Scott Lampert wrote:
> when i took my toploader in for rebuild the guy told me it was a wide
> ratio. What is the difference, and was this in any specific tigers?
>
> also i just ordered a cat 6 bolt slave bracket, is this a cheezy one?
>
> happy hohoho
>
> scott
> Mk1 B9472628
Scott,
The wide ratio toploader is the stock offering for the Mk II Tiger. The
box, bearings, clutches, main shaft, etc. are the same as the 'close
ratio', but the first three gears have different ratios. The close
ratio gears are 2.32:1, 1.69:1, 1.29:1, and 1.0:1 for the HEH-E first
through fourth. The corresponding wide ratio gears are 2.78, 1.93,
1.36, and 1.0:1 in the HEH-B Mk II box. The Mk II box also has a wider
bearing retainer and two sets of mounting holes for 5 bolt and 6 bolt
bell housings. Unless your s/n reads HEH-B, and has the 8 holes, it
isn't a Mk II, but will perform the same. The exception being mounting
to a 6 bolt bell housing. There have been other posts on that, as well
as the need for additional reinforcement of the CAT 6 bolt slave
bracket. This structural stiffening, with welded ribs, can be made to
work well.
The OTHER difference is performance. While the 'close' ratio is good
for the road courses, and is usually favored by racers, the wide ratio
has a h-ll of a lot better performance from a dead stop, and around
town. On the road, the 4th gears are the same, so there is no
difference. Practically speaking, the first gear in the stock close
ratio is so low that it provides little off-the-line torque. Having a
first gear shift point near 60 mph isn't very useful. The wide ratio
puts the torque on the road and gets you off in a hurry.
In normal conversation the terms 'close' and 'wide' ratio are normally
construed as 'good' and 'poor'. Ford's choice of terms isn't like the
old definitions. The difference in the ratios shows up when you shift,
and the rpm drops to it's appropriate value in the next gear.
Typically, and fast get-aways, the rpm will drop 1,000 rpm at a 6,000
rpm shift. This gives you a small drop along the torque curve, and
allows healthy acceleration. In a typical 'wide ratio' the drop may be
1,500-2,000 rpm. This could but you at a much lower torque value, and
result in poor acceleration. In this Ford case, the drop is 1,200 rpm
vs 1,000 rpm. Not really significant with our big V-8. The gears are
also well spaced, so there is no sluggishness at any gear change.
Having tried both on the same car and engine, I'd take the 'wide ratio'
every time. Even good for Auto-X, 'cause you can run it at a good
torque range in second, rather than being stuck in first at very high
rpms, or a second that is not quite in the right rpm range.
Just my opinion.
--
Steve Laifman < One first kiss, >
B9472289 < one first love, and >
< one first win, is all >
< you get in this life. >
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