LD200 1st and Top Gear Difference?

[Craig Henry]

What is the difference between a 1st gear and top gear in a LD200 gearbox? I was told the 1st has a boss on it making it wider but I can’t see any difference in the on-line Hewland manual cross section views. I would like to use a 1st gear ratio for second.

Thanks for the help.

Craig

[D.T. Benner]

In the flesh (Steel)? you can see the difference. Try Craig Taylor at Taylor-Race.com He can tell you if the ratio you are looking for is avail. from Hewland or Webster. In my 5 speed LD-200 1st. gear (from a 4 speed) becomes 2nd. so 1st. is something else again! Ain't gearbox tech FUN!!

[kea]

In the LD200 4-speed, the first gear ratio, is a second for the 5 speed. It is common to own two gearsets with the same ratio, but only one is a top gear, the other has a wide hub on the layshaft gear for placement as 1st.
Keith
Averill Racing Stuff,Inc.

[Craig Henry]

Any possibility I could have a machine shop surface grind the hub on 4-speed 1st gear down to make it work as a second gear ratio? I have no idea what the impact will be on the service life but I would think the teeth are the hardening treatment priority. I can see why not many newer cars with LD200’s are autocrossed – not many low speed gear choices and no 8:31 R&P option.

[D.T. Benner]

OK now I see what you are trying to do. What about using a much smaller rear tire (dia.) to raise your engine speed?

[kea]

On the LD200 1st (or 2nd- 5speed) gear, the boss has the spline to engage the layshaft inside. If removed, besides not being able to fit all the way up the shaft, there would be no spline to lock it to the shaft.
Do you follow me?
Keith

[HazelNut]

there is an "auto-X" first gear for the LD200. The first gear it part of the layshaft. I believe tehy might ahev couple ratios like this. My FF has one in its ld200 and it is (for a race car) tree stump pulling low, i pretty much only use 1st around the paddock in that car and 3 speed it on track.

[Craig Henry]

Thanks everyone. Taylor’s staff and Keith have both confirmed what I wanted to accomplish is not possible. The available 13:37 fixed first will work fine and is not the problem. Finding a reasonable slide on “top” gear for second without dropping 1600 RPM is. There are several decent slide-on 1st gear ratios available that would be nice for 2nd but unfortunately they work in the first gear position only. Installing a 9:31 R&P moves the peak MPH down a tad but does nothing for the 1600 RPM drop problem. An 8:31 R&P is not available. Taylor can have a custom gear ratio made but a quantity order is needed and obviously this option would be expensive. The old MK-9 never looked so good…