Primary and secondary engine balance

[colinmseries]

I have been reading the closed threads on the subject of engine balance and think I have a rudimentary understanding but would appreciate your thoughts on my installation.
I am fitting a significantly uprated 2.5lt in-line four, without balance shafts, into a road car. Refinement is less important to me than reliability.
I understand the secondary balance issues will be inherent but wonder how significant you feel they may be in terms of damage to the external fixings and general reliablity.
A bit like how long is a piece of string I know, but I'm growing concerned as to what size of can I am opening.
Thank you, Colin.

 

[GregLocock]

Unless you've done something grotesque to the engine (heavy pistons, short L/r) then you should be OK up to about 6000 rpm. Above that you may notice minor annoyances like the alternator falling off.


You are in roughly the same situation as a V8 with an in plane crank - so have a look at what they do to reach the same red line as you.

Cheers

Greg Locock

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