6 replies to this topic

[The Matt]

After having my block offset bored to 73.5mm I have been looking at the bores and it seems to have been honed with a cross-hatch pattern (which is nice seeing as I was gonna give it a quick hone meself before the build).

Now afer seeing this, I have been looking into the processes involved and the theory behind it.

Firstly, I believe this process (when done correctly) can help increase engine life (giving the oil something to cling to on the bore walls). But, if it is done at the too steep an angle, I believe it can also lead to higher oil-consumption.

Sooo, is there like an optimum angle for the honing etc. If so, is this something that people should be telling engine builders? Does this optimum angle depend on engine spec, RPM used, compression ratio etc? Or is it the same optimum angle for all engines??

[Sprocket]

Id leave the shop hone on it. Honing it any more will ony open out the ring gaps that little more. But do make sure you clean the bores with paper towels till there is nothing coming off.

incidently my 74mm is actualy 73.88mm after the piston clearance was set. The piston skirt diameter being 73.8mm

[pikey7]

the optimium angle is the same for all. around 45degrees, but it doesn't have to be that accurate. The oil control ring on the piston gives you the "correct" smear on the wall.

And yeah, any tiny bits of the slightest nature of residue left over from the honing process will act like 120 grit sandpaper at 4000rpm!

[The Matt]

okey dokes, so is there any fluid I can use to wash the bore walls with too? Like for instance we have some alcohol soaked tissues that we use for cleaning at work, maybe I could give the bores a wipe over with them before the build??

[minimole]

i use parrfin to clean my engine/ pistons etc

[Bungle]

Like for instance we have some alcohol soaked tissues

no your T shirt from friday night wont do the job

beer is to sticky

[Sprocket]

Parafin is amazing and not to overpowering either. Get an air compressor and a parafin gun and it will make a good job of it. Still use the paper towels as a gauge to how clean the realy are.