Rb30 How Far Can You Bore

[SirRacer]

Ive got my rb30 block here all ready to have pistons bought for it however noticed on one of the pistons a marking of 10. Im presuming this means there are 10thou oversized pistons in there.

There is slight piston slap (movement in one piston) so im wanting to know what i can do with this block or is it more worthwhile to simply buy another one.

Sleeving it could certainly be an option however with the blocks around 150 bucks i dont see that being a huge issue.

[Bl4cK32]

If i remember it can be done 3 times. 10, 20 then 30 over.

Myself and Cubes went 20 thou over giving roughly 3.1Lt

[SirRacer]

If i remember it can be done 3 times. 10, 20 then 30 over.

Myself and Cubes went 20 thou over giving roughly 3.1Lt

that sounds very good and means i dont need to throw out my block

will most manufacturers of pistons stock up to 30 thou over as i sem to find 10 being the limit on what i have seen? please give me links to correct me if you can

[Bl4cK32]

I cant remeber its been so long since i had it done. It couldve even been 20, 40 and 60 thou sizes...best is to ask yer engine buider. I do know it is 3 size ups, and we went the middle one...

[N I B]

040 is a common size but i have seen 88mm,thats 2mm.

[SirRacer]

how does the thou comparison work compared to mm's

eg what is 10 thou in mm's?

[N I B]

.25mm

040 is 1mm

[Cubes]

Bl4ck32 and I had the bore thickness measured. Unsure exactly how it was measured.

On our blocks 0.040" was really as big as we would want to go, according to our engine builder.

[N I B]

Ive seen some 3/4 grout filled and still street driven,Scares me tho.

[SirRacer]

cheers for the information, certainly helps

ill take my block to the engine rebuilder tomorrow and get them to measure the pistons and see what they think. friends meant to be piecing the engine together for me howver isnt so confident on the amount of movement the pistons are making in the bores.

the next size of piston i can get is .5 oversize which would then be 20thou over meaning ive got plenty of room for movement. now to just figure out whether im going forged or na rb30e pistons and finding the part numbers (a small mission)

Edited April 23, 2006 by SirRacer

[Cubes]

Bore it to the max.. If it needs another bore/hone at a later date grab a new block.