caymandive

iTrader: (2)

My first mod! I am using the same lightweight battery in the IS-F that I used on my IS350. Everything is the exact same between the cars so it was an easy swap. (2 minutes) Here is the link to my original installation with details on how it was installed. CLICK HERE

Weight specifications:

OEM battery - 42.5 lbs
OEM Hold down hardware - .5 (approx)

Odyssey battery - 16 lbs (including the black aluminum hold down box)
Mounting bracket- 7.7 oz or .48 lbs

Approximate weight savings is 26.5lbs

CrazyMPG

iTrader: (4)

heh nice!...but when you take out the original and put in this lighter one...does the settings for the car stay the same?...or would I have to go back to Lexus to redo some of the personalized settings?...thanks!

caymandive

iTrader: (2)

The only thing I had to reset was:
1. Clock
2. Windows
3. Readjust the steering position memory.
4. Memory seats

All the Nav and radio settings were not affected.

What personalized settings are you referring to?

foup

Honestly, this is not going to make any difference except that the lighter battery might cause you some unanticipated problems...
But if you were to race another isf you would have a chance, provided that he does not have an empty tank and you a full one, or that his driver is not skinny and lean...

caymandive

iTrader: (2)

Well any true drag junkie or performance addict would appreciate the mod and I just so happen to be one of those junkies. I truly enjoy racing in all it's forms and as we all know weight is thy enemy. Reduced weight results in quicker acceleration, better braking, improved handling, etc. I can tell you for every 30lbs dropped in the IS350 was worth about a 1/10th in the quarter and may be similar in the IS-F. I don't plan however on running the battery in my car all year, but just for a few months from now until December when the racing season is over.

FWIW I ran this battery in my IS350 over the summer with zero issues and I don't foresee any issues in the IS-F either. As the Guinea pig for this setup, I'll keep you all posted.

larrysb

Every gram counts.

Actually, 26.5 lbs is a pretty healthy chunk of weight to get rid off. Not sure how the battery is going to hold up with the extra load of starting a bigger V8.

Back in the day, we'd use the smallest battery that could possibly start the car and relocate it to the trunk.

LexFather

Good mod! THanks for sharing!!

foup

If I am not mistaken a full tank of 16 gal weighs 96 pounds, so yes if you love drag racing you should always run close to empty.

Seriously though, I would seek more dramatic solutions such as a carbon fiber hood , rear plastic windows , no rear seat, and no nav/ML (speakers are heavy), obviously no spare, etc.

I think your light battery is fine if you use your car everyday but may not last as long if you keep car in your garage for a week or two. Did you try that?

One HoT

iTrader: (5)

Looks great and nice weight savings!

But dry cell batteries tend to be a pain to jump especially when it consistently dies in the winter time...A traditional battery holds charge much longer than a small dry cell...I had to learn this the hard way...!

caymandive

iTrader: (2)

I should have emphasized in my first post, but this battery will only be used until December for the few months I'll hit the drag strip. I haven't had the chance to see how long the battery holds charge while not driven, but I know a few people who have been running it in their cars for years without an issue. Maybe when I take vacation in January I'll put the battery back in the car and see how it holds while I'm away.

Not that I don't believe I couldn't use this battery all year, but as you've all mentioned I too would be more comfortable for the rest of the year having the OEM battery in place.

I'll let you all know how the car does for the next few months.

ChuH

To save even more weight you can try this 4lbs racing battery.

http://www.voltphreaks.com/home.html

But at $775 to $1210 the price may not be economical.

ToothDoc

So, 26.5 pounds, 50 pounds for spare and jack... Lose some of the windshield wiper fluid (like 8 pounds) and you're almost 2/10ths quicker than stock! I still think you should consider cheap light 18" rims and put your old almost bald tires on them. That'll EASILY take more than a couple of 10ths also. You'll easily be in low 12s and almost 12.0 (IMO).

caymandive

iTrader: (2)

Toothdoc, as I mentioned in my PM.. I believe the lbs/1/4mile results will be different for the IS-F. With the extra power of the V8, it may be more along the lines of 35lbs or so for every 1/10th. Guess as time goes on I'll have a better answer. I just know that in the IS350 every 30lbs was about a 1/10th at the drag strip.

As for using the drag tires from the IS350 they won't work on the IS-F. I tried them out and with the smaller tire diameter the car was requiring an extra shift negating any acceleration advantage earlier in the run. I do agree that some nice lightweight wheels would be the best bang for the buck on the IS-F's performance as you have already shown. You have an awesome time for your weather DA and i'm sure it's a direct result of your lightweight wheels.

vboy418

Nice mod, I love the engine shot!

4TehNguyen

iTrader: (1)

id use this on a track/strip id never use it for daily driving. The capacity of that battery is going to be much less than a standard size, and im not gonna risk being stranded due to a low battery capacity