TD 1905 Cylinder heads

[jgra1]

Chaps, do any of you know if the TD head is the same as a D head..?

I know camshaft, injectors are different, but what about the main block itself? I can't see it being different...

thanks


John

[KP]

I think it would be slightly different due to the std compressions ratios

[jgra1]

good thinking KP....

[jgra1]

head the same, different pistons ?

[Kowalski]

The pistons on the XUD are flat topped and actually protrude from the block slightly less than the thickness of the head gasket, i.e. just clearence so they don't clatter the head. The compression ratios are different between the D and TD by way of slightly different swirl chambers n the heads. The heads themselves are very similar but one important difference is that the TD head is made from a different alloy because it has to cope with higher combustion temperatures and pressures.

You can probably stick a 'D' head on a 'TD' block and run it as a 'D' but you can't put a 'TD' head on a 'D' and expect it to last very long.

[jeremy]

I think the inlet valve seat angles are different too. As well as counting No 1 cylinder as nearest the flywheel engineers seem to like 30 degree inlet valve seats which are used on the N/A inlets. In common with most manufacturers (even Jaguar with the XK engine in the late 40's and early 50's) 30 degree inlets soon get abandoned in the quest for better breathing and more power. (Never understood why they bothered in the first place)

[jgra1]

bu**er I brought one....

to put on a TD

glad you warned me I will put the heads alongside each other to confirm the valve angle and then abandon that project


John