Gear ratio 1/4 mile dirt track

Maltamirano

New member
Hi,
I searched around for 1/4 mile dirt track gear ratios but wasn’t seeing anything either the 1/4 mile, only many 1/8 mile tracks.
Setting up my built predator 212 engine for the pure stock class.
we are running on a semi banked 1/4 mile dirt track that runs pretty dry (valley hills ferry raceway). Trying to get my gear ratio set up, what are some opinions on ratios to start at? I’m using a 12 tooth drive on a Hilliard clutch. Would a 12/56 be too low? Should I jump to 12/61 or 12/63? Thank you and sorry if this thread was somewhere else and I didn’t see it.
 

racing promotor

Moderator
Stock Clone you would turn around 6500 rpm, IF indeed it's a quarter mile or even close and makes any grip whatsoever, a 18/64, 17/60, 16/56,15/52, 14/48, 13/44/ 12/41 would be close, Your no where in the ball park with a 12 driver you would need the mini gear set.
 

racing promotor

Moderator
If it's the track in Newman California I'd say it's shy of a 1/4 mile BUT it's still big and a 12/56 or bigger rear is no where close, after seeing the video and without any proven experience advise I could count on, I'd show up with a 17/60 figuring on being close early and pulling a few off the rear for the race. I'd have everything for rear along from 56 to 65
 

Maltamirano

New member
If it's the track in Newman California I'd say it's shy of a 1/4 mile BUT it's still big and a 12/56 or bigger rear is no where close, after seeing the video and without any proven experience advise I could count on, I'd show up with a 17/60 figuring on being close early and pulling a few off the rear for the race. I'd have everything for rear along from 56 to 65
So your basically saying get close to the 3.5 ratio as possible. Which obviously will get easier once I order a 17 tooth drive sprocket.
 

racing promotor

Moderator
So your basically saying get close to the 3.5 ratio as possible. Which obviously will get easier once I order a 17 tooth drive sprocket.
I don't play the ratio game BUT ya if what I offered averages a 3.5 should get you in the ball park, the lowest you could go on the driver without having the mini rear gear set would be a 16, but for that track I'd get a 17 driver and be done with it.
 

GClary

Member
Tracks differ , but at our 1/4 mile car track that we race on every now and then , unrestricted AKRA clone , 400# class I am on a 15/60ish and turn 6800 to 7100 . I probably could have used a 58 or 59 last time out and a touch more air , but the 16 driver wasn't working at all for me to keep rolling speed out of the corners . In Ohio , the 212 is a Predator and does not race legally against or in a clone class , except for a SA , BP , PAC or Open/RWYB ..
 
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