cg10 pistons in cg13

[chie]

has anyone ever dont this and was there any problems with valves hitting piston crowns etc? cheers

 

[Craig]

Not been done in UK that I am aware of, I have seen a Jap picture of a piston with a nice valve-shaped mark in it from this but I think that he had 0.7mm hgasket. You will have to do what I was resigned to and put the pistons in and then manually see the clearance...

 

[Titch]

I'll get them to you soon Lad!

 

[chie]

hmm ill try it with a std gasket, and turn it iver by hand and if worst comes to worst ill machine some pockets for the valves or make a thicker gasket

 

[Dr Zoidberg]

out of interest whats the benenfit of doing this?

 

[Ian]

the CG10 pistons are rounded iirc (unless the CG13 are domed then they are flat), anyway it takes the compression ratio up. From something like 9.5 to around 10.2. Watch out with them if youu are running high lift cams also.

 

[Dr Zoidberg]

ah cheers ian

 

[chie]

cg13 areeflat and cg10 are domed

 

[RIK]

wont they be lighter aswell??

 

[Craig]

Pockets is best, but dunno how much room you have in the crown and surly a thichker HG asket defeats the point of doing it, if you could reduce endfloat then you shouldbe ok

 

[Ian]

wont they be lighter aswell??

if anything, they will be heavier.

 

[RIK]

thats a bad thing!! why put heavier parts in?

 

[Craig]

Cos it will raise comp to 10.1 ish

 

[RIK]

but it takes more effort to move them if ther heavier,wont this cancel out any improvement?

 

[Craig]

Nope, the higher comp k10s are quicker than the normal ones

 

[Ian]

anyway, they wont be THAT much heavier, probably like 200g a piece.

 

[Craig]

I will weigh one if you are really desperate to know...