3.55 rear end

[Lotus 50]

The standard gears of course make for a lot of revs on the highway. Has anyone tried 3.55 gears? RD has a used differential with 3.55 gears. Worth the change? It would only be a couple of hundred rpm.

[jono]

I did it on my Plus 2 but reverted back to a 3.77

It made a small but noticable difference on the motorway however that did not offset the slightly blunted acceleration and increased effort getting off the line, especially on a hill.

I concluded that Lotus got it pretty much bang on with the 3.77 which to me suits the car nicely.

[Billmack]

If you have 3.9 change to 3.55 rpm drops 9 percent more or less. If you have 3.77 and go to 3.55 rpm drop is about 6 percent.

[Baggy2]

I guess it depends on how you want to use your car. I've just installed both a 3.55 diff and a 5 speed Lotus gearbox in my +2 at the same time - I still have 13" wheels. And I'm very pleased with the result. Whilst on minor roads I find I don't use 5th gear as often as I had expected - the car is quite happy in the higher 4th gear. Acceleration is still fine for normal road driving and I haven't noticed any problem pulling away.
This is in a +2 used for general day to day motoring - the picture might be different in a two seat Elan possibly used for occasional competitive purposes.
I wouldn't change back.
Just my two penneth

[TBG]

If you go for a 3:1 and you have the power all is pure joy - but I have banged on about this before!!

[rgh0]

3.55 with the Lotus 5 speed works well with good acceleration off the line with the lower first and then great cruising in 5th gear on open roads ... works for me in my Plus2S 130/5 with lower profile 175/60 x 13 tyres and Australian speed limits

cheers
Rohan

[TBG]

Speed limits? What's that then Rohan!!

[elans3]

My S3 S/E has the 3.55 diff with the close ratio (2.5:1) 1st gear, and I find it perfect, no problem pulling away, and much better on the motorway. However, I can see that it may present a problem for some, with the heavier +2, particularly with a standard engine.

[prezoom]

I have a 3.55 coupled with a close ratio gearbox in my Plus2. I did notice a slight loss of acceleration from the 3.77, but not enough to make much of a difference. Disclaimer, the car is also equipped with a 2L Zetec and an aluminum flywheel. Have not yet found a hill steep enough to cause a problem pulling away from a stop. Additionally, my Sabra is equipped with a 3.55 and 165/15 tires, a ZF gearbox , with a 2.5 first gear, and has no problems with hill starts even having much less horsepower and torque, but with a flywheel weight of that of a diesel truck. Get the flywheel spinning and it will even crawl up my steep, but short, driveway at an idle. Inertia can be your friend at times.

[mbell]

I too have Lotus 5 speed, 3.55 diff but with 175/70r13 tyres. Generally find it good for the open road, I do find 2nd is a little tall slower speed driving in car parks etc but not a major issue.

[Lotus 50]

I put this post in the Plus 2 discussion, rather than technical, as the Plus 2 is heavier and might need different gearing then the standard Elan. Thanks for the information. I will stay with the current gearing.