need help with gear ratios, stock final gear ratio's not spaced out evenly - why? Options

[jimkelly]

for me - chevy v8 - stock 2nd is fine as a first gear, but it winds out fast, as does stock 3rd, as does stock 4th, and 5th is fine, but taller would get rev's down for highway cruise-ing ( 3000 rpm at 65 +- ) on 195x60x15 tires.

my question is why are stock final ratio's not spaced out evenly?

stock
3.091
1.889
1.261
0.926
0.710

3.091 x .61 = 1.889
1.889 x .66 = 1.261
1.261 x .68 = .926
0.926 x .77 = .710

evenly would be ...

3.091
2.496
1.901
1.306
0.710

for my v8, i am thinking of course to delete cantilevered first - thus i can use a beat up slider ; )
stock 2nd 1.889
?? 3rd - i need the right gear for inbetween stock 1.889 and 0.710
4th - use stock 5th ZD 0.710
5th - use flipped H 0.59 as an overdrive gear.

how the hell do i calculate the correct final gear ratio for my 3rd gear?

looks like an R (1.080) 25:27 - or - a flipped V 27:25 - is about right ??

jim

[messix]

lets just say you are building a 4sp gear box [2=1,3=2,4=3,5=4]

with the torque of the v8 you really don't want to "close ratio" the 1 to 2 shift because you will over power the tire pretty easily [you aren't fighting aero drag at all and all power will be hitting the tire hard], so a wider ratio from 1 to 2 is better to live with. from there the stock third will match shift rpm pretty good with a 4th gear flipped h/a gear set. this will make freeway driving nice and give you a good top end.

just make sure your clutch is up to holding the power.