gbuk
Chats A Bit
Posts: 130 
|
Post by gbuk on Aug 19, 2022 22:44:48 GMT
Following on from the sequential gearbox concept, I've been watching Hamish Racing Channel where he has overdrive on 2nd, 3rd & 4th in his lovely little TR3A. It certainly seems to work well in certain parts of his hillclimbs.
I've had it on some old Triumph 2000's where it was a switch on top of the gearstick, but his is a toggle switch on the dash that he can reach with his fingertips.
Car throttle article says they're a thing of the past now we have 6 speeds and up - but it still seems a nice idea to me on a manual box? |
|
|
|
Post by Zed. on Aug 20, 2022 10:19:43 GMT
tl,dr BUT.... overdrives are still a thing, I have a Landrovah and adding an overdrive is very popular - new items are available and new designs are being developed  in motorsport the ratio-jump could be usefull and the 'old' Laycock od units were (are?) strong had Laycock od on my Hillman Hunter GLS (Holbay) that I owned 30+ years ago - had a column switch / stalk to operate iirc  also, if you fancy sillyness, ~ 20+ years ago I used to own a Quaife 'Rangechange' gearbox   from their 2003 catndog. the one I had was an overdrive, basically a 'normal' 4 speed gearbox (strait-cut, close ratio) with another gearbox as it's tailhousing with direct drive and overdrive selected by twisting the gearstich - if you wanted to be pedantic an 8 speed / 4 speed gearbox  Rich. |
|
|
|
Post by wannabe on Aug 20, 2022 12:17:46 GMT
I wish the 5s had an overdrive - doing 4k+ rpm on the motorways for any length of time gets somewhat tiring (and expensive!) lol
|
|
gbuk
Chats A Bit
Posts: 130
|
Post by gbuk on Aug 20, 2022 12:27:28 GMT
had Laycock od on my Hillman Hunter GLS (Holbay) that I owned 30+ years ago - had a column switch / stalk to operate iirc Rich.
I had a 1972 Humber Sceptre,which I vaguely remembered having overdrive on the column, but like you couldn't be sure.
I still like the shape of the hunter styling - but I eventually traded it in for an Austin Princess 1700 - another style that I liked - Interesting project here
- an S Type engine into a princess (and a K20 into an Allegro for Jonny Smith)
Geoff
|
|
|
|
Post by Zed. on Aug 20, 2022 13:04:02 GMT
I wish the 5s had an overdrive - doing 4k+ rpm on the motorways for any length of time gets somewhat tiring (and expensive!) lol was a 5 designed for our motorways? only have the one motorway here in Wales so not much of a concern for me (except for my 25mile comute) but I drive a diesel for that Rich. |
|
|
|
Post by lowender on Aug 20, 2022 17:10:17 GMT
I had a Laycock overdrive on my Volvo 123GT, stalk on the column, it just bolted up to the tail of the gearbox. The Amazon really needed it, as it was relatively low geared. Also had a Eaton Fuller 13 speed crash box on my truck, with overdrive on the top 4. No room for one of those in a 5 though. I think a lot of 5 speed auto boxes have 5th as an overdrive.
|
|
|
|
Post by dickie on Aug 24, 2022 16:47:34 GMT
I too had a Hunter GLS with overdrive. It gave useful ratios for a 1972 car with 98 BHP at the wheels. I often used third gear and flipped in and out of overdrive on B roads. I had an ex hillclimb MGB Roadster also with overdrive, The B had a secondary dash switch that enabled the overdrive to operate it all the gears rather than just 3rd and fourth. It had warning light to ensure that overdrive was not engaged in reverse. Overdrive units will take a full throttle gear change if in good condition. I too have thought about fitting over drive onto my Eunos gearbox. But unlike others here I am quite happy running at 70 MPH in third gear on the commute home!!! ( about 3 miles of dual lane road ) My rev limit is 8000 RPM. Thats with throttle bodies and a straight through 2 1/2" exhaust system.  |
|
|
|
Post by dadbif on Aug 24, 2022 21:22:26 GMT
I had a 1968 Singer Vogue, no overdrive.
When changing the clutch I discovered the release bearing was just a solid carbon disc…
Lovely car.
|
|
|
|
Post by Zed. on Aug 24, 2022 21:51:50 GMT
I discovered the release bearing was just a solid carbon disc… Anti-static Rich. |
|
le sigh