7 replies to this topic

[muzzal 1275]

just wondering if this could be done at home if so what would be the best tools to use ?

[Rosslin Racing]

a lathe and tools, grinding stones, Jig, shot peening and balancer, plus
thats if you want to do a proper job. are you building an all out racer? if not why do you want to do this?

[mini*mad]

also would make balancing the pistons and conrods akward
id get a machining shop to do it!

[lsto]

When I was building my engine I spoke to my friend Ray Mason, who was big in building cossies and RS's back in the day... Anyway he suggested just polishing all the rough edges and casting marks off the con-rods, unless your building an all out racer you'll get more power from balancing instead of lightening con-rods, what he did say is once they are polished it reduces drag within the sump and could possibly gain a few horses, wether this is correct I don't know, but they do look pretty once polished up...

[MRA]

When I was building my engine I spoke to my friend Ray Mason, who was big in building cossies and RS's back in the day... Anyway he suggested just polishing all the rough edges and casting marks off the con-rods, unless your building an all out racer you'll get more power from balancing instead of lightening con-rods, what he did say is once they are polished it reduces drag within the sump and could possibly gain a few horses, wether this is correct I don't know, but they do look pretty once polished up...

Polishing all the rough areas, if polished in the correct direction will reduce the risk of fatigue. I think you have this the wrong way around, balancing unless it is super high revving will not increase the horse power, and then only by reducing frictional issues within the rotating parts.

Lightening will NOT increase power, what it will do is increase the rate of change of the engine revs, in other words, allow the engine to rev faster and increase acceleration, this is on a diminishing return with reliability. also the effects will reduce the higher up the gearbox you go.

Recent studies are concluding that if the parts are too polished they actually increase drag within the sump, most race cossies by the way would be dry sump.

And yes they do look good when all is built up

[lsto]

When I was building my engine I spoke to my friend Ray Mason, who was big in building cossies and RS's back in the day... Anyway he suggested just polishing all the rough edges and casting marks off the con-rods, unless your building an all out racer you'll get more power from balancing instead of lightening con-rods, what he did say is once they are polished it reduces drag within the sump and could possibly gain a few horses, wether this is correct I don't know, but they do look pretty once polished up...

Polishing all the rough areas, if polished in the correct direction will reduce the risk of fatigue. I think you have this the wrong way around, balancing unless it is super high revving will not increase the horse power, and then only by reducing frictional issues within the rotating parts.

Lightening will NOT increase power, what it will do is increase the rate of change of the engine revs, in other words, allow the engine to rev faster and increase acceleration, this is on a diminishing return with reliability. also the effects will reduce the higher up the gearbox you go.

Recent studies are concluding that if the parts are too polished they actually increase drag within the sump, most race cossies by the way would be dry sump.

And yes they do look good when all is built up

I stand corrected

[muzzal 1275]

thanks for the replies guys but sounds like this is one for the pros
the aim for the build was just to do as much as i could on it
myself
thanks again

[tiger99]

You can do the polishing yourself, along the length of the rod, NEVER crossways. It really does improve the fatigue strength.