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Not a 5 speed discussion

PostPosted: Wed Feb 15, 2012 12:23 am
by Famous Frank
OK, All my friends know I'd like to have a 5 speed so I can have OD (Overdrive). Here in the Atlanta area, the quickest way to get around is via the expressways, and if you are on the expressways here you will most likely be doing 80 mph or more. The 5 speed question is still in question.

So here is a new question. Does anyone know why no one has come out with an Overdrive 4 speed conversion? There appears to be a number of companies that make gear sets,.............close ratio this, close ratio that. Straight cut gears for the track. Why can't we have a gear set made up that would use the semi-close ratios for 1st thru 3rd and then have an OD 4th?

If I want to accelerate hard, the first three gears will do that. They'll bring me up to over 100 mph. Then I could just dump it into an OD 4th for cruising.

Also, and I apologize and I'm also emabarrased to say, as this is probably covered someplace but what is the "Rocket" transmission? Is that the same transmission that is used in our Elans?

Many thanks! Famous Frank

Re: Not a 5 speed discussion

PostPosted: Wed Feb 15, 2012 12:47 am
by ardee_selby
Famous Frank wrote: Also, and I apologize and I'm also emabarrased to say, as this is probably covered someplace but what is the "Rocket" transmission? Is that the same transmission that is used in our Elans? Many thanks! Famous Frank


Frank,

Did you see these? Includes description of the "Rocket" configuration.

http://dl.dropbox.com/u/45450049/box%20clever%2001.jpg
http://dl.dropbox.com/u/45450049/box%20clever%2002.jpg
http://dl.dropbox.com/u/45450049/box%20clever%2003.jpg
http://dl.dropbox.com/u/45450049/box%20clever%2004.jpg

(Ref: elan-f15/box-clever-mag-article-t23357.html?hilit= box clever)

HIH - Richard

Re: Not a 5 speed discussion

PostPosted: Wed Feb 15, 2012 2:04 am
by Famous Frank
Richard, thank you very much. I had never seen that. Shame none of those boxes ever came with an OD 4th.

I'll be printing those pages out and will bring them to the garage!

Thank you again! Frank

Re: Not a 5 speed discussion

PostPosted: Wed Feb 15, 2012 9:03 am
by worzel
Hi Frank

An outfit called Godfrey hill Gearboxes used to do exactly what you describe. I don't know if they still exist and, if so, if they still can do this. They were (might still be) based in the south of England. Apparently they were renowned aws transmission experts. I had an article featuring their work- unfortunately I didn't keep it.

regards

John

Re: Not a 5 speed discussion

PostPosted: Wed Feb 15, 2012 9:41 am
by ardee_selby
worzel wrote:Hi Frank

An outfit called Godfrey hill Gearboxes used to do exactly what you describe. I don't know if they still exist and, if so, if they still can do this. They were (might still be) based in the south of England. Apparently they were renowned aws transmission experts. I had an article featuring their work- unfortunately I didn't keep it.

regards

John


Interesting John,

Was new to me. After a bit of Googling...

Status - "Dissolved" :(

However, a couple of references describing their work:

http://www.c5martin.co.uk/marlin/Berli% ... rboxes.pdf
http://www.david.mirylees.btinternet.co ... chTips.pdf

Richard

Re: Not a 5 speed discussion

PostPosted: Wed Feb 15, 2012 10:54 am
by ardee_selby
Post script:

The second link (above) refers to the Lotus 7 application.

Anyone on here have experience of such a gearbox conversion?

Richard

Re: Not a 5 speed discussion

PostPosted: Wed Feb 15, 2012 6:02 pm
by CBUEB1771
Famous Frank wrote:Does anyone know why no one has come out with an Overdrive 4 speed conversion?


Keep in mind that one ratio is always going to be 1:1 given how the four speed gearbox is designed. Richard's links are interesting in the description of the "3+E" conversions. The only way to do this leaves you with the "overdrive" ratio being selected with the gear lever in a position other than where fourth gear is normally selected. It is the normal third gear location as these conversions are described.

Re: Not a 5 speed discussion

PostPosted: Wed Feb 15, 2012 9:34 pm
by Famous Frank
I'm finding this very interesting! The "3+E" Conversion. I wish Godfrey Hill gearboxes was still in business. I'd be ordering a gearset now !

I've got enough power to pull away from most cars in 1st and 2nd. If it's a slow gear change to 3rd, I'd learn to live with it!

Does anyone know how to get intouch with Mr. Hill. I don't know when the doors shut but usually when a business closes, there is still inventory laying around. Or someone bought the assets. Somewhere I bet there are the parts I desire laying on a shelf someplace!

Thank you everyone for your information. Now can we find a set? Something with 2.9x first gear and maybe a 0.8x OD. Is this set laying in someones garage not being used?

Famous Frank

Re: Not a 5 speed discussion

PostPosted: Sat Feb 18, 2012 10:07 pm
by Ross Robbins
Hi Frank,
Does this mean you have given up on the five speed idea I checked out in Denver? :shock: My engine is out now and tranny separated while I replace main seals so if you need something measured off the transmission or bellhousing I can get that done.

Re: Not a 5 speed discussion

PostPosted: Tue Jan 23, 2018 12:31 pm
by trw99
In case anyone finds this thread during a search, here is some additional info on the interesting 3+E gearbox, written by Graham Arnold for the Autumn 1983 Club Lotus News.

Tim

Re: Not a 5 speed discussion

PostPosted: Tue Jan 23, 2018 2:06 pm
by gus
I don't think I wold like that conversion, the 2-3 change is one of the most used when accelerating and the best part of the gearbox, and having to do an up over down would stink

Re: Not a 5 speed discussion

PostPosted: Tue Jan 23, 2018 5:14 pm
by Lyn7
Hello all. In the quest to find Godfrey Hill, he or a subsequent company still exist. His middle name is Godfrey and he started a very successful and now well known UK company called BGH Gearboxes. Alias Brian Godfrey Hill !
He will be quite elderly now and I do not know if he is still working or involved with this company.
Frank it is not possible to do overdrive fourth gear, as it is direct drive i.e. one to one. That is why "Godfrey" did overdrive third. He also raised the first and second ratios so the gaps were closer. Quite clever apart from the strange gear stick action. I have one on the shelf and third gear ratio is 0.85 to one. I cannot remember the other ratios for now. Sorry the box is not for sale...
Cheers, Lyn.

Re: Not a 5 speed discussion

PostPosted: Tue Jan 23, 2018 5:33 pm
by snowyelan
These have got to be close to fitting in the backbone tunnel....Where's my tape?

http://www.odspares.com/phdi/p1.nsf/sup ... ent&part=4

Re: Not a 5 speed discussion

PostPosted: Tue Jan 23, 2018 6:20 pm
by Davidb
I'll save you the trouble!
p1060888.jpg and

Too wide by several inches.

This is the usual Laycock overdrive as fitted to Volvos, TRs, Healeys etc.
Somebody on this forum said that they had seen an overdrive from an early fifties Sunbeam fitted to an Elan-I dunno anything about that though.

Re: Not a 5 speed discussion

PostPosted: Tue Jan 23, 2018 6:45 pm
by alan.barker
trw99 wrote:In case anyone finds this thread during a search, here is some additional info on the interesting 3+E gearbox, written by Graham Arnold for the Autumn 1983 Club Lotus News.

Tim

I have copies of the quarterly Club mag from Jan 1984.
I also have some copies of the very large mag like a Newspaper size around 1980/1981.
Is the copie your talking about the smaller quarterly mag.
Thanks for info
Alan