Honing for new pistons!

[ben_p]

Let me just say sorry in advance for the constant threads I start re pistons/high comp etc LOL,

Ok so I am going go fit high comp woosners (12cr) I've got a set CHEAP with total steel rings,

I'm keeping the oem rods but fitting ARP fastners, as I'm keeping the rods I can re use the bearings if I mark the journals, and the pistons are standard size so I don't need to machine the block, but I think I'm right in thinking that I need to hone the liners? Can this be done as a diy? Or will I need to take the block to a machine shop and will the crank need to come out?

cheers

 

[stan*]

Stop skimping, buy new shells for a start!

The block needs honing, yes...

Yes, the crank needs to come out. You want it totally stripped.

 

[ben_p]

I'm trying to do it all for £500, the pistons have cost me £300 (new)

What you think?

 

[Fred@BTM]

you're mad?

 

[ben_p]

Lolz!

£70 for honing
£300 for rings and pistons
£50 gaskets

?
£80 bearings

 

[stan*]

honestly, you cant be tight on some stuff, and building an engine is one of the best examples.
I'd have a measure up, get he block decked (just marginally) to tighten up squish clearance. also gives you a nice fresh working surface....nothing more satisfying than building a nice,fresh, clean engine!
measure the crank pins and bearing id when torqued in their caps, to determine running clearances...maybe have the crank ground if they are on the highside..(obtaining an actual diameter to give a desired clearance is the best way, dont rely on a machine shop to just simply take 0.25mm off)

You'll likely have to grind the piston rings to set the end gaps, so again, dont skim, do it right.

Youve got yourself in a situation now, where not only are you in for a penny, you ARE in for a pound!!!
Theres only one way to do what you are trying to do, and trying to cut corners to save a few quid doesnt come into it.
Building a quality engine DOES make a difference to the power output.

 

[ben_p]

Hmmm sounds expensive, lol!
Cheers for the advice, I'll do some numbers! Doesn't seem worth it for 10hp now

 

[Fred@BTM]

told you so

 

[stan*]

10hp from increased Cr maybe, but if you build it properly you will see more.

Its worth it for piece of mind alone really...no?