jameswwt

Hi Guys,
hoping to get some info on what gear ratios is great for uphill run & track which produce beefy low to mid range torque?
My current gearbox : Evo 5 Gsr
Engine Rev : Max 7500

1st Gear =
2nd =
3rd =
4th =
5th =

Thanks

sparky

iTrader: (1)

By "uphill" do you mean Hillclimb competition which is popular in the British Isles?

kouzman

iTrader: (6)

i find the stock EVO IX 5 speed gearbox quite short with gears very close between them...

For example, for drag racing sucks in a way because 3rd and fourth are quite short, that's why many change them from the USDM EVO VIII...

I think this could be a good solution if you are on a budget...

DaveK

iTrader: (21)

If money was no object, you'd gear the car so that it hits the rev-limiter in 5th gear on the fastest part of the road/track. Have first gear chosen so that you'll still be in the powerband pulling out of the tightest hairpin on the track, and then have an even stack across the middle three gears.

Dave

sparky

iTrader: (1)

I am with you about redlining in 5th on the fastest part of the track right at the braking point. However, I am not so sure about being in the middle of 1st gear when exiting the tightest hairpin. To me at least, it would depend on what the tightest hairpin exits onto. And that would depend on the particular track layout and configuration. I just don't think that I'd want that as a general rule for all track configurations. It depends on the engine's power band as well. In general, I only want 1st gear for putting around in the paddock area. On the track, I don't want to know anything about 1st gear after the start.

sparky

iTrader: (1)

What will be the top speed that the car will be seeing in these uphill runs and on the track as well? What exactly are you meaning when you ask about beefy low to midrange torque? Could you expand on this a bit please?

DaveK

iTrader: (21)

Come run Pikes Peak. With a 35r turbo and cornering speeds thru the "Ws" you're high enough in 1st that applying the throttle on exit boils the tires. Keeping it in 2nd results in falling below the boost threshold.

So, my ideal gearbox would have either a taller 1st or a shorter 2nd.

Keep in mind there aren't too many hillclimbs where your turbo will have that problem...13,000 foot elevations are a *****!

Dave

sparky

iTrader: (1)

Do you know what the ratios are in your current gearbox and what the final drive ratio is? Do you happen to know how many hundred RPM the engine jumps up on each downshift and how many hundred it drops on each upshift with your current gears? I am just trying to get a feel for what you've got right now.

Does your engine have a relatively narrow power band? Is it a stock displacement Evo or a stroker motor? How about cams? I guess that the cams must be fairly mild if you'll only be taking it up to 7500, huh!

sparky

iTrader: (1)

O.K., I guess that I bit off more than I can chew. But, I just didn't get the impression that OP would be running Pike's Peak. The Peak is definitely unique and a car that is set up for that particular venue might not be what he is looking for.

I agree with you on the desirability of a tall first gear and relatively short and tightly spaced second and third gears though.

sparky

iTrader: (1)

He'll definitely be wanting a close ratio box though and the GSR ratios are not where it is at as they are a bit too widely spaced. I am not sure if his box is a JDM GSR box or a USDM GSR box. At any rate he'll be wanting closer spaced cogs if I am reading him right.

sparky

iTrader: (1)

To the OP...Any close ratio rally or competition 5-spd. box worth its salt, is going to have a 1:1 5th gear. That way setting up for different top speeds on the fastest part of various tracks is just a matter of swapping to a different final drive ratio. I think that the GSR box and the USDM 5-spds. in general, are not fitted with a 1:1 5th gear. Instead, they are overdriven units. I may be mistaken about this since I don't have a GSR box in my Evo so I am not familiar with the GSR transmission's particular gear set.

jameswwt

Hi Sparky,
im more on a uphill climb type and the reason i said abt beefy low end torque is bcos whenever my ride enter & exit an uphill corners i hope i could provide me enough power (torque) without down shifting til 2nd gear.

jameswwt

1) Will try to check on the gearbox ratios and will check on the rpm drop & up while downshifting and upshifting.

I am running a GT3076R, GSC S2 with BC retainers + springs, JE pistons & BC I-beam rods...360awhp...

todd6027

iTrader: (10)

5 gsr box last 3 numbers either w5m51-1- x6a/x6a1/x7a/x7a1

1st 2.785
2nd 1.950
3rd 1.407
4th 1.031
5th 0.761

final gear ratio 4.529


5 rs box - w5m51-1- z6a/z6a1/z7a/z7a1

1st 2.785
2nd 1.950
3rd 1.444
4th 1.096
5th 0.825

final gear ratio 4.875


what a lot of guys use is the rs box with 4.11 final gear ratio

jameswwt

Have check and ive a W5M51-2-X6A1 with a final gear ratio 4.529.
What is the different of 4.529 vs 4.875 & 4.11???

Thanks