36 replies to this topic

[fezzasus]

so I had a quick look under the rocker cover today...



so, what's the best engine I can source to drop in. Specifically i'm wondering what modifications I need to make to a B207 engine to make it think it's a Z22se

[CocoPops]

Vocky!

[jules_s]

So for future reference for a numpty like me (and i've not seen any other posts by the OP) What's the issue there....apart from the seemingly obvious?

[techieboy]

Best engine to "drop" in would be another Z22SE. B207 will need the 7-1 crank from a Z22SE (for the trigger wheel pattern and the bolt pattern for the Z22SE flywheel), some accessory holes on the head blanking off, Z22YH(?) coil pack for the different style of spark plug, oil cooler return changing. May be a question mark over the Saab cams in an NA setup. The Aero cams, though from a boosted car, didn't work with my Z22SE head, though that may have been down to timing differences between the engines. Think I've still got a couple of pairs of NA cams in the garage, if they're of any use?

[fezzasus]

'jules_s', on 13 Apr 2012 - 9:17 PM, said:

So for future reference for a numpty like me (and i've not seen any other posts by the OP)

What's the issue there....apart from the seemingly obvious?

There's pretty bad cam wear.

All the inlet cams are pretty worn, with most of the hardening removed - all cams show linear wear scares suggesting some entrainment of abrasive matterials and three cams showed pitting, including the one in the photo.

The fact that this engine has an oil leak around the cam cover and that there's rust on the cams makes me think that it's because of oil starvation.

[fezzasus]

'techieboy', on 13 Apr 2012 - 9:18 PM, said:

Best engine to "drop" in would be another Z22SE.

B207 will need the 7-1 crank from a Z22SE (for the trigger wheel pattern and the bolt pattern for the Z22SE flywheel), some accessory holes on the head blanking off, Z22YH(?) coil pack for the different style of spark plug, oil cooler return changing. May be a question mark over the Saab cams in an NA setup. The Aero cams, though from a boosted car, didn't work with my Z22SE head, though that may have been down to timing differences between the engines.

Think I've still got a couple of pairs of NA cams in the garage, if they're of any use?

This does tie in somewhat with an upgrade plan though - just forces my hand a little, so if I can put anything in that takes longer to prepare (given that the engine is still working and will have some life left in it) but more performance is good by me.

The cams could be useful though, i'll have to investigate tappet cost to see if it's an option for me, i'd prefer to change them while i'm at it.

[fezzasus]

more wear:

[techieboy]

'fezzasus', on 13 Apr 2012 - 9:33 PM, said:

The cams could be useful though, i'll have to investigate tappet cost to see if it's an option for me, i'd prefer to change them while i'm at it.

Think I may still have a set of those as well left over from the last rebuild.

What are the rockers like? It's not got "uprated" springs in it, has it?

[The Batman]

i dont think they are that bad is there actually a fault?

[fezzasus]

'techieboy', on 13 Apr 2012 - 9:38 PM, said:

'fezzasus', on 13 Apr 2012 - 9:33 PM, said:

The cams could be useful though, i'll have to investigate tappet cost to see if it's an option for me, i'd prefer to change them while i'm at it.

Think I may still have a set of those as well left over from the last rebuild.

What are the rockers like? It's not got "uprated" springs in it, has it?

hmmm, that could be very useful! The engine's completely stock as far as i know.

[fezzasus]

'joe_589', on 13 Apr 2012 - 9:40 PM, said:

i dont think they are that bad is there actually a fault?

Not exactly - I took the rocker cover off this evening because i've had an oil leak from the cam cover and wanted to see exactly where it was coming from - i'm changing the oil tomorrow so it seemed a good time to look.

The photos don't capture it very well but it's one of the worst cams i've seen. The pitting does make me worry because that's implying the hardening has been completely worn from the cam and they are now similar hardnesses - the pitting will continue to happen at greater rates, dumping metal into the oil causing further wear and finally failure. I'd be happy if it wasn't for that, but 3 of the inlet cams are showing pitting.

[alanoo]

What kind of mileage ? It's cam wear yes, roller followers to not completely remove cam wear unfortunately, but if we're speaking of a 100k+ engine, looks perfectly normal to me...

[fezzasus]

'alanoo', on 13 Apr 2012 - 9:46 PM, said:

What kind of mileage ?

It's cam wear yes, roller followers to not completely remove cam wear unfortunately, but if we're speaking of a 100k+ engine, looks perfectly normal to me...

Just ticked over 70 k, although i've only had it for the last 15 k - i've got service history but that doesn't show how regularly it was driven or how it was driven.

[fezzasus]

this shows the pitting better:

[jules_s]

'joe_589', on 13 Apr 2012 - 9:40 PM, said:

i dont think they are that bad is there actually a fault?

Knowing jack squat about failures i thought the same.

I sort of thought the narrowing of the cam was the issue; not some scoring on something that goes up/down circa 100 times a second

Why would that shag the whole engine anyways?

Meh, I'll learn about engines one day

[The Batman]

I defiantly wouldn't change an engine because of that! I reckon he is looking for an excuse to dump a b207 in Although be warned its not straight forward

[fezzasus]

'jules_s', on 13 Apr 2012 - 9:54 PM, said:

'joe_589', on 13 Apr 2012 - 9:40 PM, said:

i dont think they are that bad is there actually a fault?

Knowing jack squat about failures i thought the same.

I sort of thought the narrowing of the cam was the issue; not some scoring on something that goes up/down circa 100 times a second

Why would that shag the whole engine anyways?

Meh, I'll learn about engines one day

You're right, narrowing of the cam (this can usually been seen comparing the side taper to the taper on the side of the cam tip, they are the same when new, but cam tip wears flat so no taper - this results in a loss of power, but no real engine issues.

The pitting is a mode of failure though - the material that's removed from the cam or tappet circulate around the engine as a 3rd body abrasive, causing liner scoring, further cam/tappet wear, blocking oil channels or the oil pickup, increasing filter pressure. wear metals also act as deposit seeding points which causes piston deposits.

[fezzasus]

'joe_589', on 13 Apr 2012 - 9:59 PM, said:

I defiantly wouldn't change an engine because of that!

I reckon he is looking for an excuse to dump a b207 in

Although be warned its not straight forward

a little - it's not an engine i expect to fail any day, but it's certainly not one i'd like to do another 70 k with. I'd want to be fitting a new engine in no more than 20 k more miles, so i might as well get started!

[Nev]

As others have said, I think thats normal wear for an engine of your milage. If you blue-printed/measured the actual wear from OEM spec I would be surprised if it was more than 0.1 mm, which is trifling really. For example you piston rings will probably accomodate several times that amount of wear without issue.

[JG]

agree with Joe, they will go on for many many more miles.