dooby-do

iTrader: (2)

has anybody on here had a ground crank im supposed to be buying a rebuilt engine but the the cranks has been ground,the crank was ground and new acl race series 0.25mm bearings fitted,i have heard that its not good for subarus to have a ground crank so wanted to see if anybody has had this done to there crank,and if its going to cause me any issues,also this is the first time it has had the crank ground so was told the first time is ok

DJ_Jon

iTrader: (7)

Cranks can be reground, but its utterly pointless & not cost effective. I predict a post very soon saying my engine is f*cked....

Buy a new one & save your self a lot of ballache.

BBB3

iTrader: (7)

it would put me off buying,

seems a bit of a short cut if you're building a engine and you putting all new acl bearing etc...then get the crank reground ? you would want it to last after all the hassle of building it...because it might be expensive but save you in the long run...

WildPikey

I've not had any experience with the Subaru Crank shaft but have had and seen plenty of other makes done over the years without any problems, I think normally the only reason it doesn't get done is because Subaru's seem to do a proper job on the crank and completely knacker it to the point where it is no longer useable, Yours obviously was re-usable and I wouldn't worry about it personally, The last crank I had re-ground was 2 years ago, An old Truck with a 14 litre cummins engine with over 400bhp, Its in use 20 hours of everyday pulling up to 80 tons at any one time and is still going strong

DJ_Jon

iTrader: (7)

I really wouldn't use a re-ground crank on a Subaru, you are asking for trouble. they are not like cranks in other cars. When re-ground they need to be re-hardened & than they need to be straightened & balanced. By the time that is all done its the same cost as a brand spanking new crank & you have no worries with a new one.

Other cars, yes, Subaru, NO!

Ask many of the reputable engine builders, such as API or Enginetuner - I guarantee you will get the same response.

BBB3

iTrader: (7)

a 14 litre 400bhp truck which pulls 80 tons crank is probaly bit different do a subaru crank

end of the day its up to you bubby if you are in doubt go with your feeling....

dooby-do

iTrader: (2)

ok the engine is 95 type ra engine almost ready, it has been built on a version 4 sti bootom all fresh with new acl etc etc and genuine sti forged pistons, then the 95 rs heads on but with sti 4 cams fitted.then i asked if the crank had been polished or ground and was told the crank was ground and new acl race series 0.25mm bearings fitted and was told they are perfectly fine to be used at first grind without any problems at all.the engine was not built for me but built for one of his own cars but he would sell the engine and build another.really nice bloke but just want to make sure i wont have problems 10k down the road as i was hoping to push around 350ish throught it

WildPikey

My point was it had been re-ground and gets a very hard life and is still going strong, Normally Saying you need a new crank if it's within tolerances is like saying you can't have your head skimmed if the head gasket fails Ok sometimes you can't but more often than not a re-grind on the crank is all that's needed where as when a head gasket fails it may just need a light skim With that in mind I have no experience of re-grinding a Subaru crank but if they are not good enough to be re-ground within tolerences then they were not very good in the first place imho

WildPikey

https://www.scoobynet.com/general-te...nd.htmlhttp://

Read the last post

dooby-do

iTrader: (2)

https://www.scoobynet.com/general-te...-re-grind.html
read the last post its kind of a mixed subject on the matter.the main issue is i just dont want to fit the engine for it to give up on me so thought i would ask some people who actually new a little more about it than me

MOTORS S GT

iTrader: (2)

The main problem is you can't remove the ball bearing bung in the drilled oil gallery, therefore there is a small section off gallery that is a dead end, & deposits off metal from the bearing failure & grinding procedure cannott be succesfully removed.

WildPikey

That man is a well respected engine builder, He knows what he is talking about where as I am just saying what I have heard/been told regarding Subaru's so I'm out lol

alcazar

iTrader: (2)

As above, if Harvey says it's OK, then it almost certainly is.

dooby-do

iTrader: (2)

i have heard a lot of good things about harvery and surely if he is doing them on some of his own builds it cant be as bad as it sounds

TheVoices

iTrader: (5)

Subaru themselves sell over and undersize bearings, the dealer technical manual (for the bugeye WRX at least) lists the part numbers.

The manual also details the procedure to check the crankshaft and states that if it is outside the tolerances shown, a regrind will be required.

I take this to mean that it is possible if done correctly ?

DJ_Jon

iTrader: (7)

Just about anything is possible, doesn't mean to say its a good idea. Take sticking your **** in a blender, it is most definitely possible, but not recommended....

TheVoices

iTrader: (5)

Yes, but I don't think the manufacturer of your c**k lists the procedure in their technical manual ?

prodriverules

iTrader: (52)

+1
I wouldn't hesitate to do mine if needed tbho,i personally know of 2 that have had regrinds with no issue's!

BBB3

iTrader: (7)

i know what you ment mate

DJ_Jon

iTrader: (7)

Hey, it's your money & your engine. If David at API thinks it is a bad idea then that's good enough for me.

legacydan

Give steve @ SMG a call or Stewart @ TFS racing or Dan @ Surrey Subaru Specialists

All of the above will say no to regrinding due to the ball bearing @ not being able to clean out the oil ways. New crank or a polish everytime. You don't want to end up pulling the engine out again.

WildPikey

But this could easily be avoided could it not? Use a decent engineer as said and job done Opinions are not fact! It can be done and can be done properly despite the horror stories

MartynJ

No regrinds on Subarus for us either and we carry out all our own engineering in house.

jayallen

iTrader: (31)

How does that work....

Is it a 95' RA CDB or a V4 STI ODB?

dooby-do

iTrader: (2)

i belive a ra block with sti pistons crank rods ect,i spoke to a company down here that do crank reginds,they are not the company that done the crank and they said they would do a subaru crank for a very minimum grind,to be hounst its sort of a mixed situation on the crank ground situation like harvery said he has had 1 in his sti running 400ish bhp with no issues at all soo it can be done,im gathering companys just dont like doing it were as some will,same as surely if its state in the subaru manual it must be able to be ground i dont doubt that a massive ground crank would cause issues but a lightly ground 1 well thats another situation

legacydan

SMG is one of the top engineers for subarus & I would trust every word he says, if he won't re grind a crank then it's not worth doing.

leedscal

iTrader: (2)

I just sent my crank of for regrounding and have sent many cars
vans and truck cranks off with no come back, they take the smallest amount if you dont even notce , 0.25mm will not weaken it and wont cause any hassle or noise as they put bigger bearings on to suit, i wouldnt worry bud just make sure its ,been built up right.

APIDavid

iTrader: (4)

Confirming here, Cranks on a Subaru engine can be ground, there is no engineering reason why not. But as said before, the Subaru crank has blind ended oil galleries and ball bearings bashed in the seal the galleries, rather than grub screws.

If the ball bearings are removed and the crank thoroughly cleaned out, it ought to be fine. However, removing the ball bearings can only be done by spark erosion which is expensive to do. And once the regrind is done, the spark eroding is done and the ***** replaced, you will so close to the value of a new crank, that it makes a nonsense of doing it the ' cheap ' way.

We would never grind a crank unless it was a very expensive steel one, which would have grub screws in anyway.

An engine with a standard type reground crank is not recommended by us at API.

David