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do you guys think it's thesame to go from the 12's to 11's as it is to go from the 11's to the 10's?
 

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Is there a thread starting record on this forum?

JK John, lol.

I am just going to throw it out there........if it cost you $X to go from 12 to 11's, it is going to be $2.5X to go from 11 to 10's. Just a guess, I have no experience with it, YET.
 

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I'd say it takes a lot more to go from 11s to 10s than it does 12s to 11s.

Making a car this size move down 1/4 mile in 10 seconds takes A LOT of power, and the ability to get it to the ground. I'm with Goehner and say it's 2.5x the $$ easily.
 

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Discussion Starter #5
we guys that go by a blower and go out and run 11's
thats pretty easy and anyone can do it with 10 grand or so, but then when you want another second things get alittle more involved than just slaping a power adder ontop the stock motor.
 

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we guys that go by a blower and go out and run 11's
thats pretty easy and anyone can do it with 10 grand or so, but then when you want another second things get alittle more involved than just slaping a power adder ontop the stock motor.
Yep, that's why you gotta have a goal for the car up front. However, it is cool to slap on a blower and run 11s.

I'm hoping a few tweaks to the 6 speed cars are found so we can join in some of the fun. I've got a couple upgrades in route as I type to help next year (DRs and 1400HP axles), but the avg 6 speed guy with a blower will have a difficult time hitting 11s I think. Mine still might not do it with the suspension I have installed and I ain't changing it, so I hope it does. Sam said he picked up .4 by adjusting his suspension but some of that might have been him getting used to the launch as well.
 

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That's a cool graph and makes it obvious. Horsepower power is a function of weight/ET so it makes since that it's exponential. Good find BT.
 

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The short and simple, it will be much harder to go from 11.9 to 10.9 than from 12.9 to 11.9. First, look at the percentage changes. From 12.9 to 11.9, you are trying to dump 7.75% of your total time. From 11.9 to 10.9, you are dropping 8.4%. So already you have more to compensate for in order to get that next second.

But it's worse than that. Ok, so you want to go 1/4 mile. That's 402 meters. Assuming a constant acceleration, displacement = average velocity * time. The displacement is constant, 402 meters. To drop from 12.9s to 11.9s you need a 7.75% increase in your average velocity. (402m / 12.9s) = 31.16m/s starting average to (402m / 11.9s) = 33.78m/s new average. Average velocity = 1/2 (starting velocity + ending velocity) for a constant acceleration. Starting velocity is 0, so just 1/2 of the ending velocity. So at 12.9s the ending velocity is 62.32m/s, and at 11.9s it's 67.56m/s. The ending velocity = starting velocity + acceleration x time. Again, starting velocity is 0, so just acceleration x time. For the first run that's 62.32m/s = acceleration x 12.9s. So, acceleration equals 62.32m/s / 12.9s or 4.83m/s^2. The second run is 67.56m/s = acceleration x 11.9s or acceleration equals 5.68m/s^2. All in all, your acceleration must be 17.6% higher in order to achieve that 7.75% time reduction. For the 10.9s run, you'd have an ending speed of 73.76m/s, or an acceleration of 6.77m/s^2. That's not only a larger increase in acceleration outright, but a larger percentage needed (19.2% increase needed).

But it's worse than that... For the 10.9s run for example, using the classic equations you'd be trapping at 73.76m/s which is 165mph. This is obviously very high. This is because I'm not adding in air resistance. Air resistance is also quadratic. For example, going from 170mph to 180mph you are getting an increase in resistance equal to driving 59mph! sqrt(180^2-170^2). Same thing in the above examples. So your straight acceleration must increase exponentially, and so must your ability to overcome air resistance. All in all, to cut your time in half you'll need about an 8x increase in power (making it approximately cubic). To go from 12.9 to 11.9 you need a power increase of about 27%. To go from 12.9 to 10.9 you need a power increase of about 66%.

**EDIT - BTW, that's all assuming that your newly added power adds no weight. ;)
 

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Discussion Starter #11
The short and simple, it will be much harder to go from 11.9 to 10.9 than from 12.9 to 11.9. First, look at the percentage changes. From 12.9 to 11.9, you are trying to dump 7.75% of your total time. From 11.9 to 10.9, you are dropping 8.4%. So already you have more to compensate for in order to get that next second.

But it's worse than that. Ok, so you want to go 1/4 mile. That's 402 meters. Assuming a constant acceleration, displacement = average velocity * time. The displacement is constant, 402 meters. To drop from 12.9s to 11.9s you need a 7.75% increase in your average velocity. (402m / 12.9s) = 31.16m/s starting average to (402m / 11.9s) = 33.78m/s new average. Average velocity = 1/2 (starting velocity + ending velocity) for a constant acceleration. Starting velocity is 0, so just 1/2 of the ending velocity. So at 12.9s the ending velocity is 62.32m/s, and at 11.9s it's 67.56m/s. The ending velocity = starting velocity + acceleration x time. Again, starting velocity is 0, so just acceleration x time. For the first run that's 62.32m/s = acceleration x 12.9s. So, acceleration equals 62.32m/s / 12.9s or 4.83m/s^2. The second run is 67.56m/s = acceleration x 11.9s or acceleration equals 5.68m/s^2. All in all, your acceleration must be 17.6% higher in order to achieve that 7.75% time reduction. For the 10.9s run, you'd have an ending speed of 73.76m/s, or an acceleration of 6.77m/s^2. That's not only a larger increase in acceleration outright, but a larger percentage needed (19.2% increase needed).

But it's worse than that... For the 10.9s run for example, using the classic equations you'd be trapping at 73.76m/s which is 165mph. This is obviously very high. This is because I'm not adding in air resistance. Air resistance is also quadratic. For example, going from 170mph to 180mph you are getting an increase in resistance equal to driving 59mph! sqrt(180^2-170^2). Same thing in the above examples. So your straight acceleration must increase exponentially, and so must your ability to overcome air resistance. All in all, to cut your time in half you'll need about an 8x increase in power (making it approximately cubic). To go from 12.9 to 11.9 you need a power increase of about 27%. To go from 12.9 to 10.9 you need a power increase of about 66%.

**EDIT - BTW, that's all assuming that your newly added power adds no weight. ;)
dam 66% is huge and it's gonna cost alot more than 10 grand.
Are you a math teacher on a NASA Physicist
 

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dam 66% is huge and it's gonna cost alot more than 10 grand.
Are you a math teacher on a NASA Physicist
Yeah, a good supercharger is just a start. Plus you'll need shoes that can grip the extra power.

And neither, I just program. :bigthumb: Whenever my roommate gets back from x-mas vacation he could go into a LOT more detail. He'll work for NASA when he finishes his aerospace phd this year. I can still program better though. :)
 

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I think he spent 8 years at UT and spent over $110K and has been dying for years to put all that higher education to use!!! I glad we are able to have brilliant guys figuring out how to make us go faster rather than building nukes or something! :)
 

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:icon_wink:
Yeah, a good supercharger is just a start. Plus you'll need shoes that can grip the extra power.

And neither, I just program. :bigthumb: Whenever my roommate gets back from x-mas vacation he could go into a LOT more detail. He'll work for NASA when he finishes his aerospace phd this year. I can still program better though. :)
OK so I was wrong, but he's spent years and he hasn't paid for it yet, and his roommate is (going to be) the government mad scientist.

I was pretty close though!!!!:icon_wink:
 

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Discussion Starter #16
Yeah, a good supercharger is just a start. Plus you'll need shoes that can grip the extra power.

And neither, I just program. :bigthumb: Whenever my roommate gets back from x-mas vacation he could go into a LOT more detail. He'll work for NASA when he finishes his aerospace phd this year. I can still program better though. :)
very impressive, i guess i hung out in the woods drinking to long, bye 5:30pm i can't even add 2 + 3 without the calculator
 

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I think he spent 8 years at UT and spent over $110K and has been dying for years to put all that higher education to use!!!
Ha, all of that is true but not in the way you'd expect. I've spent 8+ years at UT because I suck at going to school and doing homework. I'm dying to put it to use because I hate my job and want a new one that doesn't suck! :guiness:

Also, as far as helping you go faster, I have no clue. I'm just saying each second gets so much harder. There's a reason a top-fuel dragster needs 7,500+ HP to get 4.5s.
 

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do you guys think it's thesame to go from the 12's to 11's as it is to go from the 11's to the 10's?
oh hell no! it takes for each tenth after you reach the 12s it takes more hp or wieght reduction per tenth than before. i sometimes dont understand how people can even do the math.. Im running a low low 12, stock i ran a low low 13.. Im running 110 hp more than stock. it would take me 200 more to get my low low 11. 100 more hp might net me a solid 11 second pass 11.5 or so.
then added hp you have to have added traction ect. so you can actually hurt yourself with the hp..
the old story whats the difference in a 13 second stock supra and one you have 30k in.. nothing but the 30k you just spent.. I wish i had the cash flow or drive to build the 10 second car..
 

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well I jog a 1/4 in about 2 minutes, paid 43K for car 10K upgrades went from 2 minutes down to 12 seconds so I doubt it will take me another 50k to get to 10's:bigthumb:
Well... I don't know about humans but if my R/T can pull a 1/4 mile in 13.5 seconds on 373 HP, then in order for it to blaze across the line in 2 minutes I would only need .53HP. The question though really is, if I cut a horse in half would it weigh more or less than my engine? Also, can a horse run on only two legs?
 
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