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My first 2 runs down the 1320 in the Vette

 
Old 11-20-2018, 08:22 AM
  #41  
Daddy Freeman
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I don't disagree with you at all. I know that I will not be getting the seat time needed to make that happen so I am going for the easy fix on the launch. I hope to make it to the track at least twice next year and I won't be as passive as I was on the 2nd and 3rd shifts since I know my hole shot will be right. I wish I had the time to go to the track but I simply don't. At this point, I don't want to be flat out embarrassed when I go for fun.
I feel you on the manual. Nothing like cruising at 65 and dropping into 3rd and getting pinned back to the seat. I live out in the country and we have open roads for miles!
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Old 11-20-2018, 10:59 AM
  #42  
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Originally Posted by Daddy Freeman View Post
I don't disagree with you at all. I know that I will not be getting the seat time needed to make that happen so I am going for the easy fix on the launch. I hope to make it to the track at least twice next year and I won't be as passive as I was on the 2nd and 3rd shifts since I know my hole shot will be right. I wish I had the time to go to the track but I simply don't. At this point, I don't want to be flat out embarrassed when I go for fun.
I feel you on the manual. Nothing like cruising at 65 and dropping into 3rd and getting pinned back to the seat. I live out in the country and we have open roads for miles!
It's really too bad that you can't get out more. Sounds like you really enjoy it.
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Old 11-20-2018, 01:19 PM
  #43  
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Originally Posted by rpmextra View Post
I don't believe those devices would help much for those who can launch properly without one. Maybe I'm hard headed but main reason I stayed manual was to say I'm the one in control. I like knowing I can always improve upon my times because I know I can launch harder or shift faster etc.
That old 1320/mph=et formula I posted suggests you have the potential to improve another .6 over that last video. I looked at the fastest C6's on the list at the top of the Drag Racing page, the automatic times posted (with the exception of 1) were within a tenth of the formula. The closest manual on that list was over by .35.

In the past, it took a lot of work to get a manual trans car's efficiency up anywhere near an automatic. Now that we are able to control the hit of the clutch, it's a lot easier. Now we can usually beat the automatics

Grant

Last edited by sr530; 11-20-2018 at 01:21 PM.
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Old 11-20-2018, 02:20 PM
  #44  
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Originally Posted by sr530 View Post
That old 1320/mph=et formula I posted suggests you have the potential to improve another .6 over that last video. I looked at the fastest C6's on the list at the top of the Drag Racing page, the automatic times posted (with the exception of 1) were within a tenth of the formula. The closest manual on that list was over by .35.

In the past, it took a lot of work to get a manual trans car's efficiency up anywhere near an automatic. Now that we are able to control the hit of the clutch, it's a lot easier. Now we can usually beat the automatics

Grant
Grant, I hear ya I do. Going auto is out of the equation.
But explain to me how that device would help anyone beyond a more consistent 60ft. After that moment it's doing nothing for you am I wrong?

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Old 11-20-2018, 05:07 PM
  #45  
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Originally Posted by rpmextra View Post
Grant, I hear ya I do. Going auto is out of the equation.
But explain to me how that device would help anyone beyond a more consistent 60ft. After that moment it's doing nothing for you am I wrong?
Hopefully this graph makes it easier to see how efficiently recovering launch energy can affect your ET...



Line A is drawn as an extension of the angle formed by the Erpm trace after the chassis has stabilized, basically representing what acceleration would have looked like with just max engine power alone accelerating the car from a dead stop.
Line B represents the actual average rate of acceleration rate with stored launch energy being recovered. In the above graph, efficiently recovering launch energy shaved roughly 1 second off the 60'.

When line A crosses the "0" line at 1/2 of launch rpm, I consider that pretty good. In this case line A crosses "0" at about 3400, so the launch was pretty efficient at recovering launch energy. I usually just hold a straight edge against my screen to see where it crosses instead of drawing the line.

Spinning a rotating assy up higher prior to the start makes more power available to accelerate the car when the clocks are running. The above 7300rpm launch stores over 3 times as much energy in the rotating assy over a 4000rpm launch. Without the ability to control the hit of the clutch, it would not have been possible to feed all the energy from a 7300rpm launch into the chassis without breaking the tires loose.

Note that the shifts on this graph still needed to be softened a bit, as that wheelspin after the shifts indicates the energy being released due to ratio change isn't being recovered as efficiently as possible.

Grant

Last edited by sr530; 11-20-2018 at 07:21 PM.
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Old 11-20-2018, 10:24 PM
  #46  
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Originally Posted by sr530 View Post
Hopefully this graph makes it easier to see how efficiently recovering launch energy can affect your ET...



Line A is drawn as an extension of the angle formed by the Erpm trace after the chassis has stabilized, basically representing what acceleration would have looked like with just max engine power alone accelerating the car from a dead stop.
Line B represents the actual average rate of acceleration rate with stored launch energy being recovered. In the above graph, efficiently recovering launch energy shaved roughly 1 second off the 60'.

When line A crosses the "0" line at 1/2 of launch rpm, I consider that pretty good. In this case line A crosses "0" at about 3400, so the launch was pretty efficient at recovering launch energy. I usually just hold a straight edge against my screen to see where it crosses instead of drawing the line.

Spinning a rotating assy up higher prior to the start makes more power available to accelerate the car when the clocks are running. The above 7300rpm launch stores over 3 times as much energy in the rotating assy over a 4000rpm launch. Without the ability to control the hit of the clutch, it would not have been possible to feed all the energy from a 7300rpm launch into the chassis without breaking the tires loose.

Note that the shifts on this graph still needed to be softened a bit, as that wheelspin after the shifts indicates the energy being released due to ratio change isn't being recovered as efficiently as possible.

Grant
It all makes sense now Grant. You are selling a product. Now I see your constant desire to sell me on your idea.
With all do respect, I like improving my driving skills and continue to see results rather than let a device take care off it. I am not competing with anyone and always striving to improve my driving skills. If your system works as good as you say it does.....what the hell do I have left lol. More time to wax the car I guess.
I am starting to believe your system works but I'm not about to think that with it i'd be running 9.26 with my car because of it. I think there is definitly .20 on the table untouched. But the other 0.40 would have the internet explode.
Because you didn't answer my question directly I'll word it differently. After the launch (i understand mechanically whats beneficial) there is still shift speed, gear ratios, power under and over the curve etc. does your system helps anywhere else other than the launch? I see you mentioned softened shifts.


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Old 11-20-2018, 11:53 PM
  #47  
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Originally Posted by sr530 View Post
Hopefully this graph makes it easier to see how efficiently recovering launch energy can affect your ET...



Line A is drawn as an extension of the angle formed by the Erpm trace after the chassis has stabilized, basically representing what acceleration would have looked like with just max engine power alone accelerating the car from a dead stop.
Line B represents the actual average rate of acceleration rate with stored launch energy being recovered. In the above graph, efficiently recovering launch energy shaved roughly 1 second off the 60'.

When line A crosses the "0" line at 1/2 of launch rpm, I consider that pretty good. In this case line A crosses "0" at about 3400, so the launch was pretty efficient at recovering launch energy. I usually just hold a straight edge against my screen to see where it crosses instead of drawing the line.

Spinning a rotating assy up higher prior to the start makes more power available to accelerate the car when the clocks are running. The above 7300rpm launch stores over 3 times as much energy in the rotating assy over a 4000rpm launch. Without the ability to control the hit of the clutch, it would not have been possible to feed all the energy from a 7300rpm launch into the chassis without breaking the tires loose.

Note that the shifts on this graph still needed to be softened a bit, as that wheelspin after the shifts indicates the energy being released due to ratio change isn't being recovered as efficiently as possible.

Grant
i agree with you on keeping the energy at the launch is key, which is why Ive found the best 60s from accelerating into the launch rather than holding it at 4K and letting the clutch out. I learned to release the clutch after many passes to find the sweet spot between too slow and burning up the clutch and too fast and bogging.

What is is this device and how do you install it? Ls1 cars had a restriction in the clutch line, is this what it is?

Speeding the learning process would have value for those that dont have time or desire to do the passes it takes to learn it.

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Old 11-21-2018, 01:49 AM
  #48  
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Originally Posted by rpmextra View Post
Because you didn't answer my question directly I'll word it differently. After the launch (i understand mechanically whats beneficial) there is still shift speed, gear ratios, power under and over the curve etc. does your system helps anywhere else other than the launch? I see you mentioned softened shifts.
Quicker shifts by effectively shortening pedal travel while making a pass, as the pedal won't have enough time to return all the way back to the top before it's time for the next shift. It also adds a limited amount of clutch slip after WOT shifts, as the pedal returns instantly to that sweet spot zone where limited slip occurs. That raises recovery rpm and effectively adds area under the curve.

Grant
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Old 11-21-2018, 02:06 AM
  #49  
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Originally Posted by Joe_G View Post
i agree with you on keeping the energy at the launch is key, which is why Ive found the best 60s from accelerating into the launch rather than holding it at 4K and letting the clutch out. I learned to release the clutch after many passes to find the sweet spot between too slow and burning up the clutch and too fast and bogging.

What is is this device and how do you install it? Ls1 cars had a restriction in the clutch line, is this what it is?

Speeding the learning process would have value for those that dont have time or desire to do the passes it takes to learn it
This one is an external hyd cylinder that allows your foot to instantly release the pedal to a precise point within the sweet spot zone. From that point on, pedal travel is slowed to extend the time spent in that sweet spot zone. The current versions are typically installed between the clutch pedal and a dash bracket. There are two control adjustments, one for where in the pedal's travel that travel delay becomes active, and another for how long the pedal remains within that sweet spot zone.

Grant
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Old 11-21-2018, 05:41 PM
  #50  
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Originally Posted by sr530 View Post
This one is an external hyd cylinder that allows your foot to instantly release the pedal to a precise point within the sweet spot zone. From that point on, pedal travel is slowed to extend the time spent in that sweet spot zone. The current versions are typically installed between the clutch pedal and a dash bracket. There are two control adjustments, one for where in the pedal's travel that travel delay becomes active, and another for how long the pedal remains within that sweet spot zone.

Grant
I could see that being very useful for someone starting out and I'm sure does a better job than the "launch control" that comes on the later cars.
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Old 11-21-2018, 06:39 PM
  #51  
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Originally Posted by sr530 View Post
This one is an external hyd cylinder that allows your foot to instantly release the pedal to a precise point within the sweet spot zone. From that point on, pedal travel is slowed to extend the time spent in that sweet spot zone. The current versions are typically installed between the clutch pedal and a dash bracket. There are two control adjustments, one for where in the pedal's travel that travel delay becomes active, and another for how long the pedal remains within that sweet spot zone.

Grant
And how would an average driver without tons of runs and data aquisition overlays, formulas, etc set this device up to work properly and maximize effectiveness? Once dialed in does it need to be adjusted if you add more power, track comditions, tire pressure, etc? Or is it a set it and forget it type deal?
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Old 11-21-2018, 07:33 PM
  #52  
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Originally Posted by Huncle J View Post


And how would an average driver without tons of runs and data aquisition overlays, formulas, etc set this device up to work properly and maximize effectiveness? Once dialed in does it need to be adjusted if you add more power, track comditions, tire pressure, etc? Or is it a “set it and forget it” type deal?
If you don't have data, just make a couple test hits to get the hit adjustment in the ballpark. If the tires don't spin, add a turn of adjustment and make another hit. When you reach the point where the tires spin, back off slightly. At the track, timeslips are your data. Just keep adding 1 turn of hit per pass until the timeslips stop improving.

A clutch hit controller matches the hit of the clutch to the engine's power. Engine's power usually doesn't change much unless maybe you have a dual mode setup, like a nitrous application that also likes to make passes NA, that will likely require two different hit adjustments. Tires won't need pressure adjustments as the goal is dead hooking, not controlled spin. Serious racers looking for the last couple percent typically have hit/traction tuned right to the edge, they may make slight adjustments as the track changes. No need to unhook the device for casual driving.

Grant

Last edited by sr530; 11-21-2018 at 07:33 PM.
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Old 12-03-2018, 08:38 AM
  #53  
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Went back out Friday (11-30-18) and got 5 runs in. It was warm (low70s) and very humid. DA was 2200-2400 range.

Started the night launching at 3500 and bogging hard. Worked up to 4500 and still bogged. Started at 24psi for runs 1 and 2 then dropped to 22. By end of the night I was trying to spin off the line without dumping the clutch to try and find the limit but still not trying to puke my diff bits onto the track

best run was #3 with a 12.29 @ 116 with a 1.95 60. Windshield fogged up bad so immediately dropped windows after finish.

Run 4 burnout felt weird. As I let off brakes and rolled out it felt like it kept spinning when I felt it should have hooked already. Felt like I spun off the line (or clutch was slipping) but I just stayed in it and when I went for 2nd, the clutch was still on the floor (didnt have time to ranger flush before I went out)




Last edited by Huncle J; 12-03-2018 at 09:02 AM.
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Old 04-13-2019, 10:39 AM
  #54  
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Default First time out 2019 season

Finally got back to the local track (Alamo City Motorplex in San Antonio TX) and got 4 runs in. DA was around 2440 based off air density online. Didnt both taking video, but wish I had.

First run was a 12.33 with a 1.9 60. 2nd run was a new personal best 12.03 with a 1.8 60. I actually killed it doing a burnout (usually heel/toe but tried snapping foot off clutch over to brake and got too much and it died). Restarted but dont remember if I turned off tc or not. Last 2 runs chasing an 11 were both 12.2x with 1.9 60.

Happy with the consistency and new PB despite less than ideal air (previous best was 12.22 run at Houston with 800-900 DA). Would have liked to get an 11 in the books but it will come, just gotta get that launch down.

So this is new PB 60 1/8 and 1/4 et. Trap is down about 2mph though. Had 1/2 tank of gas


Last edited by Huncle J; 04-13-2019 at 01:25 PM.
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Old 04-14-2019, 01:15 AM
  #55  
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Man so so close to that 11.9x pass, but I bet you still had a goofy smile for a bit lol.
Great work and nice to get an update
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Old 04-14-2019, 04:11 PM
  #56  
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Awesome Huncie J! Nice to see you perfecting your craft. Its fun to practice and get better.
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Old 04-15-2019, 02:27 PM
  #57  
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Thanks guys! What kind of 60 is reasonable with my set up? I am thinking 1.5x to 1.7x... more power and gears would help a lot but that isnt in the cards (credit) right now...lol
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Old 04-15-2019, 08:00 PM
  #58  
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Originally Posted by Huncle J View Post
Thanks guys! What kind of 60 is reasonable with my set up? I am thinking 1.5x to 1.7x... more power and gears would help a lot but that isnt in the cards (credit) right now...lol
1.7, yes, 1.6, with some work. 1.5 will be a bit tough without gears and using a stock clutch.
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Old 04-17-2019, 11:51 AM
  #59  
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Originally Posted by Joe_G View Post
1.7, yes, 1.6, with some work. 1.5 will be a bit tough without gears and using a stock clutch.
Thank you. I need to talk to some other drivers out there and see what kind of 60 they are cutting. I think it is worse than u would expect at another track. I vaguely remember a GTR on drag radials not having super impressive 60s and I thought that was weird.

How much gas did u typically have when u got best results? I am thinking 1/4 tank.
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Old 04-17-2019, 07:15 PM
  #60  
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Originally Posted by Huncle J View Post
Thank you. I need to talk to some other drivers out there and see what kind of 60 they are cutting. I think it is worse than u would expect at another track. I vaguely remember a GTR on drag radials not having super impressive 60s and I thought that was weird.

How much gas did u typically have when u got best results? I am thinking 1/4 tank.
Yes, tank or less. We had pumps at the track which was handy.
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