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MG TD TF 1500 - XPAG block dimension

Does anyone have the measurement of a standard T-Type block from head gasket face to centre of crankshaft? I have a friend who wants to find out how much his block has been machined down in the past.

Cheers,
Bob Schapel
R L Schapel

Bob
Written in my records book--
268mm gives zero deck height with std height pistons
Sorry, that's all I can tell you
What the normal std. deck height above the piston is to add to this, I don't know
Cheers
willy
William Revit


Hi Bob,

268mm matches my calculations (not measured) using a 0.00 piston deck clearance.

Stock Block Height Measurement:
BH = (1/2 Stroke + Rod Length + Piston Compression Height + Piston Deck Clearance)

BH = (1.7717 + 7.0078 + 1.7717 + 0.0000)-inch = 10.5512-inch = 268.0005mm

Regards,

Bill
WHTroyer

Bob - There was a "Factory Block Height" thread on the MG Experience site a few weeks ago, where I measured my NOS XPEG block at 10.555" or 268+mm from crank centerline to block face. There was also a 270mm spec bandied about in an old post, measuring from block deck to sump gasket flange. See "Piston height / decked block; what to do"

Tom Lange
MGT Repair
t lange

Thanks Willy, Bill and Tom.
The same figure in records, calculation and measurement! How perfect is that!
Very much appreciated guys.


The fact that the calculations match the measurement of a NOS block and the records, suggests that originally the pistons did originally come level with the deck (or at least within a couple of 'thou). Your information provides evidence to support what we probably all assumed.

Cheers from South Australia,
Bob Schapel
R L Schapel

I carefully measured all aspecgts of my NOS XPEG long block before I disassemvbled it, and the pistons were within .001" of flush. That is meazsured with a straight edge and feeler gauge.

Tom Lange
MGT Repair
t lange

Thanks Tom,
Great information. Particularly because I assume the con-rods were NOS also? About 40 years ago I assembled an XPAG engine without checking the lengths of the rods. From memory, a couple of pistons protruded about 20 thou, one was level and the other was about 15 thou short of level. It turned out the rods were all different lengths. I guess the engine had been through some serious type of trauma before I worked on it.
Bob
R L Schapel

This thread was discussed between 13/07/2018 and 15/07/2018

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