after having my car checked over today, due to a rattle on startup was told my bearings seem to be the problem
so going to rebuild it with some acl ones, question is i might aswell forge the engine whilst stripped but not chasing huge bhp as happy with the 310bhp i have now so dont wont to spend a small fortune on doing it,

any ideas on wot route to take to toughen up the engine but not go ott and rough cost of price ?

was told ver3sti pistons are forged is this correct as can get a set for under £30 ?

forgot to mention i have a CDB if that makes any difference.

 

Howsey, go for a 2.1 stroker,you know you want to lol!!

 

i did say, not ott

 

If it's done the bearings, and I assume you mean big end? then you need to budget for a new crank, new oil pump and modine.

You also need to ensure that the sump, blocks, heads and oil pump if you re-use it, but just uprate it, are THOROUGHLY cleaned to ensure that no swarf from the bearings remains to do dmage to your rebuild.

As for pistons, not sure. Mine has Manley and their rods, plus ACL race bearings

 

do you only get the rattle on startup? if so check your heat shield, its a heck of a lot cheaper to fix

 

also not a sticky tappet?

 

I am in the same boat as you with regards to 'what should I put in the engine since its going to need rebuilt anyway?'.

I have just gone the full hog and bought pistons, rods and studs.

The pistons were £400, rods £350 and the studs were £80. On top of that I have replaced the big end bearings at a cost of £90.

Once it has all been put back together I will have a fully forged engine ripe for the M321T I am in the process of ordering and I know it will be able to take power levels of 450+bhp happily without me worrying.

I was originally just going to fit new pistons but why stop there when the engine is in bits and everything else is accessible?

 

To be diagnosed as potentially bearings, one must assume the noise goes as soon as the oil pressure light goes out as the bearings recieve pressurised oil? Another possibility is that you may get some piston slap as the stone cold engine accelerates from zero to 1500rpm on start-up then quietens somewhat as the engine settles at that rpm.

JohnD

 

Ha,ha! you'll still worry!

JohnD

 

True.

I should have said "I wont worry AS MUCH"

 

Steve - who diagnosed as bearings ?

Or is it just from a forum post from you saying it rattles on start up ?

Could be a million things from heat shield to cam belt idler (were these replaced on the recent cam belt change ?) to xyz number of other things.

 

you have a 1993 wrx so you might have the forged pistons which can slap when cold.
i have the same car and mine knocks its bag off till its warm. its been confirmed on here with photos that some early wrxs had forged pistons.

 

it is rattling under load aswell now, as for start up could be the problem as when i start engine it goes to about 2500rpm till warm,
but has done this since ecu fitted duncan you can tell me if this is normal on a simtec? or possibly idle control valve
,heat sheilds have been removed and all pulleys where replaced on cam belt change, oil changed recently to millers and plugs changed aswell, just changed up pipe so can rule that out as double checked sheild before fitting.

 

if i was suffering from this would it not be detected it on the simtec ?

 

Nope.

Knocking (from pistons etc) and Det are different things Steve.

 

Going to 2500rpm can't be right!
If it's rattling under load when warm, I would say it's sounding more likely to be bearings although I thought they might be more audible on the overrun?



Nope.

Knocking (from pistons etc) and Det are different things Steve.

How close are the sound frequencies of det and slap? I'm sure a device such as the KS3 would "hear" slap and display it, so would an ECU react to it?

JohnD

 

Very different sounds John. The frequency must be miles apart.

Steve - yeah that isnt right re the cold start - never seen it do that. Will sort for you

 

Aye?!?!? You've got me all excited now... time to do a search

 

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