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Cutting lights

Posted By: PolyDart

Cutting lights - 02/26/12 08:59 PM

Been having a terrible time being consistent at the line. Leave on the yellow, and I red light. Leave on the green and it's way to slow.

I try to pause a bit after the yellow, and my reactions are all over the place. Anything from a .009 to a .2!

I run a small 24" tire due to my fenderwell headers and I've heard that could have something to do with it.

Car runs in the 10.30s and 60fts at 1.44. Leave off idle on the footbrake.

Any advice would be greatly appreciated.
Posted By: cagebob1

Re: Cutting lights - 02/26/12 09:08 PM

Your reaction time should be just that...a reaction to something on the tree. Reactions tend to be consistent, while thinking isn't. Find a spot on the tree where your lights are consistent, then adjust the car till the time is what you want. On all of my race cars changing stage rpms was the easy way to do it.
Posted By: Leigh

Re: Cutting lights - 02/26/12 09:13 PM

Good advice, to change the car, not you. Find the place on the tree, where you are golden, then change the car to suit. Try the other way around, and you'll soon have a legion of vultures following you to staging. You might find a delay class WAY cheaper in the long run, HOWEVER, the competition will probably much tougher, too. Good luck.
Posted By: bonefish

Re: Cutting lights - 02/26/12 09:20 PM

Quit acting like me.
Posted By: VernMotor

Re: Cutting lights - 02/26/12 10:37 PM

YES find your spot on the tree. and change the car reaction time..Can't say this to many times ! and from day to day you will change. need to learn to change the car for that day ! all kinds of ways to change the car.
Posted By: PolyDart

Re: Cutting lights - 02/26/12 11:36 PM

Ok, let's say I want to leave on the last yellow. Other than a delay box, how would I slow down the car's reaction?

I did read where one of you said staging RPMS, but leaving off idle should give the slowest reaction since the engine has to come up on power, the suspension has to load, etc... I may be mistaken, but I would think I am already setting the car on the slow end of reaction.
Posted By: moparacer

Re: Cutting lights - 02/26/12 11:40 PM

Well lets throw the leaving on the green out the window first. That will always bee too slow no matter what.

If you have 60 fts in the mid 1.40's you should be able to leave at the flash of the 3rd amber and not go red leaving at a dead idle.

That's another thing.....I have never been able to get a car to react consistently leaving at an idle foot braking.

You need some RPM to tighten the drive line and suspension up before you leave.

Try 2000 RPM and see how it works. If you RT is slow go up in RPM and vice versa if its too quick.

What you have to be careful of is not to anticipate the 3rd coming on. You need to leave when it comes on.


Posted By: Triple Threat

Re: Cutting lights - 02/26/12 11:44 PM

The short front tire isn't ideal, but you should be able to make it work. The biggest issue is you. Go buy a practice tree and use it, you will improve.
Posted By: moparacer

Re: Cutting lights - 02/26/12 11:46 PM

Quote:

Ok, let's say I want to leave on the last yellow. Other than a delay box, how would I slow down the car's reaction?

I did read where one of you said staging RPMS, but leaving off idle should give the slowest reaction since the engine has to come up on power, the suspension has to load, etc... I may be mistaken, but I would think I am already setting the car on the slow end of reaction.



If you are going red leaving the line at a dead idle you are anticipating the 3rd light coming on.
Posted By: PolyDart

Re: Cutting lights - 02/26/12 11:48 PM

Quote:

You need some RPM to tighten the drive line and suspension up before you leave.

Try 2000 RPM and see how it works. If you RT is slow go up in RPM and vice versa if its too quick.





You're probably right. When initially working with the car I was all about best ET, now I have to forget that and work on best reaction times so I can go some rounds. The car definitely ETs best off idle, but it makes sense that it would be more consistent to leave with the suspension loaded.
Posted By: Cappy572

Re: Cutting lights - 02/26/12 11:50 PM

All good advice on changing the car. Dont forget car placement in the beams is equally important for consistant reaction times and consistant ET. Make sure you barely turn on the second stage bulb to indenty you are on the same mark every time. This can be a differance of 2 hundreds on the starting line and the finish line. Stage deeper in the second bulb you will go 2 hundreds quicker on the tree and run 2 slower down track.
Posted By: PolyDart

Re: Cutting lights - 02/26/12 11:51 PM

Quote:


If you are going red leaving the line at a dead idle you are anticipating the 3rd light coming on.



Not the case. Since leaving off the yellow was too slow, I would pause and try to hit it half way between yellow and green. Since there was nothing to consistently react to, I was all over the place.
Posted By: dmking

Re: Cutting lights - 02/27/12 12:00 AM

i have the same issue. when i leave like my bike i -.00x the car. i went up to 26"tall tires from 25". that should put me in the ball park. but i have proparts headers and can get away with taller tires better.
i will find out this season.
Posted By: moparacer

Re: Cutting lights - 02/27/12 12:02 AM

Quote:

Since leaving off the yellow was too slow, I would pause and try to hit it half way between yellow and green.



I think you are mixed up here a little.

If you were slow leaving off the yellow, waiting to leave between the yellow and green would make you even slower.....

I dont know...Anyways look at this video me me in my old car footbraking with a setup similar to yours.

http://youtu.be/BaAvUO4LRPs

I am leaving at 2000 RPM and leaving when the 3rd light comes ON.

This wasnt a killer RT I think around .030 or so but this is how I have done it, and won a lot of races over the last 23 years.


Posted By: VernMotor

Re: Cutting lights - 02/27/12 12:02 AM

yes I would try to leave off the last yellow with some RPMs first. see where that gets you. changes to the car tire pressure.. rear and front. T-bar adjustments. you may even need to send the converter in and have the stall speed change..there is more but depends on what suspension you have ? leafs-ladder bars-4-link .. and shocks play a big part in this.. Lets face it.. no matter how fast how cool you look..if you can not cut a light you will never go rounds..I do what ever it takes on a given day to make that happen. and yes make sure you stage light and same way every time.. this is very very importance.
Posted By: aquamist60

Re: Cutting lights - 02/27/12 12:02 AM

You can try adjusting your front tire pressure, too slow-increase pressure, too quick-let air out. But I do agree you have to be right first before you can get the car right. Try staging, adjusting launch rpm, make sure your carb is reactng properly run after run, proper pressure rea tires, shocks set correct. A lot more, this just starting point.
Posted By: JD Dart

Re: Cutting lights - 02/27/12 12:08 AM

If your distributor isn't locked out change the curve on it like all in at 4800 or what ever max curve you can get out of it. Also have the centrifugal advance timing set to the max. Like with the MSD you can have it setup for 28 degrees so if you wanted 36 total you would set base timing at 8 it will run bad and very sluggish when you tip into the throttle. At that setting you may have to leave on the second yellow.
Posted By: PolyDart

Re: Cutting lights - 02/27/12 12:12 AM

Quote:

I think you are mixed up here a little.

If you were slow leaving off the yellow, waiting to leave between the yellow and green would make you even slower.....



Yeah, I wrote that wrong. Leaving when I see the yellow leads to a red light, which is why I paused and hit it between yellow and green. Sorry for the confusion.
Posted By: Crizila

Re: Cutting lights - 02/27/12 12:13 AM

Quote:

Quote:

Ok, let's say I want to leave on the last yellow. Other than a delay box, how would I slow down the car's reaction?

I did read where one of you said staging RPMS, but leaving off idle should give the slowest reaction since the engine has to come up on power, the suspension has to load, etc... I may be mistaken, but I would think I am already setting the car on the slow end of reaction.



If you are going red leaving the line at a dead idle you are anticipating the 3rd light coming on.

Yep - almost for sure on that. This was something I had a problem with ( especially running slower cars ). You have to discipline yourself to make sure you see the light come on before you mash on it. As said, a practice tree will help, but the best thing is just time in the seat and sticking to a routine. My routine starts once I am positioned in the water box. If I have to shut down after that due to track conditions, I always back all the way out of the box and start over again - no matter what my apponent does. I also always look at his dial to make sure I know who is going to be leaving first.
Posted By: moparacer

Re: Cutting lights - 02/27/12 12:19 AM

Quote:

Yep - almost for sure on that. This was something I had a problem with ( especially running slower cars ). You have to discipline yourself to make sure you see the light come on before you mash on it.



Yep a lot of guys dont realize that the fact that you know the tree is dropping can make you 3 or more hundredths quicker. You are mentally anticipating it.

Just hold your hand up and block the first two once. Then you will see just how much slower it makes you.



Also, get someone to video you at the track like I posted up above.

You will be able to tell exactly where you are leaving at and can adjust accordingly.
Posted By: 383man

Re: Cutting lights - 02/27/12 12:32 AM

I found I had to adjust my leaving with my new 493 I put in last summer compared to my old 440. I come up on the converter between 2000 and 2500 and the instant I see yellow on the third bulb I go. At my local track I usually cut .010 to .050 all the time as long as I stage the same way which is shallow staging for me. I usually dont run a Pro tree so I dont have to worry about deep staging. Now when I went to another track last summer I kept redlighting so I had to adjust and I just try counting. When the first yellow comes on I count the yellows as they come on as in.......1 , 2 , 3 as the last yellow comes on and normally I am leaving at 3 but at this other track I put 4 in there and left on the 4 count in my head so I would not red lite. It seems to work ok for me. Course I like my local track best as it is easiest to leave on the last yellow coming on which is the 3 count for me. Ron
Posted By: 383man

Re: Cutting lights - 02/27/12 12:35 AM

This was 2 years ago with my old 440 using my method. I ran the 11.49 and I was pleased with the lite as I dont race alot. Ron

Posted By: 383man

Re: Cutting lights - 02/27/12 12:38 AM

This was this past summer with my new eng. I had to adjust a tad as the car leaves harder now and this was my average lite that day adjusting with my count method. Sometimes I even adjust on the number 4 if I have to as if its a tad slow I will leave just as I start to think the number 4 before I actually say it in my head. It just gives me a more consistent way to cut lites. Ron

Posted By: Cab_Burge

Re: Cutting lights - 02/27/12 01:31 AM

I normally wouldn't comment on this but who says I'm smart Several things already said is what I preach to those that want help, ALWAYS adjust the car, not the driver 2nd thing is adjusting the car, to slow down your reaction times try stiffening up the front shocks,limit the front end travel where the car has to pick the front end up sooner, try higher stall speeds, change squirters, the old M.W. SS racers use to use way to big squirters to load the motor up so it wouldn't spin the tires on the line, they where very lazy back then, new converters may nullify trrying that now Less air in the front tires, more or less air in the rear tires. Make your self a tree blind so you can't see the first two yellows, lots of ways to adjust I use to be able to cut .501 to .520 all day long, until first or last rounds and then they became .499 or worst it use to be esy to win when I was younger, 25 yrs ago It's a lot harder now Have you had the front end alignment set to get some stagger on the front tires YET NHRA allows one inch stagger on the wheelbase between the two sides of the car Lots of ways to affect the car Theres a lot of difference between anticipating and reacting
Posted By: Leigh

Re: Cutting lights - 02/27/12 02:43 AM

Quote:



Just hold your hand up and block the first two once. Then you will see just how much slower it makes you.




+1 This will help identify a DRT or VRT issue. I personally would go .490, .495 red. The converter, carb, cam, rollout, chassis setup is key.
Posted By: pittsburghracer

Re: Cutting lights - 02/27/12 03:26 AM

Thirty + years ago I had to do exactly what Cab touched on (tree blinder). My duster was running 9.80-10.00 quarter mile times on super stock springs and even staging at 1200 rpm I would redlight on the last yellow so I put a visor on my helmet and I put about 4-5 pieces of black electrical tape across the top of the visor. I could lower my head in the car and BLIND out the other yellow bulbs. As soon as the last yellow came on I was gone. It takes out the anticipation and makes it more like a pro tree. Worked for me.
Posted By: Just-a-dart

Re: Cutting lights - 02/27/12 06:08 AM

Quote:

The short front tire isn't ideal, but you should be able to make it work. The biggest issue is you. Go buy a practice tree and use it, you will improve.



But you have to adjust the roll out time to match your car's reaction.
Posted By: Jeepmon

Re: Cutting lights - 02/27/12 06:16 AM

If you're coordinated enough to release a button and move your foot at the same time.. Put an adjustable switch on your line lock and launch using both..
Posted By: FlyFish

Re: Cutting lights - 02/27/12 01:49 PM

Quote:

Thirty + years ago I had to do exactly what Cab touched on (tree blinder). My duster was running 9.80-10.00 quarter mile times on super stock springs and even staging at 1200 rpm I would redlight on the last yellow so I put a visor on my helmet and I put about 4-5 pieces of black electrical tape across the top of the visor. I could lower my head in the car and BLIND out the other yellow bulbs. As soon as the last yellow came on I was gone. It takes out the anticipation and makes it more like a pro tree. Worked for me.



Make a visor and block out the top 2 bulbs...that way you will find out if you are anticipating the light because you will be reacting to the bottom bulb. I did this a few years ago for the same reason and found that I was anticipating the bottom bulb. My lights were too slow using the visor method, but it helped me with my current way of leaving the line. It might sound funny, but I literally say out loud in the car as I roll into the last stage beam "SEE IT!". This reminder helps me to wait till I see the bulb so I react to it, instead of anticipating it.
Posted By: StealthWedge67

Re: Cutting lights - 02/28/12 07:56 PM

Quote:

I would redlight on the last yellow so I put a visor on my helmet and I put about 4-5 pieces of black electrical tape across the top of the visor. I could lower my head in the car and BLIND out the other yellow bulbs. As soon as the last yellow came on I was gone. It takes out the anticipation and makes it more like a pro tree. Worked for me.



+1.... I don't race as much as most of you guys, but I was having the same issue, did exactly as described above (black electrical tape across the visor on my helmet), and that very day, had my best day ever, winning (4) rounds and losing to a really tight package in the 5th. I'm sure it feels as though you're leaving on the yellow, but chances are good that you are actually anticipating the last yellow. Not only did this help my red-light issue, but I was suddenly real consistant. Not as quick as I wanted, but consistant; and that's a place you can start adjusting the car from.
Posted By: FurryStump

Re: Cutting lights - 02/29/12 03:45 AM

It's very important to have a consistant starting point. I just inch in VERY SLOWLY until I turn on the second beam, I run a pro tree so I leave when I see the faintest hint of amber. I average .01 to .02 lights not great but good. If i want to really cut a light a bump the car one bump extra into the lights. If I'm going JUST barely red consistently I can take air out of the front tire or Change which light I'm looking at, on a pro tree the top amber comes on earlier than the second an so forth, If I'm really close but still red I'll watch the bottom amber instead of the top.
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