Hi:

One of my mates, who have a Legacy RS, had blown his engine. After a couple of minutes of hard driving (about 200 km/h in fifth gear with 20 psi of boost, a looong straight road of course :-) the engine begun with a little "clank clank" sound.

The car was turned off and was stopped a for some hours. Later it was drived in a normal fashion until the suddenly engine turned off feeling "stuck".

Well, finally one conrod bearing was melted and the conrod damaged too. This is not the first time that I know a similar failure, so

Why this could Happened? Stress?, Lubrication problem?, Both?

Any idea?

Regards from Chile

 

pardon the first post, but isnt 20psi's a little too high ?

[Edited by prana - 11/28/2003 4:45:28 PM]

 

That seems like a very high boost figure. It was probably detting its **** off, hence the blow-up.

 

It probably would be a good idea if you listed any modifications the car has. 20psig on a standard engine is too much IMHO.

Cheers

 

You're right, sorry, here I go:

Legacy/Liberty RS MY93

Engine: EJ20G Open deck

Mods:

- 3" Exhaust and Banzai muffler
- HKS Super mega flow Air filter
- MRT Fuel Cut defender
- Walbro 255 lts/h Fuel Pump
- Aeromotive Fuel Pressure Regulator
- IHI VF22 Turbo
- S-AFC
- Greddy Profec B boost controller setted to 20 psig in high mode, 15 in low

More facts:

This car wasn't driving at 20 psi everytime, just at "special" events only.

The AF gauge always show the last green led when the car was in WOT (I think the car was always overfueled)

Beside, when the engine was opened, the pistons were in very good conditions, there wasn't any sign of damage.

Ideas?

Regards from Chile

 

So the car has an SAFC (Fuel Controller) but no form of ignition control? ie Re-mapped ECU, Standalone ECU? IMO running this amount of boost with no ignition modifications is a recipe for detonation. Is the car also using the standard intercooler/chargecooler and what Octane fuel was he using?

Cheers

 

As above, E.G temps would be through the roof, heat soak down the rod destroying the oil film around the bearing and/or det shearing the oil film.

 

Hi:

Well, here in Chile, there isn't any real tuner, so the only "kind" of electroning tuning is by using S-AFC and AVC-R... neither nobody have a Wide band Oxygen sensor or a something as a Knock link.

We're not as lucky as another places. At the other hand, the maximum RON value is 97 which and always was used for this car.

Also we never heard any detonation, but we never measure the EGT. By the way, Does anyone knows what are the tolerable values for EGT's?

Regards from Chile