Hello,

Some of you may remember I purchased a V5 Type R earlier this year and the engine failed shortly afterwards [probably due to the crank regrind]!! I sold the car on again and didn't lose too much money so was pretty happy. See below:

https://www.scoobynet.com/scoobynet-...end-knock.html

Anyway, I still have an Impreza itch to scratch (gluton for punishment?) ... and I've found what I think is a nice UK car with all the bits I want.

However, the engine was replaced using an STI bottom end using a reground crank [spot the similarities!!], however the car has done about 12'000 miles since. What do people think? If it's done this mileage since should it be ok? Or am I asking for trouble?

I understand the main issue with reground cranks is contamination due to bearing debris and grinding swarf/particles not been correctly cleaned?

Any experts want to offer any advice?

Or possibly suggest any nice classics for sale up to about £5k.

 

if your having doubts now then you know what to do....jog on

 

A Re-Ground Crank, if done properly, should be of no issue at all ..... how do you think they are made when new? They are not cast smooth

 

avoid!

 

Once bitten and all that......
In reality I would guess that even if this one you have found is perfect and you buy it, every time you go for a blast at the back of your mind will be "what if?"

£5k is quite a lot of purchase power in the current climate - keep on looking?

 

keep looking

 

was under the impression impreza cranks shouldnt be re-ground as it does away with a coating on the crank itself making it weaker ?? is that right

 

The problem with regrinds in not "just" any issues with cleaning it out (which I may add will affect ANY rebuilt engine, as that is an issue with the builder's workmanship).

But also the fact that the grinding process removes the surface hardening that is applied on the surface of the crank journals. This is not the end of the world, but the journals are now not as resistant to wear.

So yes it will work, and if done well can last many miles. But that is highly dependant on the quality of the rebuild work, plus how the car is driven and treated. BUT either way it will not last as long as a new OEM crank. How long that is will be anyone's guess, 30K miles? 60K miles? More? Less? who knows!

 

The re-ground crank can be heat treated.

Does anyone have a link which states that the OEM CrankPins are Hardened?

 

Subaru cranks are not cast at all Pete!

 

think it states it in the workshop manual

 

Looks like I should give it a miss then!!

Anyone recommend a good Impreza currently for sale?

I want something post 1998 [facelifted exterior/interior] with a good engine rebuild and some tasty modifications [Suspension/brakes/wheels and about 300 reliable BHP] lots of history and all round good condition, UK or very good JDM.

 

I'm guessing Forged then, surely they are not Billet?

 

Forged since the late 1980's if I'm not mistaken

 

Interesting ... the CrankPins will be turned on a Crank Lathe and then Case Hardened?