5 Speed Box or 3:55 diff

[mark030358]

Hi all,
Once again thanks for the great feedback. Took another trawl through Alex's excellent thread and found he did actually post a drawing of the flywheel bush, question is what's the best material to use. I have uploaded the drawing again, hope there is no copyright

One thing is that thickness 0.410". ??

thanks
Mark

[john.p.clegg]

Looks like 1" in total...

John

[Craven]

Overall thickness = 0.512 straight part = 0.410 inch.

[mark030358]

Latest question, are the internals (gear ratios etc) of an Elite (later model) the same as the +2 five speed ?

cheers

[mbell]

Yes, same Austin Maxi gear set.

[mark030358]

Thanks, been offered a box very cheap, might buy it for spares.
Cheers

[mbell]

If I was offered one I'd buy it...

For price comparison check http://lotusbits.com/

[mark030358]

Thanks for that link. Think I have a steal with this spare box then...
cheers

[mark030358]

Another question.
Reading Alex's thread I couldn't figure out the best way to fit the exhaust. So what do most people do (note I will be keeping the standard external slave cylinder) so is it...

a) Under the box
b) Parallel to the box

thanks
Mark

[nmauduit]

Another question.
Reading Alex's thread I couldn't figure out the best way to fit the exhaust. So what do most people do (note I will be keeping the standard external slave cylinder) so is it...

a) Under the box
b) Parallel to the box

b) around the box and back into the line (under would be too low) - fwiw if using a ready made "standard" exhaust a bit more fettling than usual is required (bending, probably with some heating - I opted for cutting and rewelding).

ps: there are a number of threads on 5-speed gearbox conversion, and I also found reading the Hollnagel paper quite useful...

[john.p.clegg]

I fitted mine then got underneath with a stout tube ( BSA fork leg stanchion if I remember correctly ) slid in the two pipes and gently prised them away from the box...

John

viewtopic.php?t=35356&p=241176

[mark030358]

Thanks again guys.
A couple of questions about the box...

a) when in neutral does the shift lever biased to the 3rd/4th gear rail? i.e in neutal and you push forward does it engage 3rd?
b) as noted 5th gear is stiff with the normal spring and requires a good tug to get to out, what prevents accidental engagement of reverse, i.e. if you pull straight back too hard?

thanks
Mark

[nmauduit]

b) as noted 5th gear is stiff with the normal spring and requires a good tug to get to out, what prevents accidental engagement of reverse, i.e. if you pull straight back too hard?

well, that point is a sore one with mine, and to this day I regret having let one of the usual suspects mess with the gearbox (not mentioning the hefty fee I was charged for). I have since added a couple alloy washers to make the detent spring lighter, but it only marginally improved, and when hot the 5th is still hard to disengage, to the point I don't use it for track days, and on highways I make sure I take it off long before the toll booth. There is a growing list of thing I'll have to check when I get it out, but so far I just drive it as is.

To answer more to the point, I've had to recourse to pretty strong pulls on the initial test drives, mustn't be good for the inside but nothing has snapped. Yet.

a) should be like standard gearboxes I guess (1 to 4 behave and lock/unlock normally, neutral quite free and pull lightly to the middle of 3-4 )

[mbell]

A) there is a spring for 5th/rev but not 1/3 so the stick just floats between 1/2 and 3/4. I ve added a spring to mine so that the stick centers on 3/4, it also removed side to side play in 1/2.

B) stiff 5th is common issue, I also changed the washer under the dome nut to reduce the preload on the 5th detent. Quick job that can be done from under car with minimal loss of fluid, no need to drain the box.

I don't think there is anything peventing rev being selected but never had a it happen or felt I was likely to happen. Adjusting the detent help a lot in avoiding this.

[c.garde]

Gents and nerds,
In a discussion a couple of years ago I relayed my experience that a reduction of the strength of the dome spring at ca. 1/3 effected a marked improvement of the gearchange . Might even be further reduced .
The lh plunger assembly spring ( top of 5 gear housing ) will prevent accidental engagement of rev. as it throws the lever into neutral.
To go directly from 5th. to rev you will have to overcome the plunger all the way through neutral. This will also necessitate a deliberate pressing down on the lever .
Normally you will just pull the lever backwards ( no side pressure to overcome plunger spring , no pressing down )) and end up in neutral , not in rev.
Same goes from the rev . position: With the push at the lever you will end up in neutral .
Bear in mind that the dome/spring combination was adapted from the maxi box . And this had a very long gear lever to overcome the general sloppiness in the transmission of input. - at the same time introducing even more . I dont think that Lotus gave this a second thought re the absurdly heavy engagement of 5th / rev..
I will be very interested to hear details of the added spring for 3/4 position please.
C.Garde