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Discussion Starter · #1 ·
I have a .24 sec span of time from when I release the trans brake button and RPM's start to climb and the first rotation of the drive shaft. I have to roll deep into the pre-stage beam to cut a good light but will red light if staging completely 'deep'. I am thinking of increasing the RPM's on the two step to see if this decreases this delay but I have been told it is better to get a "run" at the converter. I currently have the two step at 3900 with a stall on the converter of 4600 and am curious to see if my reaction times will improve if I leave at 4400 RPM's.
 

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My car gets it's best 60' times when the 2-step is set 200 rpm's under the stall speed. Stalls at 6000 and the 2-step is set at 5800. Just snapped a 12 bolt 33 spline axle last night actually. The other one was twisted like mad! I really didn't expect this when the car only 60's at a 1.33-1.34.
 

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It sounds to me more like you have a poor trans brake. They make brakes with differnet release times. Todays fast pro brakes are very fast release. I run some 4/10s pro tree races and in most cars leaving at higher RPMs make you leave faster. If I leave at 6100 rpms I go red so I leave at lower RPMs depending on track conditions. RM
 

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I have the same problem. My t/brake is also slow as real mccoy stated above. I went to the track and I left as the last bulb lit and I cut my best light. It might just be a matter of knowing the car and leaving a little earlier. I left much earlier and I cut a .039 light on a .500 tree so that gives you an idea of how much more room I have to leave.
 

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Discussion Starter · #6 ·
.400 Pro Tree

I should have mentioned we run a 4 tenths Pro Tree. I have a Moroso button with an adjustable collar and an e-clip to limit the depression. It is set as fast as I can get it to react. I also spend lots of time on my practice tree, adjusting it with a .25 rollout I am red and .00's regularly so I know my car is moving slow. I am going to increase the two step. All excellent input so far, thanks to all replies, keep em coming.
 

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Increase the air in the front tires to the max you can stand. Run a smaller dia front tire. Tie the front end down if you can. Increase air in the slicks to the max that will work. Be sure you have no stagger in the front tires. Lots of ways to help a poor light. RM
 

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Discussion Starter · #8 ·
I am most interested in finding a reason, if any, why the lag time a from releasing the button and the first rotation of the drive shaft. I imagined the rpm's would shoot straight up to converter stall but they gradually climb from release of the transbrake to stall and on through the run. The obvious and final problem is of course a slower than desired reaction time, it just seems it takes too long for the energy to get though the car, load the car and then start moving. I am going to try and find a way to upload the graph.
 

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Our car does that all the time. Even with a .000 light and a 1.37 60' the difference between the G meter and driveshaft speed is almost 2 tenths of a second. A car should move quicker with the converter locked up then it does with a 2 step. The lower we go on the 2 step the worse the reaction time gets.
 
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