, acceleration as well as cosmetic appeal.
Old 03-09-2008, 06:40 PM
  #14  
Momentum Keeps Me Going
 
Spin9k's Avatar
 
Join Date: Sep 2002
Location: Colorado
Posts: 5,036
Likes: 0
Received 4 Likes on 4 Posts
Originally Posted by Optical TDI
I'm considering one of these 2 options:

1. Enkei RPF1 wheels in stock size = 4 lbs. per corner weight reduction

2. Cobb AccessPort = 10 whp / 10 wtq

The price difference is not an issue, but I want to know what will better help accleration.

Thanks.
Enkei 17x9 RPF1 45mm offest 15lbs - 1 inch wider perfect for 245/45/17" tires - 6 lbs per wheel - 24 lbs off rotational weight, plus same 24lbs off unsprung weight, plus same 24 lbs off total weight.

win - win - win

better acceleration, faster braking, lighter car - why do you care what people think your car looks like? For most people, even forgeting the wheels, it looks hellof a lot better than what they own anyway.
Old 03-09-2008, 07:40 PM
  #15  
Registered User
 
WoodsOfGreenRx8's Avatar
 
Join Date: Dec 2006
Location: Omaha
Posts: 1,015
Likes: 0
Received 0 Likes on 0 Posts
What about a set of wheels, running at between 8-9lbs per corner?

http://www.racelinewheels.com/p-224-magnesium.aspx

Too bad they only come in 17x7.5 .... I know that will pretty much put everyone off.

Last edited by WoodsOfGreenRx8; 03-09-2008 at 07:49 PM.
Old 03-09-2008, 07:48 PM
  #16  
Mu ha.. ha...
 
Razz1's Avatar
 
Join Date: Aug 2004
Location: Cali
Posts: 14,361
Likes: 0
Received 3 Likes on 3 Posts
A wheel that light can even get damaged running off track or over the aprons.

Definately not for the street.

Besides they are7.5" wide.

I vote .. go for the wheels over Cobb
Old 03-09-2008, 07:53 PM
  #17  
Registered User
 
WoodsOfGreenRx8's Avatar
 
Join Date: Dec 2006
Location: Omaha
Posts: 1,015
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by Razz1
A wheel that light can even get damaged running off track or over the aprons.

Definately not for the street.

Besides they are 7.5" wide.
I did a little research, and I could be wrong about it, but car manufactures, etc have been using Magnesium for quite a while & it is supposed to be pretty strong.. Again, I could be wrong.. Also, yea.. It blows they only come in 17x7.5 .. It is the only size they are offering & I edited my post..
Old 03-10-2008, 02:55 AM
  #18  
is adjusting valve lash
 
TrochoidMagic's Avatar
 
Join Date: Sep 2007
Location: hollywooood!
Posts: 1,060
Likes: 0
Received 0 Likes on 0 Posts
losing weight off your car IS equivalent to gaining hp...
actually, rather increasing ur power-to-weight ratio. plus the fact like all mentioned, better accel, braking, cornering, gas saving, and your pads lasts longer... whats to lose?
Old 03-10-2008, 12:11 PM
  #19  
Always lurking
 
JB_Rotary's Avatar
 
Join Date: Aug 2005
Location: Chicago, IL
Posts: 316
Likes: 0
Received 0 Likes on 0 Posts
Saving weight is much better than simply upping the hp. It will effect braking, accelerating and handling in general. Lotus has used this strrategy for a while. +1 for the wheels

Last edited by JB_Rotary; 03-10-2008 at 01:19 PM.
Old 03-10-2008, 12:26 PM
  #20  
Registered
iTrader: (1)
 
r0tor's Avatar
 
Join Date: May 2003
Location: PA
Posts: 3,754
Likes: 0
Received 0 Likes on 0 Posts
however, by the time your done getting a lightweight set of wheels and some good rubber, your looking at over a $2k bill... you better be gaining a shitload of performance for $2,ooo
Old 03-10-2008, 12:40 PM
  #21  
Official Post Whore
iTrader: (2)
 
pdxhak's Avatar
 
Join Date: Jan 2003
Location: Portland,OR
Posts: 10,462
Received 31 Likes on 27 Posts
Originally Posted by Keef
I've been debating in my head what road to take. The light 17's, or nice looking 19's...

Keep in mind my version of nice looking 19's are some clean 5-spoke's powder coated dark gun metal. The only wheel I like for looks (in my opinion) on an 8 are some TSW Vortex. 19x9.5 all around, if it could fit would look nice...
My 19x8.5 wheels weigh 2lbs less than OE wheels. In addition my tires also weigh 2lbs less than what came with the car so that is 4lbs less per wheel. Of course this is not the same savings you would get with RPF1 wheels but it is still a decent weight savings.
Old 03-10-2008, 12:47 PM
  #22  
Momentum Keeps Me Going
 
Spin9k's Avatar
 
Join Date: Sep 2002
Location: Colorado
Posts: 5,036
Likes: 0
Received 4 Likes on 4 Posts
Originally Posted by r0tor
however, by the time your done getting a lightweight set of wheels and some good rubber, your looking at over a $2k bill... you better be gaining a shitload of performance for $2,ooo
There's no shortcut to meaningful improvements, whether it be acceleration, braking improvement, steering response, better lateral Gs, improved ride, taughter suspension response, or improved mileage, for example using weight loss in specific components.

If you think losing pounds is troublesome and and expensive, Mazda (and other manufactures) often work on a "by the gram" weight loss improvement effort to reach their performance design goals. And here we are attempting to 'guild the lilly' so to speak, as Mazda is already done with their effort pretty much on our version of the 8!

But it all adds up - just like Karma
Old 03-10-2008, 01:11 PM
  #23  
road warrior
 
LionZoo's Avatar
 
Join Date: Feb 2006
Location: Oakland and Los Angeles, CA
Posts: 1,861
Likes: 0
Received 3 Likes on 3 Posts
Honestly if you just want improved acceleration, the Accessport might be the way to go. While wheels help in all dynamic situations and the Accessport doesn't, for acceleration purposes 10 hp might do more than a few pounds off the wheels.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
New_Mazda_Guy
NW RX-8 Forum
14
09-19-2019 11:20 AM
fourwhls
RX-8's For Sale/Wanted
7
02-20-2019 05:16 PM
hufflepuff
Series I Wheels, Tires, Brakes & Suspension
6
05-30-2016 10:45 AM
archon
RX-8 Parts For Sale/Wanted
3
10-01-2015 06:08 AM
jasonrxeight
RX-8's For Sale/Wanted
2
09-30-2015 01:53 PM



You have already rated this thread Rating: Thread Rating: 0 votes,  average.

Quick Reply: Reduce unsprung weight or add power/tq?



All times are GMT -5. The time now is 05:24 PM.