Lotus Elan

6 speed gearbox for the Elan

PostPost by: RogerFrench » Tue Sep 06, 2011 2:34 pm

Bob wrote:No I have made sure Pistons and Valves dont get mixed up, I have a Omex rev limiter fitted currently set at 5500 but I might change that to 6000 RPM
Bob


How will that help with a mixed-up down change, though?
1967 Elan S3
1972 Europa Twin Cam
2005 Elise
User avatar
RogerFrench
Fourth Gear
Fourth Gear
 
Posts: 617
Joined: 01 Dec 2009
Location: Richmond, TX

PostPost by: GrUmPyBoDgEr » Tue Sep 06, 2011 4:59 pm

elansprint71 wrote:
GrUmPyBoDgEr wrote:I hope that the 4th, 6th confusion doesn't happen on down changes?
That can push an engine well over its safe rev limit & cause valves to make freinds with pistons.

John


Would that situation not require a 7th gear? :roll:


6th down to 4th?
Beware of the Illuminati


Editor: On Sunday morning, February 8th 2015, Derek "John" Pelly AKA GrumpyBodger passed away genuinely peacefully at Weston Hospicecare, Weston Super Mare. He will be missed.
User avatar
GrUmPyBoDgEr
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 3151
Joined: 29 Oct 2004
Location: Burnham-on-Mud

PostPost by: freddy22112211 » Tue Sep 06, 2011 6:02 pm

..praps someone would like to enlighten me (not usually difficult to do!) - but I found the (lotus) 5 speed on my sprint to be perfect - what advantage does 6 gears give? (On my Renault however the 6 gears are also perfect, but its a diesel).
Gordon
User avatar
freddy22112211
Second Gear
Second Gear
 
Posts: 191
Joined: 21 Sep 2003
Location: Ulm, Germany

PostPost by: Spyder fan » Tue Sep 06, 2011 6:09 pm

GrUmPyBoDgEr wrote:
elansprint71 wrote:
GrUmPyBoDgEr wrote:I hope that the 4th, 6th confusion doesn't happen on down changes?
That can push an engine well over its safe rev limit & cause valves to make freinds with pistons.

John


Would that situation not require a 7th gear? :roll:


6th down to 4th?


John,

Surely you know that on a standard 6 speed gate that to get straight to 4th from 6th you would have to be short shifting ( up to neutral and back down to 4th) 6th to 3rd would be a much more plausible mistake and far more interesting regarding the social life of the valves and pistons.

Bob, As Roger mentions at the top of this page, your rev limiter won't stop a mechanical over rev such as John is describing, I would have thought 5,500 rpm was a little on the low side in any case, I remember the noise as intoxicating when my twinc approached 6500, a quite safe rev limit for a well maintained engine.

I share Pete's view regarding the roll out and publicity of the 6 speed gearbox, why aren't they releasing more information? It surely can't be because they are trying to protect their idea, the market for this sort of thing is too small to worry about if a few people make copies in their garage or shed, if it's a well built and engineered product at a sensible price then most people will buy from them rather than risk bodging something up themselves. The only person I know who has a home brewed 6 speed MX5 gearbox in his car is Tony Penzoti ( Elan BDG ) who personally engineered his own solution, but it took many many hours of work to get right.

Regards
Last edited by Spyder fan on Tue Sep 06, 2011 6:32 pm, edited 1 time in total.
Kindest regards

Alan Thomas
User avatar
Spyder fan
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 2519
Joined: 11 Jun 2009
Location: Kent country & Sussex seaside UK

PostPost by: Spyder fan » Tue Sep 06, 2011 6:22 pm

freddy22112211 wrote:..praps someone would like to enlighten me (not usually difficult to do!) - but I found the (lotus) 5 speed on my sprint to be perfect - what advantage does 6 gears give? (On my Renault however the 6 gears are also perfect, but its a diesel).
Gordon


Hi Gordon,
I think the original idea was to give a lower 1st gear for stop start crawling in modern traffic and a higher top gear for cruising/motorway. This is what I read at Castle Combe a couple of years ago when the gearbox was first advertised.

The 1st ratio in a Lotus 5 speed box is described by some as not ideal for the fastest getaways and some say the gear change quality is poor. I haven't experienced a 5 speed Lotus gearbox, so those are not my personal views, however the MX5 6 speed gearbox which we all believe this conversion to be based upon has a very nice spread of ratios that suit the peaky nature of a twincam with the advantage of a very similar gear change quality to a 4 speed 3 rail bullet gearbox.

I have a 5 speed MT75 gearbox in my +2 and it suits the Zetec very well, not much can beat it from the lights and 85mph is 3750rpm in 5th, the extra torque from the engine copes with the appalling ratios where a Lotus twincam would struggle.

Regards
Kindest regards

Alan Thomas
User avatar
Spyder fan
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 2519
Joined: 11 Jun 2009
Location: Kent country & Sussex seaside UK

PostPost by: elansprint71 » Tue Sep 06, 2011 7:02 pm

GrUmPyBoDgEr wrote:
elansprint71 wrote:
GrUmPyBoDgEr wrote:I hope that the 4th, 6th confusion doesn't happen on down changes?
That can push an engine well over its safe rev limit & cause valves to make freinds with pistons.

John


Would that situation not require a 7th gear? :roll:


6th down to 4th?


But you would already be in sixth, so by doing a u-shaped down change the confusion would be either 4th or 2nd and an across the gate down change either 5th or 3rd. The only 4th vs 6th confusion could be an up-change. :|
elansprint71
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 4092
Joined: 16 Sep 2003
Location: Cheshire, UK.

PostPost by: bcmc33 » Tue Sep 06, 2011 8:42 pm

I was sort of interested in the MX5 conversion on the basis that it had 5th & 6th as overdrives - I got this impression from Tony (Yellow peril BDG Elan) when we spoke at Donington. Clearly my understanding was wrong.

The Lotus 5 speed with the lower ratio 1st gear compared with the 4 speed suits my 3.54 diff for much better fast starts, and I don't seem to notice a wider gap to 2nd as I'm running an engine with 120 lbs ft of torque at the rear wheels. Most of my driving seems to be in 3rd & 4th where I can keep it on the cam very easily.

I went to Donington last weekend on the M42/A42 where cruising at 70mph was 3000rpm in 5th. I came home across country where 3rd & 4th is music to my ears.

So, in conclusion, I can't see me having any advantage in using a closer ratio 6 speeder - so I won't bother making enquiries.
Brian Clarke
(1972 Sprint 5 EFI)

Growing old is mandatory..........Growing up is optional
User avatar
bcmc33
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1847
Joined: 10 Apr 2006
Location: Aldridge, West Midlands, UK.

PostPost by: alexblack13 » Tue Sep 06, 2011 8:58 pm

I agree with Brian here and see no need what so ever for a six speeder. Like Brian, out in the country is mainly 3rd and 4Th with an occasional slip into 5Th..

The trip down to Donington was a treat with approx 85mph at 3,300 rpm. Sat nav' confirmed the speedo to be surprisingly accurate!
I am very happy with the conversion, which is proving (so far) to be Well worth the effort. Thank goodness!!

Happy days!

Cheers guys.. 8)
Alex Black.
Now Sprintless!!
User avatar
alexblack13
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 2357
Joined: 17 Oct 2007
Location: Fife Scotland

PostPost by: GrUmPyBoDgEr » Wed Sep 07, 2011 7:25 am

Pete!

Sorry, just another one of my mental blocks! :oops:
Happening more frequently now I'm down at sea level :roll:

John
Beware of the Illuminati


Editor: On Sunday morning, February 8th 2015, Derek "John" Pelly AKA GrumpyBodger passed away genuinely peacefully at Weston Hospicecare, Weston Super Mare. He will be missed.
User avatar
GrUmPyBoDgEr
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 3151
Joined: 29 Oct 2004
Location: Burnham-on-Mud

PostPost by: Spyder fan » Wed Sep 07, 2011 7:37 am

alexblack13 wrote:I agree with Brian here and see no need what so ever for a six speeder. Like Brian, out in the country is mainly 3rd and 4Th with an occasional slip into 5Th..

The trip down to Donington was a treat with approx 85mph at 3,300 rpm. Sat nav' confirmed the speedo to be surprisingly accurate!
I am very happy with the conversion, which is proving (so far) to be Well worth the effort. Thank goodness!!

Happy days!

Cheers guys.. 8)


Sorry Alex,
As mentioned by others this thread is long and tortuous in places and I'm sure you have mentioned this already, but which conversion do you have, 5 speed Lotus or another gearbox?

Regards
Kindest regards

Alan Thomas
User avatar
Spyder fan
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 2519
Joined: 11 Jun 2009
Location: Kent country & Sussex seaside UK

PostPost by: freddy22112211 » Wed Sep 07, 2011 7:53 am

.. point of 6 speed gearbox
Alan,
1. ... lower 1st gear for stop start crawling in modern traffic
The lotus 5 speed 1st gear is quite low enough. Perfect as well for slipping the clutch on starts at the traffic lights and leaving everything a quarter of a mile behind - even big bikes if the rider is not completely awake at the time (or BMW M3s).
2. I also never found this poor quality change that everybody talks about. It's probably not as slick as the old ford 4 speeder, but I can't see that this, in a road situation, is important. Perhaps for racing.
3. As regards gaps, I believe that 1st to 2nd is supposed to be a bit large - never found this at all - the twin cam has a large power rev range.
4. The only 'advantage' I can see would be for outright top speed on the flat (not that interesting for me) - my car was rev limited in 4th, and the same speed could be reached in 5th (on the flat). A gear between would have given a slightly higher speed - on the flat - downhill in 5th it went much faster anyway.
5. Having even one more change I see as a big disadvantage, although I suppose you could miss gears out when you felt like it.
Gordon
User avatar
freddy22112211
Second Gear
Second Gear
 
Posts: 191
Joined: 21 Sep 2003
Location: Ulm, Germany

PostPost by: elansprint71 » Wed Sep 07, 2011 8:15 am

Well, in light of the fact that there appears not to be a "cruiser gear" I don't see the point. If you read reviews of the Elan going right back to John Bolster you will find a demand for a much higher top gear for Motorway cruising. A decent six-speed would offer this, lower gears at about the same ratios of the currently-available five speed boxes with an 6th cruiser gear for use when needed... let's not re-start "the overdrive debate".

I once had a FIAT Strada Abarth which was a brilliant hot-hatch, went like shite off a chrome shovel but I could tell no difference between fourth and fifth, rev the balls off it in fourth, slam it into fifth- no difference!

Out of interest, anyone know what diff ratio the MX5 uses? :wink:

I might see if i can get an extra gear in my avatar, seven is not enough. :twisted:
elansprint71
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 4092
Joined: 16 Sep 2003
Location: Cheshire, UK.

PostPost by: bcmc33 » Wed Sep 07, 2011 9:38 am

freddy22112211 wrote:2. I also never found this poor quality change that everybody talks about. It's probably not as slick as the old ford 4 speeder, but I can't see that this, in a road situation, is important.

I think we have to agree to disagree on this point. The Lotus 5 speed gating is absolutely crap - simply because it doesn't have one for 1st to 4th gears.
I'm now used to it, and find it OK, but not ideal.
The only saving grace is that the changes are much slicker than any of the 4 speeders I've driven.
Brian Clarke
(1972 Sprint 5 EFI)

Growing old is mandatory..........Growing up is optional
User avatar
bcmc33
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1847
Joined: 10 Apr 2006
Location: Aldridge, West Midlands, UK.

PostPost by: Spyder fan » Tue Sep 13, 2011 4:37 pm

Ref: What's the point of a 6 speed gearbox when a 5 speed (Lotus or MT75 etc) is probably just as good or better.............

Maybe the point we are overlooking is that most of us have 4 speed gearboxes and that properly engineered upgrades to provide a higher cog or two are thin on the ground hence the interest in this product. Lotus 5 speed gearboxes are silly money and even sillier when you need to rebuild them, MT75 gearboxes have unsuitable ratios for standard tune twin cams and the gearlever moves back by 70mm or so.

The 4 speed is fine with the right diff up to a point and that point either appears at the speed where we are all spoiled by the cruising refinement of modern cars (short diff ratio) or at the traffic lights where we are embarrased by a Fiat 500 (long diff ratio).

That's quite a few points I know :wink:
Kindest regards

Alan Thomas
User avatar
Spyder fan
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 2519
Joined: 11 Jun 2009
Location: Kent country & Sussex seaside UK

PostPost by: Bob » Tue Sep 27, 2011 8:14 am

Hi,
I have read all the arguments but just to put in my 5 penny worth, I have just come back from France and 886 miles in an S4 with a 6 speed box and a 3.55 diff wheels are 5J*13" on 165*70 Tyres, it returned about 32.5 miles to the gallon, (Strombergs) I did have a couple of issues but nothing to do with a gearbox they another story. I cruised down the Peage at 70 (3250 RPM) or so most of the way back, Saumur to Caen, the trip down was on N and D roads.

I have never tried a 5 speed but I promise this 6 speed suits the Elan very well, the best thing is the gear stick is in the right place, and just look the same as a normal 4 speed. Slipped into 6th on a Peage it just comfortable to drive, and I can hear the CD and I am a bit "mutton chop", but Jonny Cash at 70 is OK.
Bob
S4, S2 and a +2 Zetec on the way
User avatar
Bob
Second Gear
Second Gear
 
Posts: 152
Joined: 13 Mar 2009
Location: Kenilworth, Warwickshire
PreviousNext

Total Online:

Users browsing this forum: No registered users and 2 guests