My car randomly gives out a puff of blue smoke on startup, the engine has done approx 1500 miles since run in and is running on Millers CFS 10W40, the turbo is also new, could this be down to the forged pistons, anyone else have a similar experiance using wiseco pistons?

 

Could well be, for sure.

Forged pistons cold are slightly undersized (hence their associated piston slap). So chances are small amounts of oil/oil vapour is getting past the rings... up until they have reached normal operating temp., when they'll have expanded to the correct spec.

This would also explain why forged pistons are linked with higher oil consumption too.

 

yeh, mine was same since forged, till i blew up again

 

The strange thing is that there is no slap on cold startup and it hasn't used a drop of oil since the last oil change, catch can is bone dry as well.....

 

Turbo seals or thrust bearing failing?
Valve stem seals?
Piston rings?

Condensation?
Imagination?

 

Do you know why it let go?

 

None of the above everything is new

 

Sure it wouldnt be down to the pistons. Mine has never smoked because of them.

More likely turbo seals or engine build itself.

Who built the engine? What turbo?

 

Engine built by engine tuner and the turbo is an 18G iirc

Banny

 

Oh ok - Seals sound like the most likely culprit.

 

yeah, dont panic, i over fueled it, set up adjustable fuel reg wrong

im going bk standard

 

Can you elaborate what you actually did?

Did you set to 4 bar and overwhelm an old knackered fuel pump causing it to run way lean, or something...?

 

Every seal and gasket is brand new, heads have also been overhauled, the turbo has also been overhauled by turbo technics

 

Why not ask enginetuner?

 

I have done, I've been told that some do it and some don't, something to with oil draining back down the bore when stood up, so was just wondering if there any others on here using wisecos with the same prob, everything else is spot on as it should be

 

yeh, i set the fuel pressure to 3bar but connected vacum pipe and it went to rich, over fueled and washed oil from bore, then the rings siezed and scored bore, damage so bad i had 2 buy another block and 2 new pistons, also changed all rings, i set up a parallel fuel mod that went wrong, so back to standard fuel rails and pipes and reg.

currently rebuilding

but adding more mods such as uppipe gems ecu to control fuel, gonna get mapper to set run in map in straight away before it leaves garage.

i rushed and got stung

 

Thank goodness you mentioned in bold - at least that's the reason

 

Did Slow-boy Racing build the engine?

 

No they did not it was built by enginetuner and internals supplied by Lateral Performance, there is nothing wrong with the build in any way whatsover and Im a happy customer just like all the other enginetuner customers, the above issue (no that it bothers me) is just one of the issues you may come across with a built forged boxer engine - just like some people experience slappy pistons when cold or heavy oil consumption on built engines, the reason for the post was to see if anyone else using wiseco pistons had a similar issue, above all one can't expect a heavily modified impreza to run or drive like a Rolls
Royce

 

Great post. Finally some sense in the middle of all the madness that is the pointing of fingers towards tuning companies.
As an aside, I googled subaru online shops and actually paused with the mouse pointer over Area 52. Why? They have done me no harm at all, and still have great testimonials, but those few dissenting words have obviously done some damage. Apologies to Area 52, and I did browse your site after.

Back on topic.

 

Well said there mate.
We see this one occasionally, TBH it surprises me you don't see more of it when you consider how a Scooby engine is put together. Lying on its side like it does, you're always going to get oil pool in the low spot when it's parked. I'd say it could well be worse on a new engine that hasn't fully lapped its bores in to a smooth finish. You can get oil trapped in the tiny grooves left from honing. It's a small amount, and doesn't always give off smoke, but they can if it's left for a while, or if you get condensation in the exhaust diluting the mix, and making it seem worse than it is. It's noticeably worse with large exhausts! On a cold morning it kind of hangs around. We get chance to notice these things when we have ten of them lying around..
My 8000 mile babied and mint P1 used to do it, and I didn't like it one bit when I first spotted it. When I realised it didn't use any oil at all, I stopped worrying about it.

 

the reason is most likely because the longer throw on the crank (on the 2.1, 2.35 and 2.5 engines) pushes the oil control ring past the gudgeon pin inspection hole.. if the engine happens to stop at that point when you switch it off which is highly likely, it will allow a small amount of oil to drain past the compression rings into the cylinder.. you start the engine and you get a puff of smoke.. if it lasts for more than an initial cloud then I would consider it more than just that and would need investigating why.
The fact it is not using oil or blowing out the breathers would say it is nothing to be concerned about.

Simon

 

Mine has also blown a blue puff on start up before now. But then I've also a fair bit of oil in the headers and it is breathing heavily...

EJ22t cdb, 2.35, CP pistons, Pauter rods, MD321T etc etc...

Compression tests and leak test are all what you would expect from a healthy engine but not happy with the situation. I feel it has never been quite right.

It will be taken apart to see what the issue is, then possibly building it up into an even better spec.

 

Interesting point there Simon,

As per previous post, I've other issues as well and worried I may destroy my block if it keeps going that way (also noticed oil pressure at idle has dropped from 3.5 bar to 2.2-2.5 bar). I would rather take it apart now, sort the problem and re-use as much as possible so I can spend my money on making it faster.

I will be in contact to have it remapped again once other mods are on (possibly rotated ).

 

i got a puf of white smoke from mine, but have put that down to water condensation in the exhaust.

when it 1st happends you all ways think the worst. specially after my standard engine let go.

 

Oh Engine Tuner, Ive heard bad storie's about them aswell through a member on here called 'Anger'. You have to chose your tuner wisely, as there are many cowboy's out there. Have you got warranty on the build?

 

That has put my mind at rest.
With only 24k on it and the garage saying everthing with it is fine, this closes down my nagging doubts

 

Just had mine rebuilt as a 2.1 Stroker using Lateral Internals and occasionally I see a puff of smoke on start up. Zen performance said it was nothing to worry about when they mapped it last week. Car has now done 800 miles.

Ben

 

I occasionally get a puff of smoke on startup with my T25.
Consumes a fair bit of oil and does a good impression of a diesel at startup.
If the pistons clearances are too great, are they likely to damage the cylinders ?

Reading on the cosworth USA blog page, the 2.5 block apparently is inconsistent, so needs work to get them to work with forged pistons.

 

Intresting, never heard anything negative about Alan/Enginetuner before, I take it Anger has had an engine built by Alan at some point in the past and is speaking through experiance is he?