Posted By: 1976 Aspen
Questions on throttle stop racing... - 01/06/11 05:59 PM
I'm plan on racing in the electronics class this year and have no idea what to expect. I have a 1976 Aspen that runs 10.0's right now and I want to race the 10.90 index. I'm using a PPP air shifter, Dedenbaer Command Center 3, and a blade style air throttle stop made by #1 Stop. I'm going to shift it at 7000 rpm's via RPM on the CC3 and not over time. I was wondering if I could throttle stop it in 3rd gear instead of first gear??? What are the pros and cons of throttle stopping in first gear rather than second or third. Sorry for the silly questions as I'm an electronics virgin
Posted By: MR_P_BODY
Re: Questions on throttle stop racing... - 01/06/11 06:25 PM
Its easier to accelerate using the lower gears VS
high gear to give you the MPH (which most throttle
stop cars run)
Posted By: Anonymous
Re: Questions on throttle stop racing... - 01/06/11 07:47 PM
More outside forces can effect the car when it is coasting in high gear like headwind, friction of the track, aerodynamics of the car.
Posted By: MegaDart
Re: Questions on throttle stop racing... - 01/06/11 08:06 PM
a tach wire connected to delay box is not allowed in super classes. Most guys I know shift on time partly for that reason. Most shift almost immediately after going on the stop. Your results may vary and of course my experience is with a 2speed not a 3speed
You have all the right equipment to get it done!
Posted By: AAR-B4
Re: Questions on throttle stop racing... - 01/06/11 10:14 PM
Here's information from the best in the business.
http://www.biondoracing.com/tips.shtml#throttle
Posted By: Eric
Re: Questions on throttle stop racing... - 01/06/11 11:01 PM
I have a friend who was pretty successful using a stop just before 3rd gear shift....really screwed with the competition too.
Posted By: bcrproducts
Re: Questions on throttle stop racing... - 01/07/11 12:14 AM
Totally agree with this statement. Unless you run a dragster this is not a good idea. All of the very succesful stop racers do it off the launch.
I raced S/G and S/St for years and I played with all of the various ways of stopping a racecar.It is nice to have an override but at 10.00's you likely don't have enough oomph to play that game very well. I liked to be able to pick up about3/10 if needed on the override. Not that you would ever use 3/10 on the override.
MPH is the key. When I used to race Jeff Jackson's Rug Docter S/St Mustang he would go as high as 160 MPH at 10.90.That was I beleive a 900HPmotor in that monster and quiet as a mouse. The speed differential is enormous and very hard to guess. I was running about 147mph at 10.90 and at that time was one of the quickest 10.90 cars besides Jackson. You want MPH if you want to be truly succesful in super classes. All the best guys have MPH-Jackson,-Ferd, Henderson to name a few in div 6.
Greg
quote]More outside forces can effect the car when it is coasting in high gear like headwind, friction of the track, aerodynamics of the car.
Posted By: CMcAllister
Re: Questions on throttle stop racing... - 01/07/11 02:39 AM
It is much easier, for many reasons, to make the car competitive when using the stop early. Useful throttle stop ratios, predictability, consistency, having the RPM curve remain flat on the stop and finish line MPH, are just a few of the considerations.
You have a few options. You could shift 1-2 very early on time and run the stop like the higher horsepower, 2 speed racers do (stop on, shift, stop off). The timing of these 3 events is the trick, but by running it like a 2 speed, with some adjustments, it should work fine.
You could also shift the car by time or RPM a little farther out, maybe 60' or so, and then run the stop in second gear. Probably best if the car doesn't have to be slowed down quite as much.
In either case, manually shifting high gear by RPM would likely be easiest if you are shifting 1-2 by time. Running the car like a 2 speed car for the first 2 gears will be the easiest to get a data base to work with. Typically the stop is on before .5-.7 out, much earlier with the big horsepower cars. Running it like a 2 speed, instead of trying to reinvent the wheel, will let you to run the car like most folks do and allow all of the advice available to be used.
Expect to test and try different things before finding the sweet spot. Many factors of your car's combination will determine what it likes best. Figuring all of this out and learning how to run the index consistently, is more fun than changing the number on the window.
Posted By: 1976 Aspen
Re: Questions on throttle stop racing... - 01/07/11 03:35 AM
Thanks for all the tips and tricks guys!!! I guess it will be quite a learning curve and maybe a little frustrating at the same time. My car will probably only be going around 135 mph so who knows what will happen...
Posted By: CMcAllister
Re: Questions on throttle stop racing... - 01/07/11 04:12 AM
It is quite a learning curve, especially with an odd combination like yours. Expect to have to work at it. .90 racing is a lot of fun. Just expect to hear a lot of s*&# about it being boring, not real racing, ruining the sport and all the rest of it. The good racers make it look easy until you jump in.
Posted By: Al_Alguire
Re: Questions on throttle stop racing... - 01/07/11 05:31 AM
Well not sure how much help it is but here goes. get the car on the stop as soon as you can and into high gear as soon as you can. Those two things should give you the consistency needed to be competitve in the sport. Now we can talk all night about finish line strategy, how much to hold, if to hold, blah blah blah.
FWIW I go 155ish on the stop at 10.90. Been 159+ but just cant seem to make that work consistently. My first number in the stop is .000, I shift at .50-.75 looking for my ideal 60' at each given track. I am off the stop in the 4.6-4-8 range depending on the weather and track conditions.
Posted By: Eric
Re: Questions on throttle stop racing... - 01/07/11 03:33 PM
I would have the stop come on .300 out...try setting at 3800-4200 rpm...I'm thinking in decent air you will carry 1.5 in the stop..
Posted By: bcrproducts
Re: Questions on throttle stop racing... - 01/07/11 05:09 PM
I used to run 000 in the stop as well. You want to run as little as possible and yet still be able to cut a light.
Greg
Posted By: rickstershemi
Re: Questions on throttle stop racing... - 01/07/11 07:18 PM
I'm thinking leaving @ 4500 on the stop .150 out @ 5500 - 6000 and shift 2nd (on time) before coming off the stop, then adjust your on-stop time to for 10.90....just-a-thought
If that gets you there then try it on the stop for .5 second and then 2.5 to find your t-stop ratio
Rickster
Posted By: Al_Alguire
Re: Questions on throttle stop racing... - 01/08/11 03:23 AM
IMO the big issue is going to be the second shift from 2-3. From what I have seen with folks I have helped and talked with getting it in high gear as soon as possible is gonna be the key to consistency. You will HAVE to shift on time. IMO with a TF 1-2 should be really quick, like .5 or so but on the stop for sure. I think you will be looking at 1.8-2.0 seconds on the stop IF the car indeed can run 10.0 all out. iwoudl think shifting to high just after coming off the stop will get you what you want. Converter selection will be a big deal as well. just my
Posted By: Al_Alguire
Re: Questions on throttle stop racing... - 01/08/11 04:38 AM
May be but you have to admit you are charging the top end a little quicker that he will be doing. Only way to know is plug in some numbers and find out. he stated he can go 135mph which is more MPH that is needed to go 10.0. I am just guessing it is geared more for MPH, but might be wrong.
yo are probably correct that it will be less. He has to kill .90, or whatever he wants for the strategy he desires at the stripe. We all know bets way is to establish a ratio and do the math from there.