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MGA Doc, Do You Know MGAs final gear ratio?

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PAUL161

PAUL161

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What is the final gear ratio in an MGA rear? Did the ratio change during any of the years? Looking into and picking up information on converting my TF rear for lower RPMs at highway speeds. PJ
 
Come on guys, I know some of you know the answer to this! PJ
 
4.3:1 right across the production run. There may have been some variants for racing (4.875, 5.125(!) )but AFAIK the 4.3 chunk was standard.

THIS is that "esoterica" stuff Tony would be able to confirm or dispute. :frown:
 
You woke me up, Paul. Where's my <span style="font-weight: bold"><span style="font-style: italic">COFFEE</span></span>?!? :jester:
 
I'm drinking it right now! :devilgrin:
 
...selfish git.... :jester:

Not sure about interchangeability from TF to MGA chunks, my WAG is if the axle splines match, it'd work. The input flange is another issue tho.

I think you're looking at an "engineer as you go" project.

Is the TF ratio that much different than the 4.3 MGA?
 
The MGA 1500 and 1600 used a 4.3 diff as standard, with 4.55 optional. The MGA Mk 2 had a 4.1 as standard.

There were also 4,88 and 5.13 from other BMC models (I've used both in the race cars) and of course the MGB 3.9.
 
"I think you're looking at an "engineer as you go" project."

Its all been engineered many years ago by the likes of Carl Cerderstrand and a booklet is available on doing the modification. The booklet is available from Moss Motors, P/N 212-350.

I am finishing the last of that cup of coffee for you Doc.
Cheers,
 
Well I guess so, Dave! :wink:

Enjoy it...


I'm not one for switch 'n swap, so you guys have the straight poop on that stuff. Last T-series car I messed with was decades ago.
 
David_DuBois said:
Its all been engineered many years ago by the likes of Carl Cerderstrand and a booklet is available on doing the modification. The booklet is available from Moss Motors, P/N 212-350.
Click to expand...

Thanks Dave, I'll send for it. PJ
 
DrEntropy said:
I'm not one for switch 'n swap, so you guys have the straight poop on that stuff. Last T-series car I messed with was decades ago.
Click to expand...

I agree. That's why our TD still has the 5.125 rear axle in it. We have driven it all over the western US since purchasing it in 1974 and have never any problems with it. 4200 rpm at 60 mph is harder on ones nerves than on the engine.
Cheers,
 
Just put an order into Moss, air cleaners, paint and Carl Cerderstrands book. PJ
 
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