Whats the Diff between Close and Wide ratio?

[BenBaron]

Whats the Diff between Close and Wide gear ratio? and which is best for a cob?

cheers

Ben

[kdavies3]

That's going to be dependent on what diff ratio your running really.

A close ratio gear set is exactly that, a set of gear ratios that that are quite close together, I.E. to help the the engine in its optimum rev band as you change through the gears.
Often used in rally / race cars with high revving engines that are tuned more for power than torque.

A wide ratio box is where the ratios are more spread, more suitable for engines that have a wider torque spread I.E. most V8s.
You'll probably have an over driven 5th or 6th gear. Maybe as high as 0.82:1 or even 0.6:1 like on a T56.

Hope that helps

http://animatedgif.net/flags/-flags-uncat/Wales.gif

Kev Davies
Dax, 383ci Chevy Stroker, Tremec TKO
South Wales

:tu :tu

[Bowtie]

Try this link, it's quite informative...

http://www.5speeds.com/ratios.html

[BenBaron]

Hi Guys,
Im looking at getting a four speed toploader, Havent got my diff yet so I can get that to suit, so presumably from what you have said I should be looking for a wide ratio then......


cheers

Ben:tu

[BenBaron]

Read it, re-read and its still straight over my head! ;(
Im gunna put a posting on the us site to see what people use over there with 351w.....


cheers

Ben :tu

[MetaJacko]

Hi Ben,

I have a top loader close ratio connected to a 3.31 diff with a 428ci.

I think the basic difference is that 1st is nearer to 4th.
IE its quite high.

I've found it works well for me and I pull off fine in 1st (with very little wheel spin)
and can run up to 50 before I change. I then find I have good acceleration up past 100

This link gives more info on the ratios

http://www.davidkeetoploaders.com/torqueandgear.htm

Your decision may be dependant on your engine torque, I'm getting over 400 Lb/Ft.
(Don't know exactly and I need to get the car dyno'd)

But you may find close ratio gives you to high 1st gear (unless you use a high diff I guess)

Paul

[BenBaron]

cheers Paul,

good to know actual examples out there, Ive been reading the us site all afternoon and its like your self and Kev (I think) have commented that it depends on what diff you have as well...
Combinations seems to be CR with 3.54 and WR with 3.07 diff which give the same either way, and again it seems to depend on what I want it for (hate those problems) :}

cheers

Ben

[MetaJacko]

Hi Ben,

Just remember that 4th is 1:1 on both so close with
higher dif will end up with a lower top speed.

Paul