Car is lower 7 sec in 1/8 mile. Pinched nerve in spine (left leg) limits ability to hold high launch rpm when footbraking. With a 1.55 60' how much reduction in reaction time can be expected going deep? Trying to be competitive at some of the high end footbrake races

Don't know how you like to "leave" ....... but, if I had a car like that (with the numbers you provided) ...... I'd deepstage ... torque it to 2200 to 2400 rpm's ... block the first two ambers ..... and go kick azz! ....

Dave

quote:

Originally posted by muggs:
Car is lower 7 sec in 1/8 mile. Pinched nerve in spine (left leg) limits ability to hold high launch rpm when footbraking. With a 1.55 60' how much reduction in reaction time can be expected going deep? Trying to be competitive at some of the high end footbrake races

You didn't say what kind of lights you are getting at high/low rpm.

If I had to guess,I would say you would probably redlight by going in deep.

That is a good thing.Then you need to see how much you are red and adjust from there.

I usually run No-Box. Have not footbraked steady since before 2010. Had nerve fixed in right leg in 2015. Now getting same issue in left. Car leaves hard off third bulb and tree usually competitive. Been trying to leave shallow footbrake but very erratic due to serious spasms in leg trying to hold 2500+ at line. Will try deep next race/TT and see how car performs.

Appreciate the input gentleman.

I don't know exactly what we loose 60'because we deep all the time, and its been years since we hit the shallow bulb.
Our car is very slow getting out of the beems. We 60' 1.71s deep, but runs 7.50s at 94mph. From what I remember the last time we tried shallow we were about .080 slower on the tree and about .010 quicker in the 1/8.


I sent ya a PM

quote:

Originally posted by Steve from Pa:
I don't know exactly what we loose 60'because we deep all the time, and its been years since we hit the shallow bulb.
Our car is very slow getting out of the beems. We 60' 1.71s deep, but runs 7.50s at 94mph. From what I remember the last time we tried shallow we were about .080 slower on the tree and about .010 quicker in the 1/8.




I sent ya a PM

I would certainly think that your car would pick up more than .01 at the 1/8 mile on a shallow stage vs a deep stage.

Whatever you pick up in R/T going shallow to deep or vice versa, you pick up the same exact amount in the 1/8 and 1/4.

quote:

Originally posted by Mike Beck:
Whatever you pick up in R/T going shallow to deep or vice versa, you pick up lose the same exact amount in the 1/8 and 1/4.

Fixed for you.

quote:

Originally posted by Lenny5160:

quote:

Originally posted by Mike Beck:
Whatever you pick up in R/T going shallow to deep or vice versa, you pick up lose the same exact amount in the 1/8 and 1/4.

Fixed for you.

Yeah, that's what I meant to type...

You gain on one end and lose it on the other.

Using the same RPM's that you launch with shallow staging, you'll likely see around .07 gain in RT and .10 loss in ET. Unless your 'spot' is .060-.080 average on RT when you're shallow, you'll probably go red (assuming it's not worse than that range). For every .01 that you go red at the same RPM, back off 100 RPM and it should equal .01 in RT per 100 RPM. While backing down on launch RPM's, you might see a few thou per 100 RPM less launch, in ET loss.

You guys are correct - sorry - decimal in the place .10 not .010.

We only tried it once a couple years ago. We saw .080 on the RT, but from what I remember we picked up a full .10 at the time, but we also raised out staging RPMs about 200 or 300 because we didn't think going shallow would get us were we wanted, so yes probably 070 and that down track would be very accurate.

About 10 numbers will be very close. Good Luck!!

I normally shallow stage but before I changed rear gear I had to do it. Pulled log book to check. Shallow I was .07-.08 and deep I was .002 and .009 the next 2 hits. 60' went from 1.55and 1.57 to 1.65 1.66

I tried deep, car was super red. I am going to skip trying foot races until I can get surgery to fix the nerve. I can still run no-box and box.

Thanks for all the input guys.

I had leg problems and had to modify my brake pedal to "feel" it better to footbrake. I was going to put a brake pressure gauge in the car or a brake pressure switch with a light on the dash so I knew I had enough pressure.