Weight Reduction for Road Racing

[Jiveslug]

Hey all. I am doing some research into my next road racer project and was wondering how much weight can be pulled off of a MKIII Supra NA. Since these are luxury sports cars, I am thinking that a pretty high amount of weight can be shed. Here is what I can do in the race classes I have been looking at:

Gut interior except for dashboard (incl. stereo, paneling, seats, headliner, etc)
Gut doors
Remove AC (but not heater core or ducting)
Remove spare tire, trunk carpet, sound deadening, etc.
Remove all undercoating and tar and junk
Get lightweight aftermarket wheels
Get lightweight radiator and electric fans
Remove all unnecessary electrical gear (power windows, door locks, etc)
Remove TEMS suspension and replace with racing coilovers and adj. dampers (Konis, KYB AGX, or the like)


Things I cannot do:
Replace body panels with lightweight ones
Replace glass
Remove heater core
Relocate battery/get light racing battery
Alter the frame/subframes
Remove the alternator
Lighten any engine parts except to balance/blueprint

Basically, if you are familiar with the SCCA’s Improved Touring rules, you get what I am doing here. Turbos are not allowed, so I cannot make up the power/weight ratio that way. What do you guys think? I am just interested in removing weight at this point, I will worry about adding weight back on with the roll cage and such later. Thanks!

Ryan

 

[CTsupra]

Welcome to supramania! Search around, there's tons of info on weight reduction, but not specifically for SCCA rules.

The most you could remove is about 350lbs with out removing the bumper supports and door bars. You also said you can't replace the glass, so make that about 230lbs
IMO, it isn't worth it.

 

[figgie]

sell supra

buy Miata or any other light car

Short of gutting the car,
acid dipping the entire body like ford did in the days. No way to lose a significant amount of weight.

 

[Yellow 13]

Be better off going on a diet.

 

[swaq]

How about lightweight flywheel and/or driveshaft? Or is that considered lightening engine parts? That would be a good way to shed a few pounds, but more importantly rotational mass.

 

[IJ.]

Get some exercise and lose some weight
(cheaper than trying to make a FatMk3 light and in the long run much better for your health!)

 

[Big Wang Bandit]

http://trdsupra.com/library/A70WeightIndex.pdf

Its a PDF so itll take a while to load.

 

[Jiveslug]

Thanks Hells. According to the spreadsheet you linked, I can pull approx 525-575lbs. off of the thing. Thats a pretty significant amount of weight. Considering that the MKIII Supra has to weigh 3380lbs as raced in IT, making weight would be pretty easy...

 

[prsrcokr]

Jive, Scca is strict on classing though, make sure they'll allow those removals. Replacement seats removed about 50 lbs. (net loss) and I was able to run 235/255 on 17x9/17x10 while losing 20 lbs. over the stock wheels/tires.

Yuo sure about the battery? I run an 11lb. Odyssey one which is allowed in many SCCA solo classes, not sure about IT though.

 

[Mr. Sinister]

[SOGI] Put helium in the tires. [\SOGI]

 

[AGlobalThreat]

Yuo sure about the battery? I run an 11lb. Odyssey one which is allowed in many SCCA solo classes, not sure about IT though.

Werd I was surprised to see lightweight battery on the can't list.

Lighten any engine parts except to balance/blueprint - Does that include flywheel/driveshaft?

Can't remove the heater core? Is that in the rules?

Replace body panels with lightweight ones - Can't even replace the stock hood?

Yes there is quite a bit of stuff you can remove in our cars but with what you listed you are very limited, and even though I'm a lightweight junkie I'm with CTsupra saying: it isn't worth it. Pick a different car.

 

[Wills7MGTE]

Since the SCCA won't allow turbo's I wouldnt run a supra, the supra is a Turbo Car it was designed for turbos not some pussy ass NA 6 in it. 3500+ lbs will not do well with a 3.0L inline NA 6

 

[Big Wang Bandit]

The SCCA allows turbo cars. Just this class doesn't........

 

[Wills7MGTE]

Can you do an engine swap like a 1UZFE or an LS1 or something to at least be competitive. An NA Supra is a joke when it comes to racing.

 

[Big Wang Bandit]

That would put him in a higher class.

When I tracked my car I was going against supercharged Z06's and caged CRX's since I had an engine swap.

 

[BlackMKIII]

The dead live! Talk about an old thread!

Kyle: Seriously? That's BS.

 

[IJ.]

The dead live! Talk about an old thread!

Kyle: Seriously? That's BS.

 

[Big Wang Bandit]

The dead live! Talk about an old thread!

Kyle: Seriously? That's BS.

No, really. Its the street preped class. It wasn't competitive for most of us in that class. There were the big bruisers and then my buddy Eddy with his 88 M3 Me and some swapped Hondas and the such. Its just regulation

 

[foreverpsycotic]

what suspention mods can you run? if its unlimited, coilovers. oh, get a 4.3 LSD over an open and hack off the passenger side of the dash. you only need one seat (unless you are novice) for auto-x, if you are on a budget run with the passenger seat on the drivers side.

 

[fiyota]

what suspention mods can you run? if its unlimited, coilovers. oh, get a 4.3 LSD over an open and hack off the passenger side of the dash. you only need one seat (unless you are novice) for auto-x, if you are on a budget run with the passenger seat on the drivers side.

Hey guys... you do know that this thread is from 2006 right?