I have recently brought a gruppe 2.7 stroker converted type r and have noticed there is some smoke comming out of the exhaust and the engine is a little noisy on start up from cold..Once the engine is warm the engine quietens down and there is no smoke when the engine is restarted is this ok or the start of something serious?any info would be appreciated.cheers.

here is a link with info on the engine if it helps.

http://www.gruppe-s.com/Subaru/submo...S800SB-WPC.htm

 

guessing its got forged pistons, my classic with wiseco forged pistons did it for first minute or two, also got a puff of smoke at start up, worst case scenario is its worn rings

 

yes they are forged pistons,were your piston rings worn or is it common with forged engines?

 

Quite common with SOME forged engines. Bit noisier than a standard engine. Unless it's burning oil when warmed up then unlikely anything to worry about. If it is then could be rings as mentioned above or valve seals

 

it doesn't seem to be burning oil its just the initial start up from cold so hopefully should be ok , but if it is the rings or valve seals what will it cost roughly does anybody know?

 

What turbo you running?

I have seen it with certain garret based turbos whereby after being stood, say overnight, they release a bit of oil throught he seals which in turn burns off at start up causing the smoke.

If it isn't using any oil, then I wouldn't worry.

 

its only running a standard v5 sti turbo a vf28 i think,pushing 335/400 at 1 bar i was told,im gonna do an oil change tomorrow and keep a close eye on it over the next couple of weeks.

 

why have a lump built to take UP TO 800 BHP then bolt a standard vf28 on it,bit overkill is it not or is that a temporary setup mate ?

 

Puff of blue smoke on startup is normal on a stroker had it occasionally on my old 2.1 Type R, slight piston slap on startup is also normal on forged flat fours

 

i only brought it a week or so ago but ive noticed the smoke on start up after i got it hence the reason for this thread.i am planning on putting a bigger turbo and 6 speed if it turns out to be ok but wanted to make sure before any more mods.it was set up like that for running it in and has not been changed since.

 

The noise is probably due to the extra piston to cylinder wall clearance you get with some stroker kits and forged piston installs. Equally they can sound like piston slap untill warmed up.

As has been said, a little bit of smoke on startup isn't a problem so long as it goes pretty quickly and certainly when it's warmed up. If the smoke is really excessive though on cold startup it could be valve stem oil seals or worn rings or perhaps something else more serious.

If you're really concerned about it get a mechanic to have a look down the bores with a borescope and do a compression and leak down test at the same time.

I have to say though a 2.7L bottom end sounds sweet. I bet it's really torquey

 

Has it even been mapped? I enquired about the car you have bought & in the end i decided to leave it as the guy was talking a load of pants.

 

yes it has been mapped ive got a print out and receipt i also phoned mapper to confirm it,the guy was a bit of an idiot tbh and i didnt really believe a lot of what he was saying but because of the lump it had in it and it seemed ok i had to get it,the smoke goes almost straight away its just on the initial start up a puff of smoke comes out and its a bit noisy but when it warms up and is ok,i dont think its burning oil but havent had it long enough to be 100% sure.it is really torquey and im sure with a big turbo will be awesome i just hope its ok.i think compression/leak test is the best solution for peace of mind.thanks for all the replys.

 

if it is worn rings or stem seals is it something i can let wear out and replace when they give up or are they likely to cause damage to other things?sorry for all the questions but i dont have much of a clue on these things.

 

Valve stem oil seals.guides will over time get worse and you end up seeing more and more smoke at startup, even when warm and eventually it will smoke all the time but it won't neccessarily kill the engine. However warn piston rings will end up eventually either scoring your cylinders or potentially breaking and doing some very expensive damage to other engine internals like your pistons and exhaust valves as well as the cylinder bores/linders, oil pump, crank and bearings if you get piston ring bits in the engine.

It's probably none of that and just how the engine runs normally. For what it costs a visit to a good mechanic/Subaru specialist will give you some inexpensive peace of mind.

 

If you really want to be certain just do a compression test. Im sure it doesnt cost much. I use to get a puff of smoke on previous Impreza & most forged engines sound abit noisy.

Hope this helps

 

had a compression test,everything seems ok.thanks for the advise everyone.