vplukas101 - does the RA have any sound deadening under the seat and under all that plastic? i must be getting old in my age because i feel like it needs more soundproofing.

OP - i think it's already been covered, but what i'd do to keep it stock interior and have weight reduction is just work on the unsprung mass on the suspension. aluminum body coilovers, lightweight brake kit, and lightweight wheels is the best we can do. if you can find some 12 lb forged 17's, you'd benefit greatly! another thing you might want to consider for improving engine response is lightweight/underdrive pulleys. they made a huge difference in my previous car. the engine could rev so much more freely.

just looking at wheelweights.net for a bit and

RPF-1 17x7 15lbs cast // 17x8 15.6lbs // 18x8 17.8lbs
Motegi Track Lite 17x7 14.5lbs forged
RO_JA formula 5 17x7 14.5 lbs forged
Advan RG 17x7.5 15.2 lbs forged
buddy club P1 QF 17x7.5 12.9lbs forged
gramlights 57f 15lbs forged
EVO 9 BBS wheels 17x7.5 17.8lbs forged
SSR Competition 17x7.5 13lbs forged // 18x8 16.3lbs
Volk CE28N 17x7.5 13.8lbs forged // 18x8 14.7lbs
Volk TE37 17x7.5 15 lbs forged // 18x8 18.1lbs
weds sa-70 17x7.7 16.7lbs cast

anyway, i read in either Modified or SCC (it was the Technobabble column) that a 1lb weight reduction in rotating mass on the outer edge of the wheel is equivalent to removing 30lbs of interior. so technically if you bought CE28Ns and saved 6lbs per corner, it would be like removing 180lbs of interior.

 

I'm confused
Using a 1:30 ratio-
6lbs x 4corners = 24lbs total.
24lbs total x 30lb reduction equivalency (source unkn) = 720lbs.

 

fixed

 

RA and Evo x hoods are both the same aluminum. if your cars not your DD just take out everything..............

 

see, i was thinking that, but it seemed impossible so i just posted the 180lbs. good to know someone else has read the article [or something similar].

 

Should be fairly easy to test then.
Get (3) people of 240lbs, and (1) person of 180lbs.
Time the RA loaded, then time it with just the driver.
Calculate the percentage decrease in time.

Next, time the RA with stock wheels and (1) 180lb driver. Then reduce the unsprung weight/rotating mass and time with the same 180lb driver.
Calculate the percentage decrease in time.

For the first test set, I know this would be adding supplementary weight with the wheel weight, so it wouldn't be exact. It should be similar though.

If percentages for test sets (1) and (2) are close to 1:1, then 720lbs would be correct (test (1) 15% : test (2) 15%).

Hypothetically, if there is found to be a greater ratio in test set (2) than test set (1) it removal of the rotating mass would account for more interior mass removal than originally thought. Example: test (1) 15% : test (2) 30%, then the reduction in unsprung weight would count for approximately 1440lbs interior mass.

Respectively, if the ratio in test (2) was less than test (1), then removal of rotating mass would account for less interior mass removal. Example: test (1) 15% : test (2) 5% (3:1), then reduction in unsprung mass would account for approximately 240lbs of interior mass.

 

the proper testing is definitely do-able. i was just basing the numbers on his original theory though, just correcting his math, lol

 

it has no sound proofing and i only took plastic off from under the motor

 

Solid info. Bumping to top.

 

I'm not sure if this was mentioned or not( I didn't read every single post), going on a diet might help too.

 

We actually added a sticky thread in the "handling" section for this exact topic. I just forgot to link and redirect traffic from this thread over there.


Lots of good info here:
https://www.evolutionm.net/forums/09...gs-thread.html