Changing Pistons

[ZILR-34]

hi guys

I have a R32 gts-t and had the engine reco'd about 2months ago to standard spec. I made a big mistake not putting in forged pistons in. my question is which might sound abit dumb

is it possible to change the piston's with out taking off the head again and pulling out the motor? e.g., like put the car on a hoist and taking off the gearbox, oil pan and oil pump. And unblot the crank and pulling out the pistons.?

cheers

bill

[TiTAN]

Just take the head off. There is more to it than you think.

[skylinekid]

nah mate head has to come off. cant drop them out the bottom. generally u have to take motor out again put on a stand take head off take sump off and one by one unbolt bigends and slide pistons and conrods out the top. a fair ole job to wanna go and do now. basically strip it back to a bare motor pretty much. if u got bucket loads of money go nuts.

Edited July 10, 2008 by skylinekid

[ZILR-34]

but is it possible? wat kind of problems will i run into?

[GTRsean]

No problems just cost time and money for labour, new gaskets, sealant etc, but you will need to hone the bores to suit the forged pistons to get piston to bore clearance right and bed in rings as far as I know.

[skylinekid]

and while apart again may aswell chuck is some h beams lol...

[GTRsean]

and while apart again may aswell chuck is some h beams lol...

Ha ha, true you are, they are cheap these days.

[260tech]

hi guys

I have a R32 gts-t and had the engine reco'd about 2months ago to standard spec. I made a big mistake not putting in forged pistons in. my question is which might sound abit dumb

is it possible to change the piston's with out taking off the head again and pulling out the motor? e.g., like put the car on a hoist and taking off the gearbox, oil pan and oil pump. And unblot the crank and pulling out the pistons.?

cheers

bill

Hi there, apart from cast pistons, what kinda big mistake? Effective life of motor after big mistake? Like can yurun with a de-rated motor for the intended purpose for a while (like 40k's) or is the intended purpose gunna foobar it? If the latter is the case then pull motor out, strip it down & fit gear that will achieve yor purpose. Most cost effective option.

Cheers GW

[blind_elk]

Pistons can only come out / go in through the top of the block.

You need to have the head off for that - obviously - and the sump off the get at the big ends.

[ZILR-34]

my car is already pushing 232rwkw's and i dont think it will last to long. i know that u have to put the pistons through the top. but i cbf pulling everything out again. i dont see the difference would be if u go through the bottom?

cheers

bill

[blind_elk]

How are you going to get the ring compressor to work installing the piston from underneath?

And why would you want to disturb the crank bearings when you remove the crank?

[James_03]

Your probably better off sourcing another bottom end, then building that up in the mean time.

At least that way your not without the car for weeks on end while you take it all out. Could probably just sell your bottom end on them to re-coupe costs. If its making that power now and the tune is good there is no reason why it shouldn't last.

Cheers.

[tridentt150v]

but you will need to hone the bores to suit the forged pistons to get piston to bore clearance right

+1 on the hone for new rings

[NickR33]

its an RB20 dude, you will be fine at 230rwkw's... just make sure the tune is good... not a big mistake IMO

Roy will post here soon... 260rwkw on standard RB20... plenty of track work and he drives like a bank robber hehe... you will be fine:)