The discussion thread on 1/4 mile E.T. and Trap Speed, and their relationship to HP
#32
10-21-2006, 04:40 PM
Originally Posted by Jean
Scott, I am not debating the trap speed, which I know is true of course, what I am saying is that either trap speed means little in relation to Hp and there is much more to it or if this trap speed means 600HP, your car was not on stock K16s, this is physics not dynos or trap speeds.
Do you have the slip for that run, I would like to look at the acceleration between your 330ft and quartermile. Please PM if you wish.
BTW, you can check it out with Todd if you would like.
Do you have the slip for that run, I would like to look at the acceleration between your 330ft and quartermile. Please PM if you wish.
BTW, you can check it out with Todd if you would like.
Kevin
Last edited by KPG; 10-21-2006 at 04:44 PM.
#33
10-21-2006, 05:10 PM
KPG
That is not exactly what I meant on my post if this is what transpired. I have always preached that trap speed is a good indicator of HP, albeit not a very accurate one. It certainly gives a much better picture of HP that the ET, but I do think that 60ft times impact the trap speed as well, therefore represent an important variable.
Cheers
That is not exactly what I meant on my post if this is what transpired. I have always preached that trap speed is a good indicator of HP, albeit not a very accurate one. It certainly gives a much better picture of HP that the ET, but I do think that 60ft times impact the trap speed as well, therefore represent an important variable.
Cheers
#34
10-21-2006, 05:34 PM
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Originally Posted by KPG
Well , so much for the civil conversation. I asked for more info nothing less and you come unglued. Heck , I never even saw the threads Scott deleted, but they must have been keepers. Please email me your address, I will overnight my Racelogic to you tomorrow. Once again, this was a request for more info nothing more. If you post phenonemal numbers, I will shout your praises from the rooftops. I am still looking for where I talked down to you or your setup.I am still looking for where I stated mine was better.I am still looking for where I said 24's were automatically better. I am still looking for where I stated 600hp is impossible.This is not personal and you are missing the larger point...if you are making 600hp with stock K16's that is phenonmenal.I think I am barely making 600 and there are so many cars that will stomp my setup it isnt even funny. Good for you if have those numbers. Kevin
I'll use her and send her right back overnight. PM me if you're willing. I won't be able to put her on the dyno tomorrow, TPC said they have a car they are experimenting with all day tomorrow and the dyno wouldn't be available. They can be a little quirky sometimes. I'm still going to call and bug them again tomorrow to see it they will let me run her. Maybe some day next week.
#35
10-21-2006, 06:17 PM
Originally Posted by Divexxtreme
Let me give you an example of what I mean.
Here is a link to the timeslips of (3) 10 second runs I made with my car. You'll notice that the run with the highest trap speed (136) was also the run with the slowest E.T and slowest 60' time (10.86 & 1.85, repectively). I actually spun my tires and got wheelhop on that run, which is why I lost 2/10's of a second and had a slower 60' time.
Also look at the 1/8th mile mph. I only had 103 mph at the 1/8th on that run compared to 107 and 108 mph in the other two. But I still trapped the fastest mph on that run.
That's what I mean when I say that trap speed isn't really dependant on launch or even the 1/8th mile E.T/trap that much. It's relies on pure wheel HP once you reach the end of the 1/4, and nothing else.
https://www.6speedonline.com/forums/...0&d=1142120077
Here is a link to the timeslips of (3) 10 second runs I made with my car. You'll notice that the run with the highest trap speed (136) was also the run with the slowest E.T and slowest 60' time (10.86 & 1.85, repectively). I actually spun my tires and got wheelhop on that run, which is why I lost 2/10's of a second and had a slower 60' time.
Also look at the 1/8th mile mph. I only had 103 mph at the 1/8th on that run compared to 107 and 108 mph in the other two. But I still trapped the fastest mph on that run.
That's what I mean when I say that trap speed isn't really dependant on launch or even the 1/8th mile E.T/trap that much. It's relies on pure wheel HP once you reach the end of the 1/4, and nothing else.
https://www.6speedonline.com/forums/...0&d=1142120077
#36
10-21-2006, 07:30 PM
Originally Posted by 9Eleven
Hey Kevin, if Martin doesn't want to use it, send it to me. I would love to see what my chipped 2 runs now. I'll use her and send her right back overnight. PM me if you're willing. I won't be able to put her on the dyno tomorrow, TPC said they have a car they are experimenting with all day tomorrow and the dyno wouldn't be available. They can be a little quirky sometimes. I'm still going to call and bug them again tomorrow to see it they will let me run her. Maybe some day next week.
I'll use her and send her right back overnight. PM me if you're willing. I won't be able to put her on the dyno tomorrow, TPC said they have a car they are experimenting with all day tomorrow and the dyno wouldn't be available. They can be a little quirky sometimes. I'm still going to call and bug them again tomorrow to see it they will let me run her. Maybe some day next week.
#37
10-24-2006, 01:13 PM
Originally Posted by Jean
I don't disagree with trap speed and HP, it does need corrections for the launch, do you disagree with that?
I mean it is quite straightforward that if you cross the 60 feet mark at 65mph instead of 60mph, your trap speed will be higher, do you disagree? So two persons having the exact same car, one goes through the 60ft in 2.5 seconds and the other in 1.7 seconds...one traps at 120mph and the other 125mph, does it mean he has 100HP more??
If you agree with the numbers I posted on engine VE and turbo compressor sizes, there is no room for debate I would think? Todd builds your engines, you might want to double check with him. No need to take this personally.
I mean it is quite straightforward that if you cross the 60 feet mark at 65mph instead of 60mph, your trap speed will be higher, do you disagree? So two persons having the exact same car, one goes through the 60ft in 2.5 seconds and the other in 1.7 seconds...one traps at 120mph and the other 125mph, does it mean he has 100HP more??
If you agree with the numbers I posted on engine VE and turbo compressor sizes, there is no room for debate I would think? Todd builds your engines, you might want to double check with him. No need to take this personally.
Joe
#38
10-24-2006, 01:43 PM
Hi Joe,
I guess you are talking about the trap speed vs HP and not the maximum HP a K16 can provide.
What I am saying is that there is an instrinsic relaitonship between ET and trap speed, and since there is a relationship between 60FT and ET, then 60ft and trap speed are interrelated.
I have hardly any experience in drag racing unfortunately however I have not seen yet a mathematical proof that those 2 are not interrelated, and that trap speed is HP independently of 60Ft time (and ET). Don't know if it makes sense, but the example I gave earlier is math logic and motion dynamics.
Scott (or someone else) can you please let me know what formula do you guys use to establish that trap speed equals xxx HP?
Fascinating subject.
Joe... heard of a 150mph trap speed from Bellos...when is your car going to be ready? Cheers
Thanks.
I guess you are talking about the trap speed vs HP and not the maximum HP a K16 can provide.
What I am saying is that there is an instrinsic relaitonship between ET and trap speed, and since there is a relationship between 60FT and ET, then 60ft and trap speed are interrelated.
I have hardly any experience in drag racing unfortunately however I have not seen yet a mathematical proof that those 2 are not interrelated, and that trap speed is HP independently of 60Ft time (and ET). Don't know if it makes sense, but the example I gave earlier is math logic and motion dynamics.
Scott (or someone else) can you please let me know what formula do you guys use to establish that trap speed equals xxx HP?
Fascinating subject.
Joe... heard of a 150mph trap speed from Bellos...when is your car going to be ready? Cheers
Thanks.
Last edited by Jean; 10-24-2006 at 01:46 PM.
#39
10-24-2006, 02:04 PM
Hi Jean,
Actually, what I meant was the 60' time doesn't really have a very large effect on the 1320' trap speed like we would think it does. I've done very easy launches and hard launches with the same car and the final trap will almost always stay within 2mph or less. I would also have thought that if I was 5mph faster at the 60' point then I would carry that to the 1320' point but no, it just doesn't happen.
Yes, it's true that Bello's back out there with a car. He was at the NHRA race in Ca. this past weekend and did make one qualifing run at 150mph. I heard he was testing in Palm Beach and went 10.0 standing on the brakes so as not to break the 9's and get kicked off the track. I guess I had better get my *** moving and get my engine done? I'm sure I'll get a call from him soon?
Joe
Actually, what I meant was the 60' time doesn't really have a very large effect on the 1320' trap speed like we would think it does. I've done very easy launches and hard launches with the same car and the final trap will almost always stay within 2mph or less. I would also have thought that if I was 5mph faster at the 60' point then I would carry that to the 1320' point but no, it just doesn't happen.
Yes, it's true that Bello's back out there with a car. He was at the NHRA race in Ca. this past weekend and did make one qualifing run at 150mph. I heard he was testing in Palm Beach and went 10.0 standing on the brakes so as not to break the 9's and get kicked off the track. I guess I had better get my *** moving and get my engine done? I'm sure I'll get a call from him soon?
Joe
#40
10-24-2006, 04:41 PM
Originally Posted by Jean
What I am saying is that there is an instrinsic relaitonship between ET and trap speed, and since there is a relationship between 60FT and ET, then 60ft and trap speed are interrelated.
I have hardly any experience in drag racing unfortunately however I have not seen yet a mathematical proof that those 2 are not interrelated, and that trap speed is HP independently of 60Ft time (and ET). Don't know if it makes sense, but the example I gave earlier is math logic and motion dynamics.
I have hardly any experience in drag racing unfortunately however I have not seen yet a mathematical proof that those 2 are not interrelated, and that trap speed is HP independently of 60Ft time (and ET). Don't know if it makes sense, but the example I gave earlier is math logic and motion dynamics.
I posted some real-life examples earlier in this thread of how what you are talking about is not always the case. In case you accidentally missed it, here's the post:
https://www.6speedonline.com/forums/...3&postcount=45
#41
10-24-2006, 04:49 PM
Scott, thanks.
I did see them, but they do not prove to me that there is no correlation between 60ft and trap speed. I still see them interlinked to a certain point.
Do you have the formula to find HP based on trap speed that you use? That would help.
I did see them, but they do not prove to me that there is no correlation between 60ft and trap speed. I still see them interlinked to a certain point.
Do you have the formula to find HP based on trap speed that you use? That would help.
#42
10-24-2006, 05:08 PM
Originally Posted by Jean
Scott, thanks.
I did see them, but they do not prove to me that there is no correlation between 60ft and trap speed. I still see them interlinked to a certain point.
Do you have the formula to find HP based on trap speed that you use? That would help.
I did see them, but they do not prove to me that there is no correlation between 60ft and trap speed. I still see them interlinked to a certain point.
Do you have the formula to find HP based on trap speed that you use? That would help.
I've found this formula to be extremely accurate determining whp from trap speed. A friend of mine came up with it:
whp = wt. x (trap/234)^3/(1.057-(A/100,000)^3
Last edited by Divexxtreme; 10-25-2006 at 02:22 AM.
#43
10-24-2006, 05:22 PM
Scott
I am sure that in real life drag racing things are not black and white. But by saying that trap speed is related to horsepower we are saying that there is a mathematical equation that determines it... And you just posted it..
This formula (which is the same that I had) was found by Patrick Hale who is the authority in this sort of calculations. To put it in other form:
From the above posted formula you can get the trap speed by doing the following:
Trap speed = 234*(road HP/weight)^.3333
Also, in the same study Patrick Hale determined that :
1/4 ET = 5.825*(weight/road HP)^.3333
Therefore it is obvious that there is a direct correlation between ET and trap speed... in the form of :
ET = 1363/Trap Speed
This relationship is generic to all cars and as accurate as any of its components (real HP, real weight, temperature etc..) therefore one should expect some variances...
To correct it for Porsche cars (rear engine, weight distribution, aerodynamics....), you can use an adjustemnt of about 6.5% to make it:
ET = 1450/Trap Speed and take it from there.
This is not exact science, but it
1- proves that there is a direct correlation between ET and trap speed
2-Trap speed is influenced by how fast you go off the line
3- To know real HP based on trap speed you must adjust for point 2 above
4-Since there is a correlation between 60ft and ET, there is correlation between 60ft and trap speed as well.
Certainly real liofe experience is very important, but the motion study has some merits as well in highlighting how things work together. These findings are in sync of what I have seen on GPS datalogs during quartermile runs.
I might be mistaken but the logic seems to be quite conclusive based on the above. Any engineers here might be able to correct me if I am wrong..
This is why a rolling run is a more accurate indicator.
Cheers
I am sure that in real life drag racing things are not black and white. But by saying that trap speed is related to horsepower we are saying that there is a mathematical equation that determines it... And you just posted it..
This formula (which is the same that I had) was found by Patrick Hale who is the authority in this sort of calculations. To put it in other form:
From the above posted formula you can get the trap speed by doing the following:
Trap speed = 234*(road HP/weight)^.3333
Also, in the same study Patrick Hale determined that :
1/4 ET = 5.825*(weight/road HP)^.3333
Therefore it is obvious that there is a direct correlation between ET and trap speed... in the form of :
ET = 1363/Trap Speed
This relationship is generic to all cars and as accurate as any of its components (real HP, real weight, temperature etc..) therefore one should expect some variances...
To correct it for Porsche cars (rear engine, weight distribution, aerodynamics....), you can use an adjustemnt of about 6.5% to make it:
ET = 1450/Trap Speed and take it from there.
This is not exact science, but it
1- proves that there is a direct correlation between ET and trap speed
2-Trap speed is influenced by how fast you go off the line
3- To know real HP based on trap speed you must adjust for point 2 above
4-Since there is a correlation between 60ft and ET, there is correlation between 60ft and trap speed as well.
Certainly real liofe experience is very important, but the motion study has some merits as well in highlighting how things work together. These findings are in sync of what I have seen on GPS datalogs during quartermile runs.
I might be mistaken but the logic seems to be quite conclusive based on the above. Any engineers here might be able to correct me if I am wrong..
This is why a rolling run is a more accurate indicator.
Cheers
Last edited by Jean; 10-24-2006 at 05:31 PM.
#44
10-24-2006, 05:40 PM
Smokemup.com has some great calculators as well. They have one that gives you hp from E.T and another that gives hp from trap speed. But you can see that even they claim that the E.T. calculator is not accurate, but the trap speed calculator is very accurate.
http://www.smokemup.com/auto_math/index.php#hp
My point is, they admit that the E.T. calculator, which relies on the 60' time...can skew results. But the Trap Speed calculator doesn't use the 60' time as a variable.
http://www.smokemup.com/auto_math/index.php#hp
My point is, they admit that the E.T. calculator, which relies on the 60' time...can skew results. But the Trap Speed calculator doesn't use the 60' time as a variable.
Last edited by Divexxtreme; 10-25-2006 at 02:22 AM.
#45
10-24-2006, 05:47 PM
Scott, I agree with you (except that last sentence that I cannot read ) , these calculators can never be 100% accurate just because of the variables involved (traction, weight distribution, exact weight, exact hp and probably this is the biggest uknown, etc..), however I was just interested in the fact that they are interrelated, the number (1450) used might be a point of debate but nevertheless there exists a link between them as shown.
If you go to the drag thread, you will see that many of the cars shown can get quite close to the theoretical number... Of course some others don't, but quite accurate I think.. I am sure your run will throw off any theory to the garbage
) , these calculators can never be 100% accurate just because of the variables involved (traction, weight distribution, exact weight, exact hp and probably this is the biggest uknown, etc..), however I was just interested in the fact that they are interrelated, the number (1450) used might be a point of debate but nevertheless there exists a link between them as shown.If you go to the drag thread, you will see that many of the cars shown can get quite close to the theoretical number... Of course some others don't, but quite accurate I think.. I am sure your run will throw off any theory to the garbage