higher staging rpm stall speed= reduction in R/T
 

Hey guys a read a great article in the National Dragster Jul 23 2010 issue concerning reaction time..It is on page 52 and was written by Luke Bogacki..

I was wondering if anyone knew why:

If I put my stagaing speed up to say 2000 rpm&shallow stage, I can leave onthe 3rd yellow and cut a decent light. This is opposed to deep staging and staging at 1000 rpm and then leaving on the 3rd yellow..

Re: higher staging rpm stall speed= reduction in R/T
 

If you "crowd" the converter too much, ie get to the point the car starts to creep, you are taking away the flash. Just because you can foor brake your car to 2500 doesn't mean you launch it there. You need to be about 400 rpm lower than the point you can still hold the car. This will let the converter flash, and the engine will make rpm quicker thus moving your car quicker. IT is different for every combination though, so you have to see where your car works best. You can also raise the air pressure in your front tires to help reaction times.

Re: higher staging rpm stall speed= reduction in R/T
 

Maybe you should just shallow stage and try the different launch RPMs. If that thing 60 foots better than a 2.0 you shouldn't need to go deep.

Re: higher staging rpm stall speed= reduction in R/T
 

I found that when I stalled at 2000 I could still hold the car, this was with a old and likely "not functioning very well " convertor..I have since replaced it with a Hughes Pro-Stree unit that stalls at approx 3000..it will be interesting to see how the car reacts. It is a heavy car 3900 lbs 468 BBC .231@50 cam..

So, I guess that the theory is if you are footbraking at 2000 and the convertor is 3000 than it takes "less time" to go from 2000-3000 than 1000-3000?

I am running front runners with 165-70-15 radials@40 psi.

Re: higher staging rpm stall speed= reduction in R/T
 

I was chatting with someone at the ATI trailer about converters a couple of years ago. I asked about staging RPM's having any effect on the performance of a superstock combo. If I understood him correctly he stated that if a converter was set to flash 5200 with your combination it will do it if you stage at 2500 or 4500. This did not take into account an issue with a carb that that has not had the accelerator pump set up properly and stumbles when you nail it at low RPM. He also said many times a car will be quicker if you "hit" the converter from a low RPM vs max stall, but different stage RPM's will alter your reaction times. Don Jackson

Re: higher staging rpm stall speed= reduction in R/T
 

I 60 foot 1.39-1.41 shallow staged, and can't be better than .035 on the tree.

Re: higher staging rpm stall speed= reduction in R/T
 

[QUOTE=bottombulb;207427]I 60 foot 1.39-1.41 shallow staged, and can't be better than .035 on the tree.[/QUOTe

XX

Re: higher staging rpm stall speed= reduction in R/T
 

Have you checked your pulse lately?Just kidding.
I go 1.77-1.79 @ 60'.6cylinder 3040 # and have no trouble .010-.030,if my mind is there.And i'm 65 years old.

Re: higher staging rpm stall speed= reduction in R/T
 

I leave at <1500 rpms or I'll go red ;)

Re: higher staging rpm stall speed= reduction in R/T
 

Me too!!!! (deep though);)

Re: higher staging rpm stall speed= reduction in R/T
 

Hey Bob, I don't know about all that wasted motion happening...:D

The car 60ft's in the 1.6 region, I finally got it back on the road last night, hopefully race Sat or Sun..



Kris

Re: higher staging rpm stall speed= reduction in R/T
 

I leave at 4000 on mine and have the best R/T at that..........

Re: higher staging rpm stall speed= reduction in R/T
 

Stall speed will change your R/Ts but every car is different, my bracket car changes about .010 for every 200 rpm change. There are some different ways to change your R/Ts if the stall speed dont work for you or your car. You can adjust front and rear tire pressures or adjust the travel in your front end, if you tighten your front up it will make your R/Ts quicker but you will be more likely to have traction problems. Its all in finding what works for you and your car.

Re: higher staging rpm stall speed= reduction in R/T
 

1100 # of brake pressure, 3400 in the stutter box, gas pedal on the floor, will go.020 to red. short time is 1.48 to 1.55 with a old old 4500 rpm 8" A-1 torque converter and a 2.78 low gear C-4, 5.14 gear and 29X9 Hoosier's car weighs 3520 with me in it.

Re: higher staging rpm stall speed= reduction in R/T
 

Good luck at the track :thumbsup: :D

Re: higher staging rpm stall speed= reduction in R/T
 

i have tried with the two step and just foot break and two step off the brake with the box set at 3200,now turn it up and you use more brake presure and it turns into an elastic band ,the converter will not act the same ,you lose the flash of the converter ,you have to wait and see alot of yellow to be green,,but foot braking you almost have to leave at the hint of yellow to cut a .030 light, i have data logger and the two step is real consisntant on rpm to where the gas and go has a real jagged line and the converter hits way different between the to approches ,,,if you have a real tight converter you will not have a choice the foot brake ,you cant two step the motor to low or it will pop thru the intake ,,,,,if you run a holley foot braking is the way to go you can tune those to any weather condition but stocker carbs can be tempermental gmonde

Re: higher staging rpm stall speed= reduction in R/T
 

Hey guys,
This weekend I had a chance to try it out again..I found as stated by gmonde that when you shallow and stage at a higher rpm you need to leave at a hint of yellow to cut a good light. I cut a .560 (we use a sportsman tree) but broke out anyways....You have to have a aggressive mentality when your doing this. For those who played football it is like you are on the defensive line watching the center snap the the ball and exploding onto the o-line..

Kris