cptcaveman

Sorry guys these are probably going to be really newbie type questions, but here goes...

My dealership have just told me that I have a cracked piston, in my my06 sti (its not down on power but occasionally overheats and uses a lot of oil). Apparently the heads are fine, and i'm hoping its hasn't done any other damage (scoring etc), at least they haven't mentioned any.

Its the second time they've had the engine out in 8months (previously to replace the head gasket). I'm not knocking the garage they seem pretty good, but the car itself just feels like a dud (only had it about 14 months and the engines been out twice, on its second set of rear shocks etc..).

My question is, its still under warranty at the moment (extended). I can hopefully let them replace it under warranty, but I get the feeling it will happen again not too far down the line. If I can convince them to do it, can I just replace the pistons with forged replacements or will I need to start thinking about other things like the rods etc.. I realise it will probably void the warranty, but while they've got it stripped, it seems like a good time, and really I just want the piece of mind that it is less likely to happen again.

Stupid question maybe, but if I did go that route, would it cause it to run differently, would I need a remap or anything else?

I've got no mods on it, but some time in the future i'd like to at least get a replacement exhaust with sports cat, and a remap, in its current state I'm not sure this particular one would take it.

Lastly, I'm trying to avoid spending a fortune, i've just bought my first flat, and the credit card has taken a hammering, I was planning a proper forge build much further down the line, but with no pay rises and no Christmas bonus this year, money as they say is too tight to mention.

Any thoughts greatly appreciated

fastmike

iTrader: (4)

Let them repair it under the warranty and enjoy not having to pick up the tab........ picking up the tab will come soon enough my friend.

When you decide to have a forged build it,l be more than the pistons being changed

fastmike

iTrader: (4)

Let them repair it under the warranty and enjoy not having to pick up the tab........ picking up the tab will come soon enough my friend.

When you decide to have a forged build it,l be more than the pistons being changed

F1 CJE UK

iTrader: (8)

yep i agree having half a forged setup is a waste, save your money and get it done as one big job ( next year for me)

seem bloody unlucky tho i had head gasket issues and since then decided to hold off any other plans till rcm could build me a new lump

cptcaveman

Thanks for the responses guys, your both probably right

Just seemed like a good time while the engine was out, but I could definitely do with not forking out the cash

Thanks

TheVoices

iTrader: (5)

I take it the car is a Hawkeye 2.5 STi ?

If so Subaru seem to have a problem with the pistons on this engine, might be worth looking at the cost of a set of forged pistons whilst the engine is in bits ?

At least this way you aren't paying for the labour and if you discuss your concerns with the garage they may be able to get you the forged pistons at trade or make a goodwill contribution towards the cost ?

If you let them fit another set of standard pistons under warranty it costs you nothing but what if they fail again out of warranty and maybe cause some bore damage at the same time ?

You are looking at engine out again just to do the pistons at a later date and you will be paying the labour charge !

From the research I have done, most people rate the standard crank to 500 bhp+ and the standard rods to 400+, the pistons are the weak link.

You might be better replacing them now, no real need for replacement rods and the only 'better' crankshaft would be a billet steel one (usually cost £2k+)

Unless at some stage you want to go for 'monster' power, the forged pistons would give you some peace of mind and maybe prevent a future expensive rebuild ?

As a bonus, if you do then decide to up the power at a later date, you know that the engine internals will handle it.

I know what I would do if it was mine !

cptcaveman

That was kind of my feeling, I'm not after monster power at the moment (not sure I ever will) but I like to have a car I feel I can drive enthusiasticly when the chance appears, at the moment if they replace the standard piston, after reading about similar problems other people have had, I don't think i'd have that kind of peace of mind.

At least if I shelled out a bit now, it might make it less likely in the future, and as you say i'm saving myself some labour costs. Only thing is it would void my warranty, but if I let that lapse, and then have another problem down the line....

hmmm i'll have to have a think, but thanks for the responses.