thwang99

Hi all,

I got an RX400h, and in a quest to lighten the car, managed to remove about 100+ pounds from it!

Measured with a bathroom scale so don't know how accurate it is.

I want to replace the stock 17" rims with aftermarket 17" rims, what is the lightest rims out there?

I want to keep the rim/tire combination the same as stock.

Actually I wouldn't mind going with a 16" rim and slightly smaller tires, as long as it looked stock, as I think smaller tires improve mileage, right? That's why the prius has such small tires?

- Tony

CK6Speed

iTrader: (1)

So what did you do to remove the weight?

rxdriver

How? From the driver? Congrats!
I can't picture the car in the bathroom...

thwang99

Yes, I saved 100+ pounds by removing the driver. And you know, you don't have to weigh the car to figure the weight reduction, I just weighed myself and deducted that weight from the weight of the car when I drive it.

Though the car is much less useful when I'm not in it.

(the below breakdown in weight is from memory)

No, I just removed the spare tire (55 or so pounds?) and tools (10-15 pounds?), cargo mat (5 pounds), manuals and stuff in glovebox (5 pounds?), plastic engine covers (5 pounds?), replaced the battery with a lightweight 14 pound battery (20 to 25 pounds?).

Wonder if there's anything else I might have missed! Most of the weight reduction is in the rear of the car, which is something I'm sort of worried about but not really, cause I didn't reduce that much weight.

- Tony

dolesun

I really doubt saving 100 lbs makes much diff., but 500 lbs will.

Lil4X

"Faint heart ne'er won fair drag race!" - attributed to Don "The Snake" Prudhomme.

Lessee . . . remove a coupla doors, maybe the gas tank (especially if full), and the radiator. Throw out the back seat, torch off the roof and remove the glass . . . then you won't need the AC or heater - they're gone too.

Remove all wheels/tires and replace with 26 X 1 "clincher"-type bicycle tires (with appropriate rims), removing the need for power steering and brakes (use the handbrakes from the bicycle).

Pull the engine - the electric power system will move the vehicle with great authority once the weight of the engine and transmision are gone.

I bet it would go really really fast then!! . . . well, downhill anyway!

Lexmex

I have been doing a project with my RX300 for some time, but more related to my pursuit of 1/4 mile racing activities down here.

I have read but cannot confirm, 6 pounds = 1 hp

In some other places I have read that 100 lbs lost...then .1 seconds more in the 1/4 mile. I do not think from experience this is correct.

Anyway, I used to do something like 19.2 to 19.6 on stock about a year ago (at 7,400 foot altitude at the track) and now I just broke my own record and hit 18.207, 2.694 60 foot time, 122.03 km/h (and this is summer...so wait for winter). Some people tell me that this would hit like high 15s/ low 16s at sea level. I still do not buy that 16.8 1/4 mile stock time.

To give you an idea, a V8 Jeep Grand Cherokee will run about 18.5 on a real, real good night. Neon SRT-4s run in the 14s.

You got it pretty much correct to start, but here are my own reductions:

1) Everything such as tools, spare tire, the manual. Dump all garbage!
2) Removed that bulky airbox and the air intake resonator and made my own lightweight mod
3) Off came the exhaust resonator (this is Mexico...nobody cares about noise) and that thing weighs a ton (will put a small cone resonator when I get back to the states)
4) I have an Optima battery, but not sure what that thing weighs
5) That muffler...big...bulky...useless...switched to a direct flow and lightweight muffler
6) There is also a weight that is attached to the front of the exhaust resonator and a damper by the gas tank on the passenger side

I was thinking of some nice Racing Hart rims. These things really are lightweight and mucho $$$. Then scrubbing my 235-70-16s CTXs and lowering my RX with something like a 225-55-16 Michelin Sports. I use nitrogen in my tires.

Lightweight shocks...though I have not seen much beyond KYBs. Brake rotors would also be on the cutting the fat list.

I also heard that there is something 60 pounds of sound deadening material underneath the carpet.

dough boi

I never understood removing things such as the spare/tools for weight reduction, I mean it's not a race car you only drive on the track, its something you drive everyday, where the spare/tools comes in handy, and what's the point of removing sound deadening in a rx? It a luxury SUV, not a race car. Why buy a comfortable lexus, just to make it uncomfortable, if you wanted a light quick car, I think a lexus is the last thing that should be on your list. What exactly is your goal from removing all this weight? More speed? It makes no sense to me to try to do weight reduction to a RX, please, fill me in.

spwolf

p.s. stock wheels on RX400h are 18".

Lexmex

I actually want to be unique. At my track, my Lexus has a cult following simply because it beats stuff it should not beat.

I view my RX rather differently from a Luxury SUV. I bought it because it had good quality and liked the design.

You are correct removing the things I did, does not add up to much in terms of power. However, given the modifications I put in the place of the things I removed...that is what gave me power.

For me, I never saw much sense in buying a new RX330 or RX400h (though I respect those who did) when I could modify what I have. I am the kind of person who will keep a car like 10 to 15 years...so I want to enjoy it the way I seem fit.

My final project for my RX will be to install a turbo system...though this is going to take some work.

koolaidman

bad choice on removing the 12v battery. how bout u remove the 800lbs 384v battery and while ur at it lift the car and cut the orange wire under the car. u will lose like 100 lbs from that

mmahamm

Yeah, who needs a spare tire?!

nthach

acutually, the battery pack in the RX is a bit bigger than the Prius one, it's just a module of 200-300 D-cell NiMH batteries. Maybe custom-designing a Li-Polymer one is best...

thwang99

PPL do that for the Prius, I heard it costs like $7000 though! But supposedly you can go 4 months without refueling if you charge the batteries overnight at home.

- Tony

koolaidman

uhh...how bout just cutting the orange wire under the car ull drop some major weight