Kai4130

Have a 1995 WRX engine in my VW, after changing the cambelt and checking the timing marks several times before fire, I ran the car which appeared to run well with no exhaust after the turbo. Anyway engines running, hear LOUD metal snapping sound and the engine cuts out. Check the timing again and the right bank exhaust cam is probably 4-6 teeth out (advanced forward) and the cam is STIFF to move and will only move with the aid of a rachet.

So with a second thought it's obvious ive bent a valve or something. Inlet cam is as expected and easy to move. The exhaust cam is stiff and reluctant move throughout its entire rotation (360). What's weird is that with the cam lobes up the cam should be under minimal load from the valve springs and easy to rotate.

My theory is that either one of the exhaust valves has snapped/bent or the cam has bent.

I've pulled off the exhaust manifold and can see that each of the exhaust valves are still functioning as expected, all be it Im uncertain if any are bent.

Regardless something's not right and I've absolutely no idea whats restricting the cam from rotating.



Anyhow..... The solution.... Possibly. I'll need to remove the suspect head and get it checked out.

I've two engines now. Both a CDB EJ20 and I'm lead to believe they are both 1995 WRX engines. I know they have both been fitted into 1995 WRX JDM cars as neither engine has the PCV which I'm believe is a JDM thing. Regardless nothing is certain about the engines except they are both EJ20 turbo engines and both have run a TD05 turbo.

I'm adamant that the engine fitted into my VW will require a new head on one side as the best fix to my stiff cam problem.

So I've removed the head off my spare engine and disassembled it ready to go into the car. I've started to remove the head fitted to the engine in the vehicle. First thing I've noticed is that the cams have different numbers stamped into them.

The engine in the car has the exhaust cam stamped with L3EX, oh this has the Bakelite cam wheels






The engine on the bench, the exhaust cams are stamped L2EX and is fitted with metal cam wheels





Question: is it common whilst damaging/bending a valve is it possibly/common to bend or damage the cam?

Also are these cams the same to one another? With just different castings stamped into them.

I'm assuming the head castings are the same and will be interchangeable.


I've tried searching but to no avail into whether the cams between the WRX and UK 2000 are the same or not. As I'm uncertain what my engines are and with the possibility of interchanging parts.



So my solutions.

I'll fit the head from the bench engine onto the engine in the vehicle. Being concerned about the suspect cam currently in the vehicle I will check (once I've got it out) if it straight and if it rotates freely in the bench head. My worst case scenarios is if the cans bent.

Would I get away with just fitting the straight exhaust cam from the bench engine as they are all possibly the same? Or if I start changing cams should I fit all four cams from the bench engine into the engine in the vehicle engine


I know you all love a picture

Kai4130

Ok just to clarify,

Does anybody know what these cams are?

Are both sets the same just different years possibly?

If not which would be the more aggressive set to go for?

Kai4130

Interestingly enough according to this thread I have two sets of UK cams.

https://www.scoobynet.com/scoobynet-...sti-heads.html

Kai4130

So managed to get the cams out tonight and the cam lobe heights between both sets all measure up the same so they are all interchangeable.

Thanks Merlin for your input on identifing what parts I've got at hand.

Turns out the stiff cam is due to a dry bearing, with the head removed there is no eveidence of damage to the valve train by contact with the piston. I still cant understand how the cam was so many teeth out.

The suspect bearing