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MG MGB Technical - T9 Long 1st Gear?

I'm going to install the Ford T9 transmission to replace the worn 3 synchro (non od) gearbox in my '66 B. I'm looking for feedback on the long 1st gear option that Hi Gear offers. Do you like it? Still glad you got it? Wish you didn't? Will I miss that quick 1st gear?
Thanks, Bernie
bhall1

If you're talking about the 2.89, go for it you won't be disapointed
It's a good useable gear and you actually get somewhere in it not like the other revvy go nowhere options
It's roughly the same ratio as the std box in a Lotus Elan
I replaced my Elan box with the bullet box with the 2.54 1st gear and while that's ok for what I'm doing,,for normal road use I would much prefer the 2.89-1st gear
willy
William Revit

Yes, Willy. According to the Hi Gear website it's a 2.98:1 first gear ratio. They also offer a 3.65:1 which is very close to what I have now. The first gear on the 3 Synchro is about 3.63:1. So it's a considerable difference.
bhall1

I requested the 2.98:1 first gear option for my MGA when I fitted the Hi Gear kit, having always found the standard MGA/MGB Mk I 3.65:1 first gear tediously low. (I have an MGA Mk II and an MGB Mk I).

With the additional torque of the MGB over the various MGA models, I'd say go for the 2.98:1 first gear ratio (though I personally think the circa 3.3:1 Mazda first gear would be better still, and with a nicer shift action than a Ford T9).
T Aczel

Bernie,
when I fitted a 1950cc engine to my MGA a couple of years ago, I took the opportunity of having my T9 5-Speed box overhauled whilst the engine was out of the car, because the box was jumping out of 1st gear on the over-run.

The gearbox had standard Ford Sierra ratios before this and I so decided to upgrade it whilst I had the 1st gear problem fixed.

I had always been slightly irritated that standard 5-Speeds 1st and 2nd gears were so low and that there was such a big gap between 2nd and 3rd gears.
(I know the standard Sierra box has a very slightly higher 1st gear ratio than the standard MG box but it was still too low for my preferences)

My original engine was an 1850 3-bearing MGB motor and it had enough torque to start in 2nd gear if you wanted to.
The most annoying thing for me was that when we were climbing those miles-long mountain passes (like the Grand St Bernard in the Alps), the car would gradually bog down in 3rd gear but, when you changed down to 2nd gear you could soon be revving well over 5000 rpm to maintain the speed.

So I decided to fit higher first and second gears and at the same time fit heavy duty bearings from the Sporting Close Sierra 4X4 2.8 Litre gearbox.

We decided that with the 1950cc power we could easily cope with these higher ratios and this is the list of ratios we fitted.
First Gear 2.66:1
Second Gear 1.75:1
Third Gear 1.26:1
Fourth Gear 1.00:1
Fifth Gear 0.82:1

These have proved to be excellent and the ratios now are pretty evenly spaced with no large gaps. The high 1st gear is no problem and it easily copes with 1 in 4 climbs with no problem at all.

To be honest, the power and torque of this motor are such that it will now pull 3rd gear up almost any slope and so I could have coped with the standard ratios, because 2nd gear just isn't needed so much anymore.
But it is still nicer to drive with the more evenly spread ratios.

I somewhere have a list of all the various MGA gear ratios plus the standard Sierra box ratios to compare.
I must admit that I don't have the MGB gearbox ratios but I would expect that the power to weight ratios of both cars will be very similar.

Hope that helps.

Cheers
Colyn

Colyn Firth

B ratios are on this site - https://www.mg-cars.org.uk/MGB/mgbspec.html

And I can put up the various T9 ratios here, just ask, or they'll be in the M&S Technical Archive as I recently(-ish?) put up a post(s) (or two) of them.
Nigel Atkins

Bernie
The 2.98 will be fine, you will love it
Although your 1st gear now is 3.6?, the last of the Bs ran the same ratios as the v8s with a 3.33 1st gear and did it easy
You won't be disapointed, just press the button and do it
willy
William Revit

Thanks everyone for you feedback! I feel a lot more comfortable now. Cheers!
bhall1

This thread was discussed between 15/02/2019 and 19/02/2019

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