Roll racing question
jeepgclwj
08-04-2009, 10:56 AM
I made a statement somewhere that trap speeds have nothing to do with a roll race from 60-120 when both cars racing only trap at 103. Was I wrong in saying that because I opened up a big ass can with that statement.
VR43000GT
08-04-2009, 01:34 PM
I really don't do a whole lot of roll racing but if each car traps identical speeds it is going to be somewhat similar. The only thing is, is that low end power is used for part of the 1/4 mile too as oppose to a 60-120 roll run which is going to be staying in the top end power. Therefore a car with better low end power but not quite as much top end power could trap as high as the car with less low end power but has a little more top end power and vice versa.
jeepgclwj
08-04-2009, 01:42 PM
I hear what your saying and agree but...
If you have a TBSS and a C5 Vette trap the same in the 1/4 mile I guess they should still be pretty much side by side at 160 mph.
Im using these 2 cars as an example. It could be any 2 cars that differ in more ways then just aerodynamics.
If I raced a 05+Mustang from 45-115 in my TA and put 2 cars on him by 115 and was still slowly pulling showing me that it would have gotten worse for him had we kept going BUT we trap the same in the 1/4. Shouldnt we be side by side and me not up by 2 because we trap the same.
At that point my story sounds made up and the bullshit flag should be thrown...
Amirite?
If you have a TBSS and a C5 Vette trap the same in the 1/4 mile I guess they should still be pretty much side by side at 160 mph.
Im using these 2 cars as an example. It could be any 2 cars that differ in more ways then just aerodynamics.
If I raced a 05+Mustang from 45-115 in my TA and put 2 cars on him by 115 and was still slowly pulling showing me that it would have gotten worse for him had we kept going BUT we trap the same in the 1/4. Shouldnt we be side by side and me not up by 2 because we trap the same.
At that point my story sounds made up and the bullshit flag should be thrown...
Amirite?
-The Stig-
08-04-2009, 02:05 PM
Hmm, are the cars identical?
If they both trap 103mph in the 1/4, which one is getting there first? (quickest ET)
Whichever car has the better performance might be the one winning in a 60-120mph sprint even if it only hits 103mph in the trap.
Such as, say a 2001 6-speed LS1 Camaro... say it's hitting 103-104mph consistently. And say it's racing a 2005-2009 Mustang GT that's hitting the same traps. The LS1 has a bit more power, so in a 60-120 race it'll probably get there a bit quicker have a bit more torque and an extra gear. Also helps that the LS1 car has a bit more aero friendly design rather than a blocky front end.
Despite all that, the cars in our imaginary race are running similar times, but up top... the LS1 should be the faster one.
Of course you can have two cars run the same traps, but have drastically different ET's. For instance, a common time for a stock LS1 Fbody is say 13.8-14.0 and trap in the 103-105mph range, back in the day when I had my LS1 Fbody I took it to the track with a bad clutch and got 14.4 @ 105mph.
I would tend to agree that trap speed means everything in a roll race, that shows how fast your car is... but if the traps are very similar between two cars it'll probably come down to how they get there and how they're powered.
Not even sure if that makes any sense, or if it's even remotely correct but that's how I take it... and I take everything I say with a grain of salt as it is... :P
If they both trap 103mph in the 1/4, which one is getting there first? (quickest ET)
Whichever car has the better performance might be the one winning in a 60-120mph sprint even if it only hits 103mph in the trap.
Such as, say a 2001 6-speed LS1 Camaro... say it's hitting 103-104mph consistently. And say it's racing a 2005-2009 Mustang GT that's hitting the same traps. The LS1 has a bit more power, so in a 60-120 race it'll probably get there a bit quicker have a bit more torque and an extra gear. Also helps that the LS1 car has a bit more aero friendly design rather than a blocky front end.
Despite all that, the cars in our imaginary race are running similar times, but up top... the LS1 should be the faster one.
Of course you can have two cars run the same traps, but have drastically different ET's. For instance, a common time for a stock LS1 Fbody is say 13.8-14.0 and trap in the 103-105mph range, back in the day when I had my LS1 Fbody I took it to the track with a bad clutch and got 14.4 @ 105mph.
I would tend to agree that trap speed means everything in a roll race, that shows how fast your car is... but if the traps are very similar between two cars it'll probably come down to how they get there and how they're powered.
Not even sure if that makes any sense, or if it's even remotely correct but that's how I take it... and I take everything I say with a grain of salt as it is... :P
jeepgclwj
08-04-2009, 03:05 PM
Hmm, are the cars identical?
If they both trap 103mph in the 1/4, which one is getting there first? (quickest ET)
Whichever car has the better performance might be the one winning in a 60-120mph sprint even if it only hits 103mph in the trap.
Such as, say a 2001 6-speed LS1 Camaro... say it's hitting 103-104mph consistently. And say it's racing a 2005-2009 Mustang GT that's hitting the same traps. The LS1 has a bit more power, so in a 60-120 race it'll probably get there a bit quicker have a bit more torque and an extra gear. Also helps that the LS1 car has a bit more aero friendly design rather than a blocky front end.
Despite all that, the cars in our imaginary race are running similar times, but up top... the LS1 should be the faster one.
Of course you can have two cars run the same traps, but have drastically different ET's. For instance, a common time for a stock LS1 Fbody is say 13.8-14.0 and trap in the 103-105mph range, back in the day when I had my LS1 Fbody I took it to the track with a bad clutch and got 14.4 @ 105mph.
I would tend to agree that trap speed means everything in a roll race, that shows how fast your car is... but if the traps are very similar between two cars it'll probably come down to how they get there and how they're powered.
Not even sure if that makes any sense, or if it's even remotely correct but that's how I take it... and I take everything I say with a grain of salt as it is... :P
The way I see it, once the 2 cars exceed their 1/4 mile trap speeds during a race it means nothing what their 1/4 mile times are because they are going above it.
If you are roll racing from down low and up to the trap speed of the 2 cars or a hair past it then I can see using 1/4 mile times to determine outcomes during roll races. Roll races are usually top end runs so 1/4 trap times shouldnt even be considered on higher end runs.
Maybe I am dumb...
If they both trap 103mph in the 1/4, which one is getting there first? (quickest ET)
Whichever car has the better performance might be the one winning in a 60-120mph sprint even if it only hits 103mph in the trap.
Such as, say a 2001 6-speed LS1 Camaro... say it's hitting 103-104mph consistently. And say it's racing a 2005-2009 Mustang GT that's hitting the same traps. The LS1 has a bit more power, so in a 60-120 race it'll probably get there a bit quicker have a bit more torque and an extra gear. Also helps that the LS1 car has a bit more aero friendly design rather than a blocky front end.
Despite all that, the cars in our imaginary race are running similar times, but up top... the LS1 should be the faster one.
Of course you can have two cars run the same traps, but have drastically different ET's. For instance, a common time for a stock LS1 Fbody is say 13.8-14.0 and trap in the 103-105mph range, back in the day when I had my LS1 Fbody I took it to the track with a bad clutch and got 14.4 @ 105mph.
I would tend to agree that trap speed means everything in a roll race, that shows how fast your car is... but if the traps are very similar between two cars it'll probably come down to how they get there and how they're powered.
Not even sure if that makes any sense, or if it's even remotely correct but that's how I take it... and I take everything I say with a grain of salt as it is... :P
The way I see it, once the 2 cars exceed their 1/4 mile trap speeds during a race it means nothing what their 1/4 mile times are because they are going above it.
If you are roll racing from down low and up to the trap speed of the 2 cars or a hair past it then I can see using 1/4 mile times to determine outcomes during roll races. Roll races are usually top end runs so 1/4 trap times shouldnt even be considered on higher end runs.
Maybe I am dumb...
VR43000GT
08-04-2009, 06:15 PM
You also have to realize when you are talking about 2 car lengths @ 160mph there is only about .01-03 of a second difference there I would guess which is really nothing. 2 car lengths ahead by 160mph is practically a tie.
jeepgclwj
08-04-2009, 07:32 PM
You also have to realize when you are talking about 2 car lengths @ 160mph there is only about .01-03 of a second difference there I would guess which is really nothing. 2 car lengths ahead by 160mph is practically a tie.
Would a 2 car lead from 45-115 be considered practically a tie between 2 cars that trap the same in the 1/4? Or would that be considered a good beating?
Would a 2 car lead from 45-115 be considered practically a tie between 2 cars that trap the same in the 1/4? Or would that be considered a good beating?
VR43000GT
08-05-2009, 02:52 PM
If you are behind by 2 car lengths at 115mph you are behind 2 car lengths regardless what you trap. In this case, the TBSS is going to severly suffer at high speeds far more than say the Corvette would. If you are wondering exactly how long 2 car lengths behind someone is @ 115mph (assuming both are going the same speed which if that was the case they would be going at a very similar rate of speed).
A Corvette is 179.7" or 14.975'
If going by 2 car lengths off of the measurement of the Corvette just for the sake of having something to go off of you would be 29.95' behind the winning car's front bumper.
So, to figure this out you would take 115mph and find out how many fph (feet per hour) that is which is 607,200 fph (5,280ft x 115mph). After this, you need to convert that fph to fps so we get 168.67fps (607,200fph/60minutes in a hour/60 seconds in a minute).
Now that we know that each car is moving roughly 168.67fps and that the losing car is 29.95ft behind the winning car. By taking 29.95ft/168.67fps we find that the losing car is .177 of a second behind the winning car.
A Corvette is 179.7" or 14.975'
If going by 2 car lengths off of the measurement of the Corvette just for the sake of having something to go off of you would be 29.95' behind the winning car's front bumper.
So, to figure this out you would take 115mph and find out how many fph (feet per hour) that is which is 607,200 fph (5,280ft x 115mph). After this, you need to convert that fph to fps so we get 168.67fps (607,200fph/60minutes in a hour/60 seconds in a minute).
Now that we know that each car is moving roughly 168.67fps and that the losing car is 29.95ft behind the winning car. By taking 29.95ft/168.67fps we find that the losing car is .177 of a second behind the winning car.
jeepgclwj
08-05-2009, 03:59 PM
If you are behind by 2 car lengths at 115mph you are behind 2 car lengths regardless what you trap. In this case, the TBSS is going to severly suffer at high speeds far more than say the Corvette would. If you are wondering exactly how long 2 car lengths behind someone is @ 115mph (assuming both are going the same speed which if that was the case they would be going at a very similar rate of speed).
A Corvette is 179.7" or 14.975'
If going by 2 car lengths off of the measurement of the Corvette just for the sake of having something to go off of you would be 29.95' behind the winning car's front bumper.
So, to figure this out you would take 115mph and find out how many fph (feet per hour) that is which is 607,200 fph (5,280ft x 115mph). After this, you need to convert that fph to fps so we get 168.67fps (607,200fph/60minutes in a hour/60 seconds in a minute).
Now that we know that each car is moving roughly 168.67fps and that the losing car is 29.95ft behind the winning car. By taking 29.95ft/168.67fps we find that the losing car is .177 of a second behind the winning car.
My head just exploded...:biggrin:
A Corvette is 179.7" or 14.975'
If going by 2 car lengths off of the measurement of the Corvette just for the sake of having something to go off of you would be 29.95' behind the winning car's front bumper.
So, to figure this out you would take 115mph and find out how many fph (feet per hour) that is which is 607,200 fph (5,280ft x 115mph). After this, you need to convert that fph to fps so we get 168.67fps (607,200fph/60minutes in a hour/60 seconds in a minute).
Now that we know that each car is moving roughly 168.67fps and that the losing car is 29.95ft behind the winning car. By taking 29.95ft/168.67fps we find that the losing car is .177 of a second behind the winning car.
My head just exploded...:biggrin:
AMGalltheway
08-05-2009, 06:07 PM
Holy Shit!! Math!!
-The Stig-
08-06-2009, 11:25 AM
Who the hell does Math these days?
Witchery... Heretic!
BURN HIM!!!
Witchery... Heretic!
BURN HIM!!!
TorchedStealth
08-08-2009, 08:16 PM
SL that was some damn witchcraft you just pulled lol.
Jeep, what was each of your 60' times since you trapped the same? I would bet yours was better than his. Back when I was stock I ran a turbo 300zx at the track. He was on slicks or radials and nailed a 1.9 60' while I spun and got a crappy 2.4 60'. The whole run he was pulling pretty good and he trapped 98mph. I ended up trapping 99.4mph. The difference is that he had a 13.9 or something et to my 14.8. He was clearly faster even though i trapped higher. This is quite an extreme example but I'll try to get my point across clearer.
Let's say the mustang was spinning more than you off the launch, it would give him more time to pick up speed to trap higher. If you nail a good solid run with minimal spinning there is less speed being picked up since your actually getting your power to the ground.
Its hard to explain, but next time you go to the track if you want to experiment launch really hard and make sure you spin bad. I bet you will run slower but trap at least 2mph higher than most of your runs.
Jeep, what was each of your 60' times since you trapped the same? I would bet yours was better than his. Back when I was stock I ran a turbo 300zx at the track. He was on slicks or radials and nailed a 1.9 60' while I spun and got a crappy 2.4 60'. The whole run he was pulling pretty good and he trapped 98mph. I ended up trapping 99.4mph. The difference is that he had a 13.9 or something et to my 14.8. He was clearly faster even though i trapped higher. This is quite an extreme example but I'll try to get my point across clearer.
Let's say the mustang was spinning more than you off the launch, it would give him more time to pick up speed to trap higher. If you nail a good solid run with minimal spinning there is less speed being picked up since your actually getting your power to the ground.
Its hard to explain, but next time you go to the track if you want to experiment launch really hard and make sure you spin bad. I bet you will run slower but trap at least 2mph higher than most of your runs.
CassiesMan
08-09-2009, 02:23 AM
Gearing, aerodynamics, weight. The roll side of racing they are.
TorchedStealth
08-10-2009, 12:41 AM
The roll side of racing they are.
Yoda? Lol
Yoda? Lol
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