5 speed to 4 speed conversion

[jono]

A friend of mine had a plus 2 with 3.55 diff and close ratio (long first) 3 rail box.

He said it "absolutely made the car" and he had no issue getting off the line (though clearly not as easy as with the 3.77). I have it on my wishlist of mods as soon as the fuel injection conversion is done this winter

Currently I have a 3.54 diff in my plus 2 with a semi close box and it works nicely on the open road and is great for touring but I hanker after closer ratios

Jon

[l10tus]

Bad news update !

I checked my Diff. Ratio last night and it's 3.54.

This means the car is as good as it's going to get (gearing wise) - so for me, that's real bad news, because I feel I just can't drive it the way it is set up - it's reving it's ba--s off at 50mph.

Very disappointed !

Hope the 5 speed will help a little, otherwise it's going to be used regularly as a "Mantle Piece Display" only !

Kev,

IMHO, Don't even contemplate a 3.9, let alone a 3.7 diff, - it's purgetry !

[rgh0]

Bad news update !

I checked my Diff. Ratio last night and it's 3.54.

This means the car is as good as it's going to get (gearing wise) - so for me, that's real bad news, because I feel I just can't drive it the way it is set up - it's reving it's ba--s off at 50mph.

A 3.54 elan on 155 / 80 x 13 tyres does 18.5 mph per 1000 rpm
so 50 mph is is about 2700 rpm - hardly reving its ba--s off ????

Are your tacho and speedo all wrong or do you just drive a diesel truck the rest of the time and anything above 1800 rpm you consider to fast?

cheers
Rohan

[TroonSprint]

I was about to say the same Rohan. My car has the 3.77 diff and its perfectly fine for UK road use. At 50 mph I work the revs out for mine to be around 2860 rpm. With the Twin-Cam engine its just getting into its stride and feels quite comfortable. I haven't been very far in mine yet, but did take it over to near Edinburgh, a journey of around 75 miles. Sitting on the motorway at 70 mph (3770 rpm approx) was quite alright. The wind noise was greater than the engine noise.

Of course its very different to my diesel modern car, and also to my V8 MGB. Both of those pull like a traction engine from 1000 rpm, but run out of puff at a bit over 4500 rpm.

Mike

[l10tus]

Rohan,

Know where you are coming from.

My diesel cruiser does 55 mpg at 1100 rpm = 65mph.

But Elan's instruments are just guess work , so may be doing 50 at 3500revs.

The tachometer swings like a metronome.

Speedo is more fun to watch than a kids bouncy castle. ( yes, I've installed new cable, and refurbed the head unit)

All pretty much guesswork!

All I know is, the car is only really suitable for a short, 'round the block' sort of trips, mainly used to annoy the neibours with the noise from the exhaust !

But hey- Ho, it looks pretty!

Regards,

Phil.

[mbell]

If you've got a smartphone,why not install one of the many car speedo apps and use GPS to confirm what speed you are actually doing at high revs.

If its a noise rather than actual engine rev problem you could also consider adjustments to the exhaust to make it quieter. Or look at improving the sound deadening.

[l10tus]

Revs are the issue.

The gearing is just too low to use comfortably, surrounded by modern traffic.

It's just not nice, especially on anything other than 'B' class roads.

I can see why people go for 5 or 6 speed conversions.

We've all seen that old classic, struggling along the dual carriageway, just causing a traffic jam emmitting noise, blue smoke in all, - just a bit embarrassing !

I'm tending to go out for a 2 - 5 mile trip, either under cover of darkness, or at times when I know roads are quieter.

I just know the neighbours say :' there goes noisey again' ! When I go out in it.

The revs wake the Devil.

[jimj]

Phillip, your disappointment disappoints me, the standard Sprint gearing is fine other than for, say, long motorway journeys. On our S3 we have a 3.54 diff. and the Voight 5 speed which is ideal for long journeys but, like all "improvements" there are compromises and it moves the driving experience a bit more away from a proper classic Lotus Elan.
You just can`t beat the sheer pleasure in driving a standard Sprint and if you aren`t smiling while you drive then give yourself a good slap.
Jim

[l10tus]

Jim,

Slap me twice !,

But first:-

Oh no !

You've now cast aspersions on the ?2000 +, worth of Voight conversion, pray tell us - what's the issues there??

(P.S. Don't hold back - I think we can handle the truth !)

My Options seem to be reducing by each reply !

Regards,

Phil

[billwill]

The highest numbered ones that fit are 3.9:1 are they not?

As fitted on some 26R cars.

[TroonSprint]

The tachometer swings like a metronome.
Speedo is more fun to watch than a kids bouncy castle. ( yes, I've installed new cable, and refurbed the head unit)

I don't know why. The original gauges on mine work well. I put a small circuit board in the tachometer to make it compatible with electronic ignition and it doesn't swing at all. The speedo is 44 years old and still working as it should. No, it's not rock steady like an electronic one, but at 70 mph it only swings by one or two mph each side which is quite acceptable.

Regular readers will know that this is my first experience of an Elan. At the age of 67 I've waited a long time to give one a try. Driving home quite fast last night I began to see what an Elan is all about. Snicking through the Ford box and keeping the engine spinning was quite exhilarating. As for the way it goes round a roundabout in second gear with the power on - just amazing.

Mike

[jimj]

Phillip, you misunderstand, the compromise with the Voight conversion is that it takes away some of the classic Elanness. It depends how important that is to you,
We have an S3 as described with Miller shafts too. Ok, first is a bit low but the clutch is really light and progressive, the change is smooth and the whole car is easier to drive. We use it mostly for long, often continental, journeys so that`s "better".
We also have a Sprint which is absolutely factory spec. so not as quiet and more of a challenge to drive smoothly, and I like that aspect a lot, a great deal, in fact, more.
Live and let live, do as you like, but I wouldn`t want to change the character of any classic car, the character is the whole reason for having that car. Personally, I just can`t understand anyone fitting modern mechanicals, it`s missing the whole point.
Jim

[toomspj]

Phillip

I guess your best option is to park the car on a plinth or sell it. My Elan Sprint (3.54 diff) happily cruises at 90+ mph, and I use it to 6500 rpm all the time - it's what the car's about. Sure, the engine needs rebuilding a lot more frequently than a 'lazy' car, but mine has still lasted more than 15 years from the last time it was apart before I had a refresh earlier this year. And you're right it is revving to well north of 5,000 rpm while cruising which is ridiculous by modern standards - but we're driving a 50 year old car by choice. I think it is a testament to the Lotus design that you can still expect to compete with modern sporty cars

Back in the 1980's I used to drive fairly frequently from Sussex to Aberdeen in it - absolutely brilliant even with a standard 3.77 diff.

The only thought I have, is what tyres are you running? I use 165/70 x13 on the standard 4 1/2" rims which keeps the gearing quite tall.

[CBUEB1771]

The highest numbered ones that fit are 3.9:1 are they not?

The 3.9:1 is the greatest reduction CWP set supplied by Lotus in normal production. Quaife/Tran-X supply CWPs for the English axle in 3.545:1, 3.777:1, 3.889:1, 4.111:1, 4.444:1; 4.714:1, 4.857:1, 5.143:1 and 5.286:1 reductions.

[l10tus]

Billwill,

I think my cars' 3.54:1 Diff was a standard factory fit on the Sprint and later +2 ?

Probably indicates where Lotus where going with regards later gearing design ?

The higher gearing route had obviously begun !

I know Ford did a 3.55:1 ratio (fitted to the Escort 2 range - that apparently fits the Saisbury diff case ?) - that was as high as it was available at the time, and in fact, IMHO has never been improved upon.

Regards,

Phil.