Lightweight-USPowah

I know its a big time hassle, but.. THe TT has a 66lb lead weight on the rear of the bumper which I plan on removing.. I was thinking about getting a larger spoiler to create more downforce in the rear to solve the problem of a light rear end, but figured a more sensible thing (or at least one of the things I should do), is move the battery from the front of the car to the rear.. My reasoning for this is.. if Audi thinks a 66lb weight is needed then maybe I should take the extra step and replace that 66lb weight on the back with the 40lbs from my battery... Now, what type of batteries do you guys reccomend, what sealed box, kit, or whatever? I really need help on this one.. What gauge wire should I run from the front of the car to the rear? Ill need to find a drainage plug in the rear to let the vapors from the sealed box escape.. right? I saw an ad for the optima battery which they say is is 100% sealed.. now does that mean I can actually eliminate the sealed box with a externally vented system? thanks

dingster

without any problems.

dingster

<ul><li><a href="http://www.batterymart.com/merchant2/merchant.mv?Screen=PROD&amp;Store_Code=store&amp;P roduct_Code=ODY-PC680MJ&amp;Category_Code=odyssey">http://www.batterymart.com/merchant2/merchant.mv?Screen=PROD&amp;Store_Code=store&amp;P roduct_C

Lightweight-USPowah

about 600watts for my 10" subb... DOH.. I know.. Im all about lighweight.. But damm this thing matches the interior soo well.. It'll come out for racing though.. Whats this battery rated for?

zain

To being a true dry-cell with no gasses to purge or acid to spill, they have some pretty decent cold-cranking amps capacity.

The real problem with going a long way from battery to starter is going to be the current demand at starting leading to lots of voltage drop in the wire. You need the thickest gauge wire you can manage to run. Gotta be at least as thick as the big wire on the terminals now, one size larger wouldn't hurt.

I'm not going to comment on modifying the TT weight balance, except to say: After those high speed wrecks when they first came out, I'd be sure I knew what I was doing. Audi did some things to address the problem. Was that weight back there one of them?

jussnb

You can find their contact info on their website. When you call, ask for Lloyd (the owner) and tell him that you heard about Justin's (me) battery relocation and you needed some tips.

Good luck.<ul><li><a href="http://www.tdlracing.com">TDL Racing</a></li></ul>

zain

How much would you say it really helped handling?

Lightweight-USPowah

While the rear end is a little light and does come around, I think the times it comes around is due to driver error.. Ive gotten the rear end of my TT out at 110mph, but after talking with someone that lived in my area, something like that is expected since its an off camber turn.. If you push this car too far it will come around, BUT when you get on the gas your alright.. Ive been able to control the car at auto-x events and its really not that hard.. On the street Ive gotten the rear out a few times and by applying the gas it caught.. No matter what, Im removing that weight.. It must be done.. Someone with a fwd TT did it on his car and he raced the car with no problems.. I am currently running around without a spare and without rear seats which is about 90lbs removed from the rear.. No problems at 143.. and no problems going around turns at high speeds.. I push my car really hard when I drive and haven't slid off the road.. Of the stories you hear about people sliding at 110 or whatever, my guess if that the driver was pushing the car beyond its limits, something that would happen to any car (yeah, even a Nissan maxima.. ...

zain

If the car's rear is "too light" from a handling perspective, making it lighter may not be the best plan. Moving weight from front to rear, as the battery, but NOT removing the ballast, might make more sense.

No?

Depends on why it's coming around of course. And the driver. Too little rear weight and the rear tires lack the normal force to grip. To much and the interial side load of the rear weight, while cornering, overpowers the grip and the back comes out (all assuming a neutral power turn and no throttle steer). If Audi engineers added weight to the rear, and a wing to the rear of the TT to "fix" the handling issues, then I would assume that they concluded there was inadequate normal force acting downward on the rears. Especially at higher speeds.

Quattro can definitely save you in a loose end situation, witness all the guys with 22 mm rear sways. "Kick the back out and hit the gas" as a cornering strategy.

But if the weight balance is loused up, you can get loose under *deceleration* in a corner. When you have no choice about going back to power. Like when the fool in front of you at the track screws up in the corner. I'd rather understeer than oversteer in unplanned emergency breaking.

Complicated stuff. I'll shut up.

- Z

ryoung

.
You're better off with a lightweight battery.

The normal force downward from the weight of the battery helps grip. The lateral force from the weight of the battery during cornering hurts grip, and the loss is more than you gain.

For high speed handling (if the problem is oversteer from aero lift) you're actually better off with the battery up front, but this hurts low speed handling.

The best solution is a lightweight battery in the rear, plus as much of a rear wing as your aesthetics will tolerate.