Question for the techies....
Question for the techies....
Author
Discussion

SXS 

Original Poster:

2,068 posts

269 months

Monday 4th October 2004
quotequote all
If final gear was 1:1 - would that be ok to drive at 70mph on the roads? how would it feel?
I know its a lame question, but I've never driven a final gear ratio 1:1 car before as daily runner... just wandering how bad? or ok it is?

SteveB*

31,988 posts

264 months

Monday 4th October 2004
quotequote all
I think 5th gear is 0.79 to 1! (oops...I thought I was in the Chimaera area...not sure what car you are referring to)

Not sure what your question means. But if you mean can the car be driven sensibly within legal limits the answer is absolutely.

>> Edited by SteveB* on Monday 4th October 21:59

shpub

8,507 posts

301 months

Tuesday 5th October 2004
quotequote all
Go to www.tvrbooks.co.uk and the tyre FAQ and download the tyre size calculator. Select or put in tyre sizes, gear ratios etc and it will tell you what revs correspond to what gear.

1:1 ratio is effectively driving in 4th. Yes driving at 70 will be fine but the fuel economy (such as it is) is a lot worse than 5th as I suspect the engine may well be on cam and trying to drink the fuel.

Steve
www.tvrbooks.co.uk

TVR Slag's BiL

5,282 posts

275 months

Tuesday 5th October 2004
quotequote all
Is 4th not 1:1? So IIRC it would be like driving everywhere in 4th????

OK if ur in a Mini I guess?

tvrgit

8,489 posts

281 months

Tuesday 5th October 2004
quotequote all
revs at 70 mph (or any other speed) also depends on the diff crownwheel / pinion ratio

Paul.B

3,949 posts

293 months

Tuesday 5th October 2004
quotequote all
Are you asking......

"Is a final drive (Diff) ratio of 1:1 OK?"
or
"Is a top gear (5th) ratio of 1:1 OK?"


Would make a whole lot if difference to the answer!

Paul.

prunus

135 posts

274 months

Tuesday 5th October 2004
quotequote all
Surely if final gear is 1:1 then it means that it's a score draw doesn't it?

Depending on who it was up against and whether it was home or away are the more important questions to be answered.

Exactly how fast that 1:1 draw is driven is of secondary importance, IMHO.

SXS 

Original Poster:

2,068 posts

269 months

Tuesday 5th October 2004
quotequote all
Hmmm, sorry, I meant a 4 gear setup, and the fourth having a 1:1 ratio....

Anyone heard of a manual gear cockpit switchable diff? and are they any good? and would it make life better or worse?

harrow_chim

514 posts

312 months

Wednesday 6th October 2004
quotequote all
Overdrive unit is effectively a switcheable diff. They fit onto the back of the gearbox - very popular for 60s and 70s sportscars. As far as I know they are specific to the gearbox to which they are attached.
Nick