gearing for 1/10 clay oval

yeah I figured that was a heck of a handicap so I was trying to make up for that in gearing, well at first we ran 13/65 and had 5170 rpms, then we went to 12/60 and got 5170 rpms, then to a 12/62 and got 5250 rpms, then to a 12/63 and turned 5500 rpms now we are at the 12/64 and got the 5630 rpms and with all this he still runs 3 or 4 th. been experimenting with tire pressure also run 4 1/2 pnds on the L side, and 5 1/2 pnds on the R side. was thinking of going up alittle on the tire pressure to get roll speed from it.
 
I see N.Y what track you racing at ? On that size track a 12 front driver would be correct for Sr class, I may have ask you this already but have you ever confirmed what others in your class are running ? now with giving up 51 lb you would be 1 less than average, Or confirm what the Sr class clone is running.
 
Im at Allegany memorial raceway, AMR in Allentown, some of the red plates are running 11 gear some 12 the Sr class clone 12 tooth, but for his weight I would say the 11 tooth would bind way to much, that's why I went with the 12 tooth, nobody says what the rear gear is if you ask, its I don't know 59 to 62, but that don't sound right to me and the gear looks bigger than any of my 58 to 60 the Sr class clones are running 12/63 to 12/68 in some cases
 
he said that was a good range could go alittle more if I wanted to, he told me to run the 12/64 and said I could go 1 tooth up or 1 tooth down the 1 tooth down didn't work, so was thinking of going the other way, because he said supposed to be in the 5400 range for red plates but he added a cam and some other things pushing the limits of the rules on this because of the weight difference, he said this motor could turn 6500 on a red plate. Its a headrush motor
 
steve10 said:
he said that was a good range could go alittle more if I wanted to, he told me to run the 12/64 and said I could go 1 tooth up or 1 tooth down the 1 tooth down didn't work, so was thinking of going the other way, because he said supposed to be in the 5400 range for red plates but he added a cam and some other things pushing the limits of the rules on this because of the weight difference, he said this motor could turn 6500 on a red plate. Its a headrush motor
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He's telling you that based on Dyno sheet ? or he's just talking ? If it's not been on the dyno he cannot tell you that with any confidence.
The same AMS that John Layfield operates ?
 
It was on a dyno, hydro I can't remember the full name he said he does two different tests, my bad it will do 6100 when pulling with the red plate, he is always at the track and watches his motors there then talks to us about them, right now getting a dover motor built for my other son, and yes that's the same track layfield operates
 
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5,170 13 65 5.00-1 33.29
5,170 12 60 5.00-1 33.29
5,250 12 62 5.17-1 32.70 ??
5,500 12 63 5.25-1 33.73
5,630 12 64 5.33-1 34.01
You improved your top speed by only .72 MPH, but the extra gear should of help to improve on acceleration out of the corners. What about lap times? I'm wondering about air density. It could have been responsible for your extra speed, but it would help your competitors to, so that would be a push.

It's called tuning, and tuning is tough! (Al Nunley)
 
The dead stop start is a killer. Try your best clutch setup at home from a dead stop and then pop on a 10 or 11 tooth yard kart clutch. I bet it takes off like a rocket. Went through this with our purple plate motor. I would do the 11 or 12 driver to help with the starts and gear accordingly. The part I’m having trouble with is even if he gets a bad start why is it taking 5 laps to catch up?
 
I have posted this many times in the past. Put your bathroom scale between a strong wall and the front of your kart. Sit in the kart, warm up the engine, and floor it. It just takes 2 or 3 seconds. Observe the reading on the scale and the reading on your tack. Adjust the clutch stall RPM and try it again. You want your clutch stall RPM to be where it produces the highest reading on the scale. With maximum torque at the rear axle your producing maximum HP at the rear axle which will give you maximum acceleration on the starts. If at this point, you are not keeping up with the competition on the starts, only two things can be at fault, wrong gear, not enough HP.

It's called tuning, and tuning is tough! (Al Nunley)
 
We ran a 12 tooth driver with a 65 rear and he got a good jump from the dead start and he walked away from them in the heat, and turned 5650 rpms, but in the feature he took 2nd but started on the poll, its when he starts behind them like 3rd or 4th that once they get the jump then he works hard to try to catch up but they get such a big jump it takes a couple laps, and one thing his cart with him in it weighs 322 where the other racers weigh in at 275 266 around that area so that's a handicap right there, im just trying to figure out how to make up that handicap, my sons drives his rear end off. I got the dyno info on my engine it goes between 5800 to 6000 rpms so I can gear it up more. was thinking of running an 11 driver and going into the 50's rear gear not shure what on like 57 58 rear if that will boost him up there. or sticking with the 12 driver and going to a 67 rear gear.
 
steve10 said:
We ran a 12 tooth driver with a 65 rear and he got a good jump from the dead start and he walked away from them in the heat, and turned 5650 rpms, but in the feature he took 2nd but started on the poll, its when he starts behind them like 3rd or 4th that once they get the jump then he works hard to try to catch up but they get such a big jump it takes a couple laps, and one thing his cart with him in it weighs 322 where the other racers weigh in at 275 266 around that area so that's a handicap right there, im just trying to figure out how to make up that handicap, my sons drives his rear end off. I got the dyno info on my engine it goes between 5800 to 6000 rpms so I can gear it up more. was thinking of running an 11 driver and going into the 50's rear gear not shure what on like 57 58 rear if that will boost him up there. or sticking with the 12 driver and going to a 67 rear gear.
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Your at 5650 with a 12/65 and need say 5900 right in the middle that would be a 12/67, so if you drop front to an 11 driver rear would be a 63 you would have to drop front to a 10 driver to get into the fifties that would be a 59, the fact that he's having more trouble when starting further back is him just not reacting as quickly to the start flag.
 
I feel your pain I race a 340 flathead class and cross the scales a 402. I would throw a 66 or 67 on the back and make sure he is either laying back and getting a run for the start or running it up their rears to keep the rpms up for the starts. Just stay dead center on their bumper you don't wanna spin no one...lol
 
racing promotor said:
Your at 5650 with a 12/65 and need say 5900 right in the middle that would be a 12/67, so if you drop front to an 11 driver rear would be a 63 you would have to drop front to a 10 driver to get into the fifties that would be a 59, the fact that he's having more trouble when starting further back is him just not reacting as quickly to the start flag.
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10/59 = 5.90
11/63 = 5.73
12/65 = 5.42
12/67 = 5.58
5,650 12 65 5.42 - 1 34 tire
Top Speed In MPH
33.56
5,900 12 67 5.58 - 1 34 tire
Top Speed In MPH
34.04
This assumes that your engine can actually gain 250 RPM. It's possible, I would try it.
 
I'd go to the 12/67 or 68 ( even though I think your way off on gearing ) IF it helps, I would leave it alone until he gets more seat time, the xtra weight sure not helping ya out, but in the end your going to find your biggest issue is being newer driver not maximizing MOMENTUM and sleeping on some starts.

Good Luck !!
 
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