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MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG TD TF 1500 - MG Magnette final drive for TD

Hi all.....I have bought a Magnette 4.55:1 final drive which I intend fitting to a 1950 TD at the same time I am considering fitting a Siera T9 gearbox. Will this make a good combination for travelling long distances to and from rallies that is 200 to 800km. Any suggestions or help much appreciated.

Bob
South Africa
R J Orchard

...your 5th gear will be really high...might be too high for the XPaG?
gblawson(gordon- TD27667)

In my case I got a 4.3:1 ratio CWP and am using a Datsun 5 speed. I love the setup and promote it as much as I can.
Cheers,
Bob
Bob Jeffers

Message to Bob Jeffers....thanks for your input from which datsun did you get the 210 box how do you think it will perform with the 4.55:1

Thanks Bob
R J Orchard

R J Orchard With your 4.55:1 CWP your engine will rev a bit higher than mine does but it will be a big improvement over the original gearing. My guess is that you will be turning 3600 revs at 60 MPH. in 5th gear. If you do some of the hot rodders tricks to the engine you will have plenty of go-power. Read the MG Tuning manual. I suggest stage 3. Higher compression, 9.3:1, 1 1/2" carbies, the bigger valves from the Mark II, shave the flywheel, pertronix ignition. Of course your camshaft must be in tip-top shape. I recommend the 45-5-5-45 timing that was used in the late TD's and TF's. Or better yet the roller tappet camshaft Len Fanelli is providing. He has several different grinds, your choice. If you want to go even further you can mount an extracter exhaust from Manley Ford.
Have Fun, Keep In Touch!
Bob
Bob Jeffers

RJO forgot to mention I don't know what year car it was from. When I ordered it Skyhook Engineering had a supply of the transmissions. There is on the bell housing four letter combinations that Steve Neal says are suitable for conversion to "T" series cars. The information I have says that they should have FL,FA,FS,or Fx stamped into the bell housing. I must admit that I have never looked for or found those numbers on my unit. Maybe because they get removed when the bellhousing is shortened and the new plate with the correct bolt hole pattern welded on.

However at one time I had a second unit from Skyhook and it turned out to have a different shift pattern. The fellow I sold it to didn't seem to care, he was so glad to get a 5 speed kit with all the goodies.
Cheers,
Bob
Bob Jeffers

Isn't there a point at which you are decreasing the
power by too much by 5 speed and a 4.55 rear. I have heard that it does not work well in mountains
Ellis
Ellis Carlton

To Ellis C. That's what gearboxes are for. Yes, there are some hills that require downshifting but that is true with the standard original setup. With the original setup first gear was as useful as tit's on a bull. (sorry Ladies).
Cheers,
Bob
Bob Jeffers

Hi All......thanks for the many comments. Can sombody please provide contact details for Steve as I cannot locate him via the web

many Thanks

Bob (SA )
R J Orchard

Steve Neal
Skyhook Engineering
161 Mere Point Road
Brunswick, Maine (ME) 04011
207-721-0166
skyhook@suscom-maine.net

Regards,
Jim
James Neel TD28423

RJ,
I've kept my 5.125 rear in the TD with the Sierra 9...I love the low end torque and the 5th gear gives me relaxed cruising...approx 3500RPM @ 60MPH...4000RPM @ 70...that's compared to about 4000RPM @ 60 with the old tranny...about 1000RPM difference...
Bob Dougherty

I 'm just fitting a 5 speed Sierra gearbox in my TD.I found a solution to fit the original release roller bearing of the Sierra 5 speed gearbox to the Expag engine. If anyone is interested, I add pictures in the BBS.

Klaus

Harthof Klaus

Hi Klaus I will be very interested to see your solution as I am planning on fitting a type 9 to my 1950 TD
R J Orchard

Hello.
My MG TD from 1952 makes a loud and obnoxious, when I reduce rpm and speed in the back of the transmission. The mechanic told me I should change the crownn wheel and pinion. Is it true?. I can put this spare ebay?. Thank you very much for your attention.
Merry Christmas.

http://cgi.ebay.es/NEW-MORRIS-HEALEY-BUGEYE-LOTUS-CROWN-WHEEL-AND-PINION-/390089865156?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item5ad32af7c4
Gabriel Martínez

A member of our club with a ZA has a 4.1 + a Sierra T9. He loves it.

If anything is over-geared, this is it. But he has a 1960 cc 5 brng engine.

He commutes weekly to Ottawa (from Montreal). He loves to cruise by the 'regular cars' in his Mahnette and look at the expressions of the drivers!

Gord Clark
Rockburn, Qué.
Gordon A Clark

Gabriel, if this crown wheel and pinion on eBay is for a Morris or Sprite then it is much too small to fit the TD rear axle. You need one from a MGA, MG Magnette or Austin Cambridge.
Cheers, Hugh Pite
H.D. Pite

Thank you very much Hugh. Better look for this option. Excuse me, in the post "third gear jump" I asked for information to implement your recommendation. I would greatly appreciate further review the post.

Regards.
Gabriel.
Gabriel Martínez

Gabriel
Hola!
I am changing the CWP assembly in my ZA from the original 4.875:1 to a 3.9 from an early MGB.So my 4.875 will be redundant & may be suitable for your car.
One problem may be that I will have to take the drive pinion gears from My differential & fit them to the "new" diff to fit the ZA half shafts. My knowledge is insufficient to know what splines your car has, but it is likely that you can change Your pinions into the 4.875 unit.
Someone on this site will know!
If this is helpful we can correspond outside the site by email. I hope to do the changeover in January.
David
DG Harrison

Hello D.G. Harrison.

I appreciate your offer. However, I think they should change the whole. If there is any way to do it, for me no problem to reach an agreement.

Excuse me, that car is a ZA?

Gabriel.
Gabriel Martínez

Yes a 1956 ZA. I will change the complete diff housing with Pinion etc all in place so no problem with setting up the meshing of crownwheel & pinion. (well that is the aim!) If you had my old one it should be the same operation! You need to be sure the diff assembly is the same for the TD, I believe it is!
Regards
David
DG Harrison

Gabriel, you cannot use the cmplete center section from a MG ZA Magnette in a TD. The diff setup is completely different. However you can use the crown wheel and pinion from the ZA in place of the TD cwp to get a better final drive ratio.
Hugh Pite
H.D. Pite

That's right Hugh. I just want the crown wheel and pinion, but I think the original ratio is 4875:1. So nothing will change. Or not?.
Gabriel Martínez.
Gabriel Martínez

This thread was discussed between 06/12/2010 and 26/12/2010

MG TD TF 1500 index

This thread is from the archive. The Live MG TD TF 1500 BBS is active now.