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Old 08-30-2021, 12:31 PM
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Default footbrake help

I need to do something different or practice more as yesterday I only won one round. Sucks we only get one time trial on Sundays.

I use the stage rpm to adjust reaction times, around 2000 rpm. GTO 60 foots 1.64

If I bring up the rpm after I stage, sometimes there is not enough time to look down at the tach and back up before the lights start. Tach is mounted on the steering column ( street car ). I have tried to go by sound to gauge rpm and I do get close.

I just turned all four brake drums and put on new pads, Yesterday I tried bringing the rpms up after pre-stage and move to the stage light, but the car seems to lunge forward. That is probably why I red light yesterday, too far into the stage light.

I thought about a light for stage rpm. Anyone use these?

https://www.raptorperformance.com/co...t-launch-light

or a dual stage tach/light, not sure what the model number is

https://www.autometer.com/pub/media/.../2650-1244.pdf

Any other ideas?

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Old 08-30-2021, 04:32 PM
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That stage light is an interesting idea, I haven't seen one of those before but it makes sense.

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Old 08-30-2021, 07:24 PM
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Not sure what ignition you have but you can also program a MSD 2-step ignition off the brake light switch to a specified RPM.

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Old 08-30-2021, 09:05 PM
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I race in a class where:

Delay boxes, Tran’s brakes, throttle stops, stutter boxes, and automated shifters prohibited. Two wheel line lock only permitted. Two-step rev limiter PROHIBITED. No three or four step allowed.

So, no starting line rev limiter or fast idle carb/throttle switch, like used on a/c cars, is allowed.

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Old 08-30-2021, 09:27 PM
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You can have 1 rev limiter? red line limiter?
A few of the street ET guys tried like Johnny406 said except they used the red line limiter at 2500 or whatever starting RPM wanted connected to the brake switch.

Not sure if still legal or not, was 20 years ago.


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Old 08-30-2021, 10:24 PM
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A rev limiter can be used when the car is in motion. No electronics during staging. Throttle has to be operated by your foot, no device can affect throttle operation or rpm. I'm not sure a rpm light can be used during staging, but I'd like to try that if no one has any tips for how to footbrake constantly with drum brakes.

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Old 08-30-2021, 11:01 PM
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Id look into why the car lunges forward when trying to stage it 2000rpm.
Our technique for all our cars when foot braking is, prestage, bring to rpm, then creep in until stage bulb is just lit. We've never had an issue creeping in at rpm (we stage anywhere from 1600 to 2400 depending on the car)

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Old 08-31-2021, 07:30 AM
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I used to do the same as slowbird, pretty consistent 9.60's once all the fluid temps had stabilised, 1.34 60fts.

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Old 08-31-2021, 09:00 AM
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and for the snaeky bstard....you take the rpm activated switch and use it to POWER your tach....so your tach is DEAD ....UNTIL you reach your set point ...no lights...but you can surely see WHEN the tach needle JUMPS...."must be at or above my set mark:.

The 2 step light is great since you can't have a rev limiter.

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Old 08-31-2021, 10:04 AM
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Quote:
Originally Posted by tc View Post

I just turned all four brake drums and put on new pads, Yesterday I tried bringing the rpms up after pre-stage and move to the stage light, but the car seems to lunge forward. That is probably why I red light yesterday, too far into the stage light.
I would call that 'lunge' normal, with fresh turned drums and new shoes.

Pedal effort, for easy creep, will change when drums and shoes get broke in.

Clay

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Old 08-31-2021, 10:15 AM
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OK, I was thinking that maybe disc brakes were needed to creep up to the stage light.

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Old 08-31-2021, 11:00 AM
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Quote:
Originally Posted by "QUICK-SILVER" View Post
I would call that 'lunge' normal, with fresh turned drums and new shoes.

Pedal effort, for easy creep, will change when drums and shoes get broke in.

Clay
If you can find a older brake shop they can turn your shoes to match the drums

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Old 08-31-2021, 11:34 AM
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most just "adjust" the arc with a 2x4 and hammer.....doubt there is still somebody ALIVE that would even know how to cut a set of shoes..

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Old 08-31-2021, 12:17 PM
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A place in Findlay still does them that’s why finding a older shop was said and yes they are alive.

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Old 08-31-2021, 12:22 PM
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Never heard of that, but just watched a youtube video of a guy using a brake shoe arc grinder.

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Old 08-31-2021, 12:59 PM
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It’s so shoes are matched to drum from the start not just on the ends.

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Old 08-31-2021, 08:12 PM
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I use four wheel drums and foot brake. I pre-stage, bring it up to 2500 rpm and bump the brake to stage without lunging.

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Old 08-31-2021, 08:13 PM
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Get an RPM switch with pills. Have the RPM switch light a shift light.

The only issue is if you are higher than the pill you won't know it.

OR, leave off idle and adjust where you mash the pedal.

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Old 08-31-2021, 08:44 PM
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Hi TC – where are you racing?

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Old 09-01-2021, 03:08 AM
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What kind of converter are you runing ?

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