Gearing suggestions

Flanson

New member
As mentioned in another post I have non hemi bone stock predator. Running blue plate our weight is 345. Track is 1/8 mile dirt mainly flat very very slight bankimg. Track is dusty with good bite in the groove but NOT tacky. Clutch is Hillard fury with 2 black and 2 white springs. Governor is in but locked open. Finished day running 12/59 turning Max 5189 rpm.

Am I in the ball park or way off?
 

OVALTECH1

Premium User
If it’s happy at that rpm leave it. As far as clutch driver goes unless you are having to break momentum a lot and are constantly having rpm drops due to your or other drivers I’d go up on driver size. I would use atleast a 14 and use the rear gear that keeps your ratio as close as what you have now. Not sure on the Hilliard clutch but if it’s near 2400 ish rpm lockup that will put you in the game.
 

racing promotor

Moderator
As mentioned in another post I have non hemi bone stock predator. Running blue plate our weight is 345. Track is 1/8 mile dirt mainly flat very very slight bankimg. Track is dusty with good bite in the groove but NOT tacky. Clutch is Hillard fury with 2 black and 2 white springs. Governor is in but locked open. Finished day running 12/59 turning Max 5189 rpm.

Am I in the ball park or way off?
Short answer NO not in ball park, IF indeed it's an 1/8 th mile.
 

racing promotor

Moderator
Track is advertised as 1/8 mile
That's usually wrong most advertise bigger than they actually are, 1/8th mile is 660 LF or 220 full stride steps If you walk it off.
Is he able to pretty much flatfoot it and carry good MOMENTUM ? Do you know what your drops are from your tach ?
 

alvin l nunley

Premium User
14/69 would give you a very close ratio to what you have now. 13/64 would do the same. 14/69 is a good recommendation, if you can run that big a gear. The ratio difference between all 3 is only .027. That comes from my new spreadsheet calculating gear ratios using base circles. I also wonder, is that too low a gear ratio for that track?
 

Flanson

New member
14/69 would give you a very close ratio to what you have now. 13/64 would do the same. 14/69 is a good recommendation, if you can run that big a gear. The ratio difference between all 3 is only .027. That comes from my new spreadsheet calculating gear ratios using base circles. I also wonder, is that too low a gear ratio for that track?
I went w/ 14/67 and it was good. Much more faster and kept w/ the pack. We were turning 5100-5150 rpms. We hit 5200 once but I think she was driving it harder into the corner to try and make a last minute push for a position. Well I know she was because she told me she ran it harder into the corner that time.
 
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