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All Around Great Guy
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Discussion Starter #1
Just started having fun running at the track last year. I ran a 15.6 which is ok, but my trap speed could not get over 85mph. Is that a lack of hp at the end of my powerband? What mods would give me a higher trap speed? I see times of trucks that are very close(et) but the trap speed is higher. I always wondered why and how this is. If both are almost identical et's and the trap speed is 5mph higher or lower, does one have more torque and gets ahead but does not have the power and the other vehicle catches it at the end with more hp?
 

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i would say grab the long tubes and the cutout and youll gain some miles per hour in the trap
 

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hemi1569 said:
Just started having fun running at the track last year. I ran a 15.6 which is ok, but my trap speed could not get over 85mph. Is that a lack of hp at the end of my powerband? What mods would give me a higher trap speed? I see times of trucks that are very close(et) but the trap speed is higher. I always wondered why and how this is. If both are almost identical et's and the trap speed is 5mph higher or lower, does one have more torque and gets ahead but does not have the power and the other vehicle catches it at the end with more hp?
ET and trap speed, in general, trap speed is an indication of horsepower (combined with vehicle weight), while ET is a combination of power and traction. So with identical ET's and 5mph difference in trap speed the first thing I would look at is traction getting off the line. For example, truck A runs 15.6 @ 90, with a 2.4 60ft. Truck B runs 15.6 @ 85 with a 2.1 60ft. All else being equal, truck A has more power but had trouble getting off the line.
Also a note on HP and torque. HP is simply a function of torque and RPM. The forumula is HP = (torque x RPM) / 5252.
It is possible for two identical weight vehicles with very similar peak power ratings (say 300 hp) to have different trap speeds based on a difference in the average hp over the rpm range used. Throw in different gearing and the difference can be even more dramatic. But just a quick example.
Truck A is rated from the factory at 300hp, but has a high revving motor that doesn't make full power until 5,500 rpm, shifting at 5,800. Let's say that at 3,500 rpm this motor makes 200 hp.
Truck B is also rated at 300 hp, but has a larger motor and makes its full power at 4,500 rpm, shifting at 5,000. At 3,500 rpm this motor may make 250 hp.
So as you can see, accelerating from idle (again, all else being equal), truck B will accelerate faster through the mid-range, but have to shift gears sooner. So you could see the advantage passing from one truck to the other at different points on the track.
Hope this helps and doesn't confuse more!

-Austin
 

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Hemi2nV
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austin9350 said:
ET and trap speed, in general, trap speed is an indication of horsepower (combined with vehicle weight), while ET is a combination of power and traction. So with identical ET's and 5mph difference in trap speed the first thing I would look at is traction getting off the line. For example, truck A runs 15.6 @ 90, with a 2.4 60ft. Truck B runs 15.6 @ 85 with a 2.1 60ft. All else being equal, truck A has more power but had trouble getting off the line.
Also a note on HP and torque. HP is simply a function of torque and RPM. The forumula is HP = (torque x RPM) / 5252.
It is possible for two identical weight vehicles with very similar peak power ratings (say 300 hp) to have different trap speeds based on a difference in the average hp over the rpm range used. Throw in different gearing and the difference can be even more dramatic. But just a quick example.
Truck A is rated from the factory at 300hp, but has a high revving motor that doesn't make full power until 5,500 rpm, shifting at 5,800. Let's say that at 3,500 rpm this motor makes 200 hp.
Truck B is also rated at 300 hp, but has a larger motor and makes its full power at 4,500 rpm, shifting at 5,000. At 3,500 rpm this motor may make 250 hp.
So as you can see, accelerating from idle (again, all else being equal), truck B will accelerate faster through the mid-range, but have to shift gears sooner. So you could see the advantage passing from one truck to the other at different points on the track.
Hope this helps and doesn't confuse more!

-Austin
Good read and a good first post. Welcome to Dodgetalk Austin :rck:
 

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HemiSS/T
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DAMN!!! I like reading stuff liek that. Liste=nign to people who knwo what they are seriously talking about is amazing. Everytime I log in I seem to gain more respect for everybody in here and their knowledge. Good job Austin welcome.
 

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Your time is pretty close to what I run. I am in the Coca Cola lane.
Check out your 60', your 330' and your 1/8 against mine and see how close you are to mine. I am 4/100ths and a little over 1 mile an hour faster.
 

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you redlighted.
 

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All Around Great Guy
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Discussion Starter #8
I know my best 60 was a 2.275, i dunno about my 330, my 1/8 was a 10.07 at 70mph and 15.6 at 85.68 I lost my slip or someone threw it out!
 

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All Around Great Guy
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I was running I believe 25 psi in the rears and did not touch the fronts. Took tailgate off and did not affect time neg or pos(time was different but not significant). Mirrors out, spare on. Was basically looking to hit 14.0 at 95+ and am willing to pay a little
 

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To cut 1.5 seconds off you are going to pay. About the only thing I can see you do to get that kinda time off is a baby bottle.
 

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All Around Great Guy
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Discussion Starter #12
Mifjac is running 13.9 with n/a but he is 2wd. If I had more mods than him, i would not be able to hit that?
 

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You'll have to go above and beyond what a 2wd does due to your weight. Dont worry i'm in the same weight bracket as you being we have the same trucks. But it's always nice to have the 4WD when needed.
 

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Ram3500Dually said:
you pulled a .306 RT i'm willing to bet it was a .500 tree. You redlighted.
 

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Hemi5spd said:
you pulled a .306 RT i'm willing to bet it was a .500 tree. You redlighted.
Don't bet the farm on that, you'll loose, LOL

Grand Bend for some reason runs an .000 tree. Its about the only track I have ever been to that runs it.
 

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Hemi2nV
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Hemi5spd said:
you pulled a .306 RT i'm willing to bet it was a .500 tree. You redlighted.
Not all tree are a .500, the one at my track is a .000. and if you readlight it is a negative number. So Dually might of just had a good time. Beside the r/t doesnt factor into your e/t
 

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Here is a full scan of the time slip. Look at the bottom, right lane wins. They use the Compulink Autostart.

You may have to click on the timeslip to see it larger if its a thumbnail.
 

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Hemi2nV
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Ram3500Dually said:
Here is a full scan of the time slip. Look at the bottom, right lane wins. They use the Compulink Autostart.

You may have to click on the timeslip to see it larger if its a thumbnail.
Thats one fast dually. My dads friend want to race me in his duramax but i just laugh at him. I know he doesnt have a chance but I would like to see how he does.
 

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If the Duraslug has a chip he will probably spank you. I watched a stock Duraslug with just a Quadzilla chip added run a 14.80 1/4
 

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If he has the Edge box.... well lets just say your in trouble.


Duramax + Edge = low 14.xx ET's =0)
 
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