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Old 03-15-2008, 03:47 PM   #4351
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oh crap!! I forgot about sending you that email. First thing monday buddy.
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Old 03-15-2008, 04:03 PM   #4352
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Hey guys,

Maybe some here can share up what their "race-ready" weights are and what components they're using? An observation a couple of us made at the carpet regionals our club hosted last week was that there ARE cars out there "at weight" while most of us were running cars 2-4 ounces heavier. That's a heck of an advantage to give away given it's a moderately large percentage of the entire weight of the car. This is only going to get worse as we're adopting brushless esc's and motors which tend to be larger/heavier.

My BMI 19T car is equipped with:

KO VFS-1 Comp 2 esc (w/capacitor, w/o Schottky)
Spektrum 3500 micro receiver
KO 949 steering servo (using BMI aluminum servo mount)
KD 19T motor
16G wiring (3 wire layout)
Speed 12 Std wt body (re-inforced at front, probably too much paint)

(I'm not listing stuff we ALL run...PT, "race dia" tires, etc).

My car as above weighed in at 850g. The winner's car had a little weight added to make 794g.

I've done a little checking and I can lose a few grams at a time by:

Going to a 9650 or 3650 servo (both are "stronger" to boot).
Ditching the servo mount and flat mounting w/shoo goo
Either reduce reinforcement on body or go to lightweight body and continue to reinforce front.

But all these items together won't get me half way to 794g. I picked up a Tekin B1 esc for my Slider that I understand some are using for 1/12, I'm sure that would gain me a bit over the KO (which ain't especially porky...).

So I'm curious...who here is "at weight" and what are you running? Criminy...I'm going to have to go NUTS grinding on the chassis to go brushless!!
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Old 03-15-2008, 04:20 PM   #4353
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wait they run mini scale escs with a 540? how is that possible? I wonder why it weighs that much anything on the motor, like fans or an additional battery pack?
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Old 03-15-2008, 04:26 PM   #4354
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Originally Posted by Ferrarimk13 View Post
wait they run mini scale escs with a 540? how is that possible? I wonder why it weighs that much anything on the motor, like fans or an additional battery pack?
Uh...no. And "that much" was below average of the 40 or so cars weighed-in at tech for this event. A car at or below 800g isn't THAT common (in fact there was a total of 1).

Can you even weigh your car yet?
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Old 03-15-2008, 04:30 PM   #4355
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whoah, excuse me then, i didnt think anyone would get offended about their car's weight. I just thought that if yours is 850, and his is 50g lighter, what less can he have put on. Yours sounds as lightweight as possible, with the gear you have, so im just am wondering what he was running. You racers are so damn uptight sometimes.
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Old 03-15-2008, 06:18 PM   #4356
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There are a few things you can do to shedd some weight on the car. Going to all aluminum screws,shoe goo the servo,go to the super light weight electronics,use plastic front shims,super small tires,lightweight body,lose the front bumper,lightened diff rings,switch to 6 diff balls over 12(i like 12 but 6 with lightened rings will make it work and is lighter),and im sure there are a few others i just cant think of right now. This should get you around where you want to be.

I was torn between super lightweight and durability when deciding on the route to go with the car. Super lightweight is weak and does not hold up to somewhat easy hits so i decided to go with strong and a little on the heavier side and give the customer the option of going balls out and lightening the car to the extreme. I lightened mine a little but i didnt go overboard because i still need to finish the race. I messed with more cutouts in the chassis and lightening the pod but it hurt performance and really hurt the durability of the car.
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Old 03-15-2008, 06:22 PM   #4357
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Old 03-15-2008, 06:50 PM   #4358
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Originally Posted by protc3 View Post
There are a few things you can do to shedd some weight on the car. Going to all aluminum screws,shoe goo the servo,go to the super light weight electronics,use plastic front shims,super small tires,lightweight body,lose the front bumper,lightened diff rings,switch to 6 diff balls over 12(i like 12 but 6 with lightened rings will make it work and is lighter),and im sure there are a few others i just cant think of right now. This should get you around where you want to be.
I've got the aluminum screws throughout (about a half ounce there) and should have mentioned those. I've got the lightened diff rings.

The sub-800g car I refer to has 12 diff balls AND a Slapmaster thrust assy (I don't on this car), has a front bumper, etc. Not sure about the shims--any odds on a set of machined plastic shims from BMI (though I really like my 2 sets of aluminum ones)?

I'm afraid I give up most (all?) of the weight savings discarding the aluminum servo mount by adding ShooGoo and longer ball studs, regardless the minimal savings are reduced significantly.

For now I guess I install the JR3650 servo (lightest of the 3 different digital 1/12 servos I've got) and install it flat with ShooGoo, install the Tekin B-1, and do a "light" paintjob on a lightweight Speed-12 and see where I'm at. From there I start grinding on stuff. I don't do too much hard crashing--maybe Jason can pm me some suggested holes to enlarge or where to create new. Right now I'm not straying from 12 diff balls and I'll try to stay with the aluminum front spacers.

Anybody else?
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Old 03-15-2008, 08:57 PM   #4359
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Hey Scottrik,

Don't focus to much on lighting your car just concentrate on other things... setup, etc,etc. my car is on the heavy side because I use alot of steel screws I like my car to be durable. I use spray cans to paint my bodies ghetto style Lol... and thick bodys with alot of decals LOL...

My lap times are either on par or more over the fast guy's at my track.I just focus on my driving and car setup. Seriously... it works, you can be just as fast with a heavy car or faster than a light car. All this lighting stuff is in the mind and some people kind of stress out about it.

Dont get me wrong, it pretty good to have a light car but don't stress if your car is a little heaver than your competitors. remember It all in the mind

Hope this helps
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Originally Posted by Scottrik View Post
I've got the aluminum screws throughout (about a half ounce there) and should have mentioned those. I've got the lightened diff rings.

The sub-800g car I refer to has 12 diff balls AND a Slapmaster thrust assy (I don't on this car), has a front bumper, etc. Not sure about the shims--any odds on a set of machined plastic shims from BMI (though I really like my 2 sets of aluminum ones)?

I'm afraid I give up most (all?) of the weight savings discarding the aluminum servo mount by adding ShooGoo and longer ball studs, regardless the minimal savings are reduced significantly.

For now I guess I install the JR3650 servo (lightest of the 3 different digital 1/12 servos I've got) and install it flat with ShooGoo, install the Tekin B-1, and do a "light" paintjob on a lightweight Speed-12 and see where I'm at. From there I start grinding on stuff. I don't do too much hard crashing--maybe Jason can pm me some suggested holes to enlarge or where to create new. Right now I'm not straying from 12 diff balls and I'll try to stay with the aluminum front spacers.

Anybody else?
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Old 03-15-2008, 10:08 PM   #4360
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Quote:
Originally Posted by mike ivy View Post
Don't focus to much on lighting your car just concentrate on other things... setup, etc,etc. my car is on the heavy side because I use alot of steel screws I like my car to be durable. I use spray cans to paint my bodies ghetto style Lol... and thick bodys with alot of decals LOL...

My lap times are either on par or more over the fast guy's at my track.I just focus on my driving and car setup. Seriously... it works, you can be just as fast with a heavy car or faster than a light car. All this lighting stuff is in the mind and some people kind of stress out about it.

Dont get me wrong, it pretty good to have a light car but don't stress if your car is a little heaver than your competitors. remember It all in the mind
I hear ya Mike...and I agree with you up to a point. Unfortunately (well, fortunately really) my car set-up is pretty well mastered, and my driving is getting good enough now (took darn long enough...) that giving away a full 2 ounce advantage from the outset is probably not doing me any favors. 2 ounces on a TC "ain't no thang", but 2 ounces / 57 grams IS giving away quite an advantage on a car that should only weigh 794g (that's over 7%). When the game is getting a car to change direction quickly and carry speed and your personal game has reached a point, you need to minimize the advantages you're giving away.

Small "advantages" didn't matter when I couldn't drive 8 minutes cleanly. Now that I'm doing so fairly consistently I need to take things like the weight out of the equation. If you're not facing someone with this advantage it means nothing, but here in this region we are facing JUST that. AND he's a damn good wheel.

We'll figure it out.
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Old 03-15-2008, 10:11 PM   #4361
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My bone stock steel DB12R with a spectrum Micro RX, Futaba 9602, Keyence Rapida Pro (14g wires), IB 4200's, Trinity CO27 and spray can painted Protoform Speed 12 weighs 28.5oz on the Florida Sate Series Scale. Thats 808g.

Jason's is identical but with the big spectrum rx and weighs 28.7oz (813g).

Our min weight is 28oz or 798g so we are pretty darned close to min weight

Standing at our tech area we see that we regularly have two of the lightest cars in the state. Most of the cars I see are 30oz or more.
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Old 03-15-2008, 10:52 PM   #4362
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Not sure how you get your car so light. My bone stock car running a regular spektrum receiver, Futaba 9602, KO VFS ESC, 16 gauge wiring, CP money motor and LW speed 8 came in at 1.92lbs (870gms).

I know my car is fat but it runs well and I see no need to risk that in a fight to lose weight. I changed to brushless for a weekend a couple of months ago and it totally screwed up how the car drove (I now suspect my wiring was causing a tweak) so I'm now loathe to make any major changes from a car that runs well.
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Old 03-15-2008, 11:02 PM   #4363
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Wow, I just weighed my car and adrian is right. It is actually 28.5oz(806g) with pt and body all ready to race. My brushless car with the SP GT speedo came in at 30.5(862g) with body all ready to race.
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Old 03-16-2008, 12:56 AM   #4364
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Three key areas for weight...

Body - a lightweight Parma Zytek is worth about 20g over the standard shell
Motor - a Checkpoint Money is the lightest 19T motor by about 17g.
Cells - 3700 cells are about 30g (4-pack) lighter than 4200, and I have about 15g variance in the six packs of (supposedly!) identical LRP VTEC Big Mama 4200 cells. Being good at soldering also makes up to a 10g difference to the final pack weight.

Aluminium is half the weight of steel, titanium is 2/3 the weight, so ally screws wherever appropriate.

My car with 9602, LRP Sphere, LRP X11 BL, 4200 cells, L/W body, Spektrum micro receiver and ally screws in some areas is 850g. At our GP - currently in progress this weekend - the TQ car comes in at 870g. That's the joy of 12th, it almost doesn't matter at all what you put in the car, or what it weighs - if you can drive, you can drive!
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Old 03-16-2008, 01:00 AM   #4365
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Big choice this year

Race REEDY

Buy a DB12R, or a DB10R HMMMM lol

I dont really want to read back, anything new with the 12R?
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