logic factory

anyone have any quantifiable results of how advantageous gearing can be in drag racing. i.e. the only variable changed between passes was gearing; whether with tires, transmissions, differentials.

here are my only results:
i went from a 225/45/17 to a 225/50/15 and the car picked up ~1.5mph in trap speed. the above change in tires is similar to changing my differential from 3.23 to 3.38 while maintaining same tires and transmission.

does anyone have any results with a larger change in gearing and if so what were they?

here is the online calculator i use to for gearing
http://www.f-body.org/gears/

SS4Luck

iTrader: (10)

I dropped .3-.5 in the 1.8th mile going from 3.42s to 4.11s.

im now going to 4.56s though

this was before my cam when car was just full bolton with nittos

joblo1978

iTrader: (14)

Am I reading this correctly? You dropped half a second in the 8th mile from just a gear change?

I'm currently waiting for my S60 to ship with 4.10's, and that is some serious good news to me.

BlackScreaminMachine

iTrader: (17)

Well what you will be looking for is the concept called.

Torque Multiplication.

For your post in particular, the gear definitly increased but What I wager also happened was the difference in Rim Size.

What was the 17" Rim (WS.6, SS etc etc) and when going to the 15" which one did you choose. As simply the rotating mass had a large factor.

What tire did you use on both, compound etc etc.

What was the 60 foot diff. Or simply list BOTH timeslips.

WS6TransAm01

iTrader: (13)

I went from a 11.85 to a 11.30 years and years ago when I switched from 3.73's to 4.11's Also went from a 1.72' 60' to a 1.52'

Now I have 4.56's with 28" tires and I wish I could fit a 30" under there so I can run 4.88's or 5.00's lol

SS4Luck

iTrader: (10)

with the stock gear nd exhaust/tune w/ nitto DRs i was running 8.5X consistantly in the 1/8th mile. I went to 4.10s and immediatly started runing 8.3-8.2 and by the time my motor let go nefore i put my cam in my best time was 7.99 with an average of high 8.0X the only changes to the car were gears, shift **** and headlights. So yes i believe my 4.10s netted me .5 in the 1/8th. I will also say though i think i learned to drive my car a bit better in the process which helped with the drop in time.

logic factory

black
im familiar with how torque is multiplied by gearing but i wanted to see real world results that more people would be interested in.
using my car as an example the smaller tires resulted in ~139 extra torque in first gear, 83 2nd, 55 3rd and 40 4th. than things get more dynamic because for those numbers to have more significance one would try and isolate how much time was spent in each gear. i suspect the results would be around a 60ft lbs extra torque when considering as many variable as i can wrap my head around at this time. so a guessed average over the course of the track of 60 ft lbs extra torque netted about 1.5mph. now thing get more dynamic because my wheels were a little lighter(about 2lbs a wheel[rim and tire]) only for rear. now one needs to consider where the extra weight was added to the rotational mass to better understand the impact it had on the results. being the outside of the rotating mass i understand it helped me more than if it was at the wheel hub. these are a bunch of useless numbers and steps most people dont care about, so i was tring to get more pure results, understanding mine were tainted. my point is, i understand(to a degree) how convoluted the example i supplied was but i was trying to give people an idea of the information i was looking for. allowing others to make a better correlation between gears are worth about this much time and this much trap speed.

trans
do you recall the improvement in mph?

luck
can you share how many mph you gained with the 4.10's over stock gears?

i will share better information when i have it as i plan to switch just gears and keep same wheel setup. this may not happen this year but when it does ill share my results. thanks for the replies thus far.

BlackScreaminMachine

iTrader: (17)

What you need is a car with an automatic and a 9" rear for quick gear swaps at the track and then you can see the real world difference for gearing. The only variable for the most part will be Density Alt. A track rental day with 30-50 cars, just enough to make sure there is heat in the track and you can go all day long.

THEN throw in a varible of different power adder type cars, or N/A set ups and see how each react differently.

With the fact that your examples have TOO many varibles to fit into your model you have to find cars that change one and ONLY one thing and make sure the conditions are similar and then you can take data as viable information.

logic factory

i agree^