Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: countrywoman on 03 December 2022, 16:27:42

Title: cylinder head
Post by: countrywoman on 03 December 2022, 16:27:42
After getting the head I bought refaced I went to fit it (x30xe) and found the deck height to intake was a lot bigger than the old heads. Ended up robbing the intake valve out to go in the old head. Now this engine is ex plod so would it have been modified to a higher compression? If it has had them both refaced then they took loads off or is there a low compression version
Title: Re: cylinder head
Post by: Doctor Gollum on 03 December 2022, 19:04:15
It's not the correct head for that block.

There are differences between the four V6 head options.
Title: Re: cylinder head
Post by: Doctor Gollum on 03 December 2022, 19:17:38
You could fit the heads from a 3.0/3.2 to a 2.5/2.6 respectively to give better breathing under load, but only if you fitted a pair of heads and the matching breather bridge as they aren't interchangeable.

Either your engine isn't a 3.0 or your new head is wrong.

Electrically, the 2.5/3.0 are identical, as are the 2.6/3.2 and yours wouldn't be the first Omega with a replacement engine that was misrepresented by the seller... Especially as the 2.5 is architecturally related to the C25XE. There were more Vectra 2.5s than 3.0 Omegas.
Title: Re: cylinder head
Post by: countrywoman on 03 December 2022, 21:16:37
It looks identical just has more meat on the face by a good mm, not bothered at least the valves fit. Now just need 2 guides replacing in the other head.
Title: Re: cylinder head
Post by: Doctor Gollum on 04 December 2022, 00:25:21

They might look the same at a glance, but that you can see the difference on the head tells you it isn't right :-X

You will be bothered when the inlet divider breaks as you tighten it down and/or doesn't seal.

Shame to do all that work only to bodge the crap out of the thing that makes it move.
Title: Re: cylinder head
Post by: countrywoman on 04 December 2022, 11:53:42
No bodging, the 2 OG heads going back on so it worked out okay. Just need to get the 2 split valve guides renewed.
Title: Re: cylinder head
Post by: Migv6 le Frog Fan on 04 December 2022, 12:45:52
Im 99% sure engines in plod cars were big standard.
Title: Re: cylinder head
Post by: countrywoman on 04 December 2022, 14:31:08
Apart from the chipped ECU apparently.
Title: Re: cylinder head
Post by: Migv6 le Frog Fan on 04 December 2022, 16:19:39
That should have said big, not big.  :-[ ;D
Cant remember chipped ECU,s being a thing, but my memory is piss poor.
Title: Re: cylinder head
Post by: Doctor Gollum on 04 December 2022, 16:56:47
Apart from the chipped ECU apparently.
The 3.0 could be chipped, but not likely to have been as a matter of routine. Some forces did for certain applications, but you have more chance of finding a rust free ega with ten miles on it for a fiver.
Title: Re: cylinder head
Post by: Doctor Gollum on 04 December 2022, 16:57:52
No bodging, the 2 OG heads going back on so it worked out okay. Just need to get the 2 split valve guides renewed.
Waste of time having that one refurbished then.
Title: Re: cylinder head
Post by: biggriffin on 04 December 2022, 19:33:29
Apart from the chipped ECU apparently.
The 3.0 could be chipped, but not likely to have been as a matter of routine. Some forces did for certain applications, but you have more chance of finding a rust free ega with ten miles on it for a fiver.
.

  Some 3.0L were "modified" or chipped as the you'ff say, I had a chip from an ex-diplomatic protection car, slightly better fueling, some NIPS cars had larger throttle bodies and a modified map. I think the chip I had is still around Hoof'land. But l haven't asked if the person still has it.
Title: Re: cylinder head
Post by: countrywoman on 04 December 2022, 22:36:40
There's a label on the ECU saying its been overhauled so might be chipped.
Title: Re: cylinder head
Post by: biggriffin on 05 December 2022, 19:58:48
There's a label on the ECU saying its been overhauled so might be chipped.

 Common sticker, on factory refurbished units.
Title: Re: cylinder head
Post by: Doctor Gollum on 05 December 2022, 20:40:10
There's a label on the ECU saying its been overhauled so might be chipped.
It’s probably from a 2.5 ;D
Title: Re: cylinder head
Post by: countrywoman on 08 December 2022, 16:07:44
update, £20 to have 2 guides replaced and the new intake valves turned up. Now I have to wait till its warmer to go to my workshop!!!
Title: Re: cylinder head
Post by: Migv6 le Frog Fan on 09 December 2022, 16:38:18
Wassamatterwifya ? Im 63 with a fooked skeleton, and have just come in from working on the drive all afternoon.  ;D  :D
Title: Re: cylinder head
Post by: countrywoman on 09 December 2022, 19:56:58
I'm 67 and have always felt the cold.
Title: Re: cylinder head
Post by: cam.in.head on 10 December 2022, 21:44:59
me too!
at school i was nicknamed "hypo" cos i turned purple playing sports outside in winter.
got me out of doing it afew times thou so all good.
Title: Re: cylinder head
Post by: Migv6 le Frog Fan on 10 December 2022, 23:07:41
I worked outside for years, so was pretty good with the cold, but Ive got softer and older now and feel it more.
I just try and wrap up warm, and keep moving as quickly as possible.
Doing front discs & pads on the Omega tomorrow for the MOT Monday. Hopefully that will be it until Winter is over.
Title: Re: cylinder head
Post by: johnnydog on 11 December 2022, 10:05:23
I don't particularly enjoy working outside on the car this time of year, especially when it's down to near freezing temperatures. Keeping my core warm isn't the problem - it's preventing your finger ends from dropping off from the cold and being unable to feel the ends of your fingers to do the job in question. Appropriate work gloves don't help much, if at all...
Roll on Springtime ....
Title: Re: cylinder head
Post by: countrywoman on 11 December 2022, 10:23:22
Fitted the new coil/module to mum's car yesterday, my hands hurt and it was only 2 nuts and bolts. Snow today so not looking at it till it clears as it still wont start, needs a new starter. 
Title: Re: cylinder head
Post by: JamesV6CDX on 13 December 2022, 01:42:23
Ooops duplicate post, created in error!
Title: Re: cylinder head
Post by: JamesV6CDX on 13 December 2022, 01:42:44
Absolutely with you on this, I fitted a replacement battery to my neighbors Shogun yesterday after she failed to start, my fingers were like ice afterwards!

There was a time I'd have been rebuilding Omega engines in that.... but now, I'll just throw another log on the fire and wait for a better day! (Especially when I have to get under it!)