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TC weight reduction and lap times

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TC weight reduction and lap times

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Old 02-25-2019, 07:53 AM
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Default TC weight reduction and lap times

Iím curious about what speed gain you can achieve by lightening your car. This is my observation:

My USGT is about 50 grams overweight. Iíve lighten the car by 20 grams and I was able to gain about a tenth per lap. This is a fairly large track and my consistency is hovering around 98%. Driving wise I really canít tell any difference but average lap time is about a tenth faster. I will lighten the car further in the near future and see what additional gains I can get. What kind of speed gains were you able to get?

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Old 02-25-2019, 08:16 AM
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My experience so far is, that you gain no advantage if you are below 1250g.

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Old 02-25-2019, 08:46 AM
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wait for Bert's answer
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Old 02-25-2019, 09:29 AM
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Assuming the track offers decent grip, I think it's safe to say lighter is faster until you compromise CG or weight balance. The tipping point where you start going backwards will depend on car and surface grip.

...then again, I'm not a super fast guy so maybe I'm wrong.
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Old 02-25-2019, 09:44 AM
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I agree with JeffC - it depends how the car is being made lighter. A lighter body is almost always better, a lighter chassis plate is usually not. Generally if you can make the car lighter and lower the CG at the same time, and/or improve balance, polar moments etc - you are golden.
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Old 02-25-2019, 09:58 AM
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I agree with everything that's said...that it's not just about lightening the car but lightening the car strategically. I'm running on high traction black crc carpet. I'm just curious what others have experienced in terms of lap time when they've strategically lighten their car. My hypothesis is that if I can get my USGT car right at legal weight limit, I’ll be able to shave 2-3 tenth per lap. The current USGT record on my track is 11.8 sec/lap. My personal best is 12.4. We run CanAm motors and fixed FDR so everything is apples to apples.
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Old 02-25-2019, 04:23 PM
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Originally Posted by Marcos.J View Post
wait for Bert's answer
Ahahahah......
Yes, body weight loss makes the most difference(over one second per lap) as well as lowering the body... Assuming you setup(0.5* toe F&R) your car with a stiff enough swaybar that stops chassis scrubbing in the corner, losing rotational mass and drivetrain friction will net you another 0.5sec/lap, but there are other stuff independent of weight loss that can net you even more laptime drop like a complete car wax&anti-static treatment, increasing your speed control creep or radio sub trim, and CA your belt pullies(might be illegal), cranking the rotor's magnetic timing or slight demagnetizing effect(big can am secret), etc,.......

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Old 02-25-2019, 05:34 PM
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Originally Posted by bertrandsv87 View Post
Ahahahah......
Yes, body weight loss makes the most difference(over one second per lap) as well as lowering the body... Assuming you setup(0.5* toe F&R) your car with a stiff enough swaybar that stops chassis scrubbing in the corner, losing rotational mass and drivetrain friction will net you another 0.5sec/lap, but there are other stuff independent of weight loss that can net you even more laptime drop like a complete car wax&anti-static treatment, increasing your speed control creep or radio sub trim, and CA your belt pullies(might be illegal), cranking the rotor's magnetic timing or slight demagnetizing effect(big can am secret), etc,.......
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Old 02-25-2019, 06:42 PM
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What the f**k did I just read.. I'm so lost..
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Old 02-25-2019, 07:03 PM
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Originally Posted by Hopscotch View Post
What the f**k did I just read.. I'm so lost..
You read a message from a local politician.
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Old 02-26-2019, 01:24 AM
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I didn't feel like clicking the like button over & over so I'll just say I liked all the comments except Marcos.J's in post #3.
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Old 02-26-2019, 01:53 AM
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You could try something a little different to see how weight affects performance. Instead of spending tons on lighter parts, try adding cheap lead weights and see if it slows you down. I've added weight and gone faster before.
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Old 02-26-2019, 01:57 AM
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Originally Posted by gigaplex View Post
You could try something a little different to see how weight affects performance. Instead of spending tons on lighter parts, try adding cheap lead weights and see if it slows you down. I've added weight and gone faster before.
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Old 02-26-2019, 03:30 AM
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Going faster with more weight.. I'm sure it wasn't the weight being a favor in that.

All joking aside remember balance is key, I rather have a car be 50g over and perfectly balanced then be right at minimum weight and not balanced at all.
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Old 02-26-2019, 09:09 AM
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Balance is very important and I agree…but only to a degree. Ultimate goal is still lap time. A slightly unbalanced car will not penalize lap time that much...and there are ways to compensate for an unbalanced car via setup. The challenge is finding that right balance between weight reduction and L&R balance. Anyways, back on topic. What kind of lap time increase can one expect from 50g of strategic weight reduction? My guess is 2-3 tenths per lap on a large high traction track. What’s your guess or experience?
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