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[familyman]

I've sorted cooling fans running on for a long after switching off, fitted new dermofat and problem gone, so now i want to play with the engine a bit,
I've read about  fitting 3.0 mv6 cams to a 2.5 which sounds intresting only concern is that are they a sraight swop ie no machining etc.. also i have early the type auto box (non adaptive) will altering the valve timing etc alter the way the auto box behaves too much (tech guys now what i mean), has anyone done this swop to an early 2.5 auto.
Any feedback welcome cheers all

[TheBoy]

You box is still adaptive, just not software updatable.

The cams are a direct fit.

[Kevin Wood]

Bear in mind you will need to change the cam cover gaskets and will need some sealant for those, It's advisable to change the camshaft oil seals and the cam belt will have to come off so if it's anywhere due a change it may as well be done, including the tensioner pulleys. Ditto the aux. belt and water pump. It's a good time to do the spark plugs too, if they are ready for a change!

You'll need a cam belt locking kit.

It's not a difficult job but you need to set aside planty of time and be fairly methodical about how you work in terms of getting the cams timed correctly, not mixing up the cam bearing caps and avoiding valve to piston contact while you're assembling it again.

Kevin

[familyman]

Cheers sounds easy enough.Looks easy too.   What sort of power gains do you think. More torque or just more horses, or both. Cheers TB  still geting used to these boxes. Okay to drop  cams straight onto old lifters?

[Kevin Wood]

Okay to drop  cams straight onto old lifters?

The consensus is that this is Ok provided they are both in good condition.

If you have any lifters which are a little noisy or take a while to quieten after startup this is a good opportunity to get them out and clean them. There's a howto for this on this site.

Expect the lifters to be noisy on initial startup after the cam change as they pump up and adjust to the new cam profile. Drive it gently until they quieten, which can take a while.

Kevin

[familyman]

Cheers Kevin. car quiet on start up (not bad for 145000 miles) no undue cam noises. Always use an oil purge/flush when changing oil so engine fairly clean inside. found that out when i done the cam cover gaskets and cleaned breathers out, so they should be okay
Job for august hols then, I'll keep you posted and how engine feels after. Now just got start assembling all the bits.
Any other worthwhile power mods short of buying a 3.0. What about plugs, platinum double coppers or just standard. Don't want an induction kit but any one used direct replacement k&n in standard air box etc.......

[Kevin Wood]

I doubt plugs will gain you anything. My theory is that they're either giving a good enough spark to light the mixture, and the engine runs, or they're not, and it misfires

Platinum plugs and the like are really just to extend service intervals as they last longer.

The standard Vauxhall plugs are good quality 2 electrode (or 4 in later ones) and not too dear.

Induction kits aren't reckoned to do much other than increase noise and there's a real risk of increasing the intake air temperature if you ditch the airbox. A a K&N panel in the airbox might be worth a try but go easy on the filter oil because if oil mist gets into the MAF sensor it'll get the hump. Induction isn't the main restriction in these engines. The exhaust manifold design is pretty pants and this is probably the first thing to address. Not too many options to change that unfortunately.

Cheers,

Kevin

[nemesis_v6]

has anyone changed the mannys on there omega could they post it for me thanks jody

[Marks DTM Calib]

I personaly would never fit 4 electrode plugs (not even to the ones Vx say to fit them to), they again only realy offer an extended service life and often the plugs can work loose before the change interval anyway....

I also feel that the extra electrodes can shield the spark to an extent............

[Martin_1962]

I personaly would never fit 4 electrode plugs (not even to the ones Vx say to fit them to), they again only realy offer an extended service life and often the plugs can work loose before the change interval anyway....

I also feel that the extra electrodes can shield the spark to an extent............

I have heard about the shielded spark too - supposed to be bad for LPG equipped cars

[familyman]

just another question on the cams. If i buy 2nd hand are there any identification marks for mv6 cams or part no's stamped to confirm. Don't want to just buy another set of standard cams. Can any one recomend a good exhaust system , from cats back( don't want to decat) and i don't want to end up with a drainpipe out the back.
Showing my age now but we always used to use Piper systems, Janspeed to expensive then. For the sensible people brakes are improved have fitted new Vx discs front and rear and EBC green stuff pads, replaced brake fluid with super dot4 and am looking for some aeroquip hoses. New springs front and rear 20% uprated but standard ride height.
Cheers all