While stripping my expired race engine,I discovered that a con rod marked for rear use was used in the front cyl and its corresponding rear cylinder was using a front con rod.
This had obviously been done to match the con rods with the crank.
It had been working the finest and had nothing to do with my engine failure.
Anyone one got an opinion on this?
The front cyl with the rear con rod was the one that ate a valve.
I have a matching con rod(rear) to replace it,as it didn't seem to make a difference, I reckon it's a
good substitution.

Indiana Jones wrote:The front cyl with the rear con rod was the one that ate a valve.
.

i think that was more to do with the fact that you force fed it,
not so much the rear rod in the front cyl.


i don't have a clue as to what difference it would make but i am interested to see what answers you get.

hope you get it sorted soon.

I have read somewere i think on this forum that it is imperative they are installed in they'r correct places,
I believe its to do with an oil pickup hole in the rod.

The oil pick ups were in the correct position,the con rods were turned 180 deg on the crank.
Was wondering why it was difficult to read the numbers on the rods when I had the sump off.
They were facing the wrong way.

I wouldn't have thought it would make an iota of difference, provided the oil holes lined up. It's not like the dimensions will change from front to back.

Exactly, that's the way they'll be going back coz that's all I have.

Interestinger and more interestinger.
The big end bearings all have 2 extra oil holes in them,so each bearing has 4 oil holes.
I wonder are these modified or are they bearings from another compatible model.
Edit: Single hole bearings are OE, all new bearings have two holes.
I love learning new stuff.

Hi,
The rear conrods are 2g's heavier than the front. So at speed the gyroscopic or rotating mass will be magnified. Without seeing the engine myself couldn't say that caused the failure but just wanted to say that there is a difference between the front and rear rods but only by weight.
Mike @ BMC Racing.

So you will get crankshaft imbalance then,There is always a reason why these component's are marked.

This is what happenes when you missplace the con-rods with the crank!

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