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4K Pistons

Featured Replies

G'day all,

 

I'm hoping someone on here might be able to help me out,

 

I'm building a ke30, nothing to insane, just 4k conversion with a nice cam on a nice set of watanabes. she'll be a daily, but she'll do it in style.

 

Spent the morning putting the engine together, came to the last piston and found a crack... its on one of the tangs, and chances are one of my housemates stepped on it while it was out of the car :/...

and there usually such good blokes :bash:

 

So here I am, hoping that someone might have a single, decent standard 4k piston they'd be willing to part with? or alternatively, know of a supplier that'd be willing to sell a single piston... its a long shot, but I'm pretty desperate.

 

also... on a related note, could i use a 3k piston... or are they a different bore?

 

Cheers

 

Tuns

why go up a bore size if you don't need to?

 

40 bucks is good for a new piston. id be looking into that.

 

if not i can help you out with a motor i have sitting here.

 

cheers, andy

 

 

I'd put a set in anyway, step up a bore size or two.

I'm with you philbey a complete set is they way to go. But also no need to go bigger if the bore is in good nick. Yes you can buy singles if they have em, but I wouldn't mix match manufactures. Not many manufactures will make a piston to excact oem specs. Rings are usually different let alone weights or material specs.

In saying that what brand are the pistons you have? I can send you in the right direction if I know what they are.

 

Stu.

Edited by kickn5k

the pistons is suspected of being cracked by being stood on, and as its just a 4k, i reckon a single will be fine :wink:

  • Author

thanks guys, was just looking for a quick fix to get it going there but upon reflection new set is probably what we'll do.

 

although i do have a 3k and ive since discovered they share the same pistons, forgive me for being cheap but would there be any dramas swapping those pistons onto the rods we already have or is there some engine building voodoo that i don't know about?

 

tuns

 

edit: reading the last post answered that question so i think ill just do that, thanks guys

Edited by tunsafun321

  • Author

or dropped, or kicked or used like a maracca... not 100% how it happened but it did

the old piston maracca, one of my favourites :)

Watch out with the 3K piston.

 

Have a look at the skirt. Have been told the 4K pistons have a section of skirt clearance for the counterweight on the crank due to the longer stroke.

 

Never really bothered to check myself. But maybe something to watch out for.

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