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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 - TD Crankshafts

The crankshaft in my 53 TD has cracked between number 3 and 4 piston. The crank failed at about 4000 RPMs. The engine otherwise was undamaged. After trying to locate a used crank and finding none for sale I will be buying a new crank for the lump. What replacement crankshafts would the board recomend. There seems to only a few to consider. The new cast crank offered by Moss and the billit cranks offered by a few other sources. I look forward to seeing what you think of them.

On the off chance that someone has a good usable crank that they are willing to sell Please E-mail me off the board

Thank You
Tom
T.L. Manion

Arguably the best crankshafts (machined fron solid) are made by a company called "Phoenix", but it is an English company. You can buy a new crankshaft from "Brown and Gammons", also an English company, and they actually obtain their cranks from Phoenix. I do not know where Moss obtain their cranks from. I know it might be expensive, but I would advocate ordering a "Phoenix" crank fron Brown and Gammons, whom I am fairly sure will despatch overseas.
I have a Phoenix crank in my TD (1380cc, stage 2 tune), and after balancing, I now rev to over 6000rpm. I should say that the balance was only marginly out, and probably adequate for road use.
Roger Wilson

To those of you that responded off board, and offered crankshafts to me, THANK YOU.

Rodger I am aware of the Phoenix crank and have hear nothing but good comments about the product. I have found a good used crank had it tested and will use it as it has never been ground, still uses standard bearings. Again thanks to all
Safety Fast
Tom
T.L. Manion

Come on Roger - what are you implying with the "but"


Happy Christmas

Jan T
J Targosz

The "but" is because T.L.Manion lives in Ohio, but Phoenix are based in England (not New England) !
Roger Wilson

To Roger,

Where is the information on the various stages of tuning? I have the David Vivard A-Series engine book already.

John
John Redman

For John Redman,
The factory published a "Special Tuning Manual" for the XPAG/XPEG engine. Reprints were available from Moss, Abingdon, and others specializing in MG's and books.
It is reproduced in the Blower Manual, and I think in John Thornley's book. If you own an XPAG or EG you should have it.
My TF 1500 (XPEG) is Stage II tuned (Compression ratio 9.5 to 1, polished and ported, combustion chamber reshaped and cc'ed, etc.) so my HP is considerably enhanced over the factory 63 HP.
Don Harmer

John, the early editions of John Thornley's book, of which I have a copy, does not contain any T type tuning data, as the book was about the prewar years; I am not sure about the recent editions. Blower may contain the special tuning data, but it is not worth buying the book for the data because for T types, it is not a very good book.
I have the data in leaflet form, and I will see if I can get it scanned.
As people have hinted, performance tuning of these cars is well worth while.
Roger Wilson

Off my shelf:
John W.Thornley, "Maintaining the Breed", The Saga of MG Racing Cars
Motor Racing Publications Ltd, London
First published 1950, second and revised edition September 1956
Appendix V: Tuning the XPAG and XPEG engines (pp.178 to 187)
Remo Peter

T.L.,

The cranks offered by Moss are not cast, but rather forged from modern 4340 ChroMoly Steel. Far better material than the originals. Moss purchased the original factory tooling and overhauled it. We have the forgings done in the UK and shipped here to the US where the final machining is done. Although I'm not sure, I would surmise the other suppliers in the UK are using our forgings for their raw cranks, as no other original tooling than ours exists. Billet cranks, of course, are yet another story.

Craig Cody
Moss Motors, LTD
Craig Cody

John,

There is an article online about tuning TD engines at

http://www.mgcars.org.uk/mgtd/mgtd_performing_midgets.htm

The article covers the different tuning stages

Jesus

Jesus Benajes

There are several tuning manuals. One published by MG, another in a book called "MG Guide" by John Christy, and another written by W.K.F.Wood. The one by Wood is more comprehensive. But, each one has something different than the other.

Blake
Bullwinkle

I'm wondering (knowing so little) if there is any way of increasing HP AND MPG. I mean the low HP to MPG ratio can't be due totally to aerodynamics.

John
John Redman

Yes, there are many ideas, which have been the basis of the engine development from the fifties until today. Improving MPG means really increasing engine overall (effective) efficiency. This can be achieved by increasing the two following efficiencies:

INDICATED (INTERNAL) EFFICIENCY:
- improving fuel-air mixture (better mixing, better vaporisation, running as lean as possible, etc)
- enhancing combustion (increasing combustion speed, improving ignition, avoiding unburnt fuel)
- increasing compression ratio

MECHANICAL EFFICIENCY:
- reducing mechanical friction losses (piston with less rings, better lubricants…)
- reducing intake and exhaust flow friction (smoother pipes, less curves,,…)
- improving design and control of auxiliary systems (better water pump and radiator fan, non-continuous actuation, …)

These actions can increase MPG, and also HP. In order to further increase HP, and here not always MPG, one can also improve

VOLUMETRIC EFFICIENCY, which means increasing induced air flow rate:

- smoother intake and exhaust pipes, tuned dimensions of intake and exhaust manifolds
- larger valves, higher valve lift, tuned camshaft
- avoiding heating of intake manifolds from exhaust
- supercharging (or turbocharging)

I surely have forgotten something, but here you can find many basis for tuning techniques.

Regards.

Jesus
Jesus Benajes

This thread was discussed between 06/12/2004 and 13/01/2005

MG TD TF 1500 index

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