Cog placement for ramp track with long straightaway.

[Pack76oldtown]

Our pack and council us a metal track that is the ramp type with a long straightaway. Ive read a cog of greater than an inch is better to keep speed in the flat section. Can anybody shed some light on this? Im not sure of the exact specs other than metal, center rail.
The car is set up to rail ride if that helps.

 

[Charles Studer]

Pm sent

 

[Mojo Racing]

In basic terms, the farther the weight is forward (like a 1" COG), the sooner the weight leaves the downhill slope and enters into the transition.

The farther the weight is back (like 5/8"-7/8" COG) the longer the weight is on the hill pushing your car before it hits the transition. This leads to faster speeds once it hits the flat portion on the track.

Once it hits the flat portion, it is done speeding up, it only slows down after that.

 

[Pack76oldtown]

In basic terms, the farther the weight is forward (like a 1" COG), the sooner the weight leaves the downhill slope and enters into the transition.

The farther the weight is back (like 5/8"-7/8" COG) the longer the weight is on the hill pushing your car before it hits the transition. This leads to faster speeds once it hits the flat portion on the track.

Once it hits the flat portion, it is done speeding up, it only slows down after that.

I understand all that however the long straightaway concerns me. A less aggressive cog will sustain speed longer.

 

[Brian Stanley]

The boost you get from the aggressive COG coming down the hill will be greater than the speed you will sustain from the less aggressive COG on the flat.

 

[Loud2ns]

The boost you get from the aggressive COG coming down the hill will be greater than the speed you will sustain from the less aggressive COG on the flat.

I agree, and will add that good wheel prep will sustain the speed on the flat.

 

[DerbyBoyz]

I understand all that however the long straightaway concerns me. A less aggressive cog will sustain speed longer.

I have tested this exact thing awhile ago. I wanted to see this for myself, and for me.. it was slower. There is a lot of info on this site on weighting your car. Good luck

 

[Pack76oldtown]

It seems the standard to put 12 cubes behind the rear axel. How in the world do they get anywhere close to 3/4 cog with that much weight back there. I set up at 3/4 and could only get 5 cubes back there.

 

[Jeff H.]

It seems the standard to put 12 cubes behind the rear axel. How in the world do they get anywhere close to 3/4 cog with that much weight back there. I set up at 3/4 and could only get 5 cubes back there.

Did you have the wheels all the way back (5/8 from the rear of the car?). If you have to use the stock axle placement then it might be hard to get the COG to be 3/4 in front of the rear wheels with 12 tungsten cubes in the rear.

 

[Pinewood Outlaw]

My COG are generally 1/2" or slightly less....5/8 rear axle holes with 12 cubes behind axle and 12 cubes in front...rail ridding with plenty of steer adjusted.