Box Stock

Gearing one more time

bullerman said:
Got the shoes turned with the L facing forward. Shoes and drum clean. Hope this does it. I was looking at the BMI gear chart. For the gear I was running 15/64 with a right rear tire diameter of 11.5 inches, the left is a little smaller turning 4500 rpm speed comes out to 36.8. I was at a little over 35 mph.
Racing promoter suggested a 16/60. I tried it but just didn't think i was turning enough rpm but I had the fastest lap I have run with that gear. Mph wise all I would have to turn is 4100 in theory to be two miles an hour faster. I just don't think the track is large enough or I have guts enough to get 4800 or 4900 rpm out of the motor. I probably am going back to the 16/60 . Thanks for all the suggestions.
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Forget about gearing for now, don't even take different gear options along to the track lol
Focus on yourself making momentum and maximizing it more, then tires, tires , tires,tires, did I say tires, your not making enough forward drive, of course air pressures go hand in hand with tires, do that until you see rpm gains the more rpm gain you see the closer you are, then once you see substantial gain and it stabilizes then tweak gearing, and maybe set up based on handling.
NOTE the only way this doesn't workout is IF your gearbound now significantly, I don't think that's the case but throwing it out there.
 
Like I posted. We run grooved tires with no prep. 1 3/4" front 1 1/4" rear stagger. At the moment I don't have a choice.
I do think there is some driver error. I was looking at real time lap speed. I can see that on some laps I am letting off to soon going into the turns so I a. Definitely loosing some speed. I need to carry it deeper if I can. Sometime my rpm drop might be 800 some time 1600 so I am not consistent.
When they start getting grooves back in I am going to buy a new set. I am running two tx11 and two tx22. They are too soft for this track. I will probably go with 33's. It sounds like i am on pavement in the turns. Hey I am having fun though!!! Never thought I would be 75 and still racing.
 
Last race ran a 14/60and was a little over 4800 rpm. Looks like that is what it is going to take to get in the 4800 to 4900 rpm range. Now should I run the 14/60 or 15/64. Both are about the same gear ratio. I believe my high speed was right at 36mph. I am running grooves. Right rear measures 371/2" roll out. Thanks for suggestions.
 
bullerman said:
Last race ran a 14/60and was a little over 4800 rpm. Looks like that is what it is going to take to get in the 4800 to 4900 rpm range. Now should I run the 14/60 or 15/64. Both are about the same gear ratio. I believe my high speed was right at 36mph. I am running grooves. Right rear measures 371/2" roll out. Thanks for suggestions.
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If your convenience you've figured out the ratio, neither one you mention try 13/56
 
I didn't mention a 13-56. At the moment I don't have a 13. I have tried 14,15 and 16 drivers with different rear gears. The 14-60 put me between 4800 and 4900 rpm which is where I thought I should race. Was just wondering if I would be better off with the larger driver if the motor could pull it easier.
 
bullerman said:
I didn't mention a 13-56. At the moment I don't have a 13. I have tried 14,15 and 16 drivers with different rear gears. The 14-60 put me between 4800 and 4900 rpm which is where I thought I should race. Was just wondering if I would be better off with the larger driver if the motor could pull it easier.
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NO , I know you didn't mention it , I know where your at and yes that's where ya wanta be, and I'm telling you what you wanta do next buy a 13 driver and try a 56.
Good luck !!
 
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