MB / 3B Engine blocks / internals are they the same.

[Colin Aitchison]

Hi, probably the title gives the question away, but moving on, I am trying to free up space in the garage with a clean out as you will have seen with my for sale posts, I don't want to clear out any thing I may need in the future, I do have an MB block with pistons, oil pump, sump, crank shaft, front pulley, rear crank seal, and from memory this short engine if you like only needs a head to run but I have nothing to put it in, now round to the question, is this block, crank shaft, and oil pump the same as the Audi S2 3B engine, or can anyone confirm the differences between the two engine numbers, I have noticed that the rods I think are 136mm
in the MB same as WR, later engines use a 144mm rod (KV NG 7A 3B ABY) this will mean the crank from the MB will not fit the 3B engine but any KV or 7A will, Merry Christmas to you all.

[quattrodave]

Ok so the stroke of the MB and WR is the same as the other engines ? I thought the crankshaft would fit, if the rods are longer in the other engines this implies the difference is in the piston pin location ?

I'm pretty sure that all the engines with a 86.4 stroke should use the same crankshaft. so it should fit WR/MB/KV/7A/NG/ABY or any of the 2.1/2.2/2.3 5 cylinder engines but not the smaller 1.9 5 cylinder as the stroke is shorter,incidently the 1.9 is the same bore as the 2.1 79.5 mm so the head from a 1.9 should fit a 2.1.

[mikes2]

for some reason the MB crank is different from the others.

It's the same as the 1B / MC.

3B,ABY, RR, 7A, KV and NG all share the same crank

[msh]

That reason is different rod bearing seats - rod bearings are in different dimensions.

[Colin Aitchison]

What about the MB block can it be used in 3B or ABY?