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[GrahamT]

Has anyone converted their 2.5 manual to 3.0?

If so was it worth it and did the 2.5 gearbox survive?

Thanks

[henryd]

Easy swap as plug and play but AR25 gearbox will not cope with 3.0 torque

[tigers_gonads]

How many miles has the manual box done ?

I ran a 3ltr with a R25 box with no problems but it was a relatively low millage box with only 90K on it.


With the R28's liable to have plenty of miles on by now / in short supply and the R30 like rocking horse shite, i'd just do it and enjoy 

[Kevin Wood]

Yep, the manual 2.5 gearboxes are no problem with a bit more power. It's the automatic gearboxes that are an issue.

You might want to consider a diff with a taller ratio, though, but you can see how it goes with your current diff first.

[GrahamT]

Thanks guys.

A few more questions. Finding a x30xe from an auto doesn't seem to be a problem. But will my 2.5 flywheel fit and will an auto ecu be happy running a manual?

[tigers_gonads]

Thanks guys.

A few more questions. Finding a x30xe from an auto doesn't seem to be a problem. But will my 2.5 flywheel fit and will an auto ecu be happy running a manual?

IIRC if its a auto ecu with a manual box, you need to ground a wire to earth  or the engine wont run 
If you do a search on here, you should find it 

As for the R25 gearbox with the auto's (3.91) diff, you will find that the revs will be about 200 rpm higher at 70 mph ish so depends on how deaf you are or how much motorway driving you do tbh.

I run a 3.2 / R28 box with the auto's diff and it gets off the line very well  .

Pros are you can stick it in 5th at 30mph and it will pull away with ease.
Cons are 1st is too low BUT i've a lpg tank in the back and occasionally pull a pikey van so that 1st really helps getting out of junctions quickly 

[henryd]

Easy swap as plug and play but AR25 gearbox will not cope with 3.0 torque

If I had read the post properly I would have read the manual bit

[GrahamT]

My car is already a manual and as far as I can tell has the same diff ratio as the 3L.

I have actually contemplated putting in the auto diff to get a bit more acceleration.

As right now it sits at about 2800rpm at 70mph.

Thanks

[Migv6 le Frog Fan]

From memory - the flywheels are interchangeable, but the spigot bearing on the end of the crank will need swapping for your manual one.

[tigers_gonads]

From memory - the flywheels are interchangeable, but the spigot bearing on the end of the crank will need swapping for your manual one.

Yup 
Also the 3ltr engine will also run okay on a 2.5 manual engine ecu abit very slightly down on power due to the slightly reduced fueling right at he top end 

[GrahamT]

From memory - the flywheels are interchangeable, but the spigot bearing on the end of the crank will need swapping for your manual one.

Yup 
Also the 3ltr engine will also run okay on a 2.5 manual engine ecu abit very slightly down on power due to the slightly reduced fueling right at he top end 

That's good. So I can swap the engine over while I look for the correct ecu, transponder and chip.

One other question just to make life a little easier. I take it the wiring harness etc for the engine management is the same for the X25XE and the X30xe?

Thanks

[Migv6 le Frog Fan]

Im sure it will be the same. 3.0 ECU etc. shouldn't be difficult to find. Not many people will be looking for one either so I wouldn't pay too much money for one. 

Edit. One here for £20. 
https://www.ebay.co.uk/itm/VAUXHALL-OMEGA-1994-9-3-0-V6-COMPLETE-ECU-UNIT-IGNITION-MODUAL-1-KEY-CHIPS-AF-/332552551874

[tigers_gonads]

From memory - the flywheels are interchangeable, but the spigot bearing on the end of the crank will need swapping for your manual one.

Yup 
Also the 3ltr engine will also run okay on a 2.5 manual engine ecu abit very slightly down on power due to the slightly reduced fueling right at he top end 

That's good. So I can swap the engine over while I look for the correct ecu, transponder and chip.

One other question just to make life a little easier. I take it the wiring harness etc for the engine management is the same for the X25XE and the X30xe?

Thanks

When I dropped a 3ltr lump into my 2.5, All I needed was the bearing because the 3ltr lump came off a auto 
Forget about the shorting wire bit 
That was for a auto engine ecu 

Also iirc, the 2.5 manual diff is a 3.7 so again just bolt together then go and play 

[GrahamT]

To find a decent engine now.

Thanks for all the advice. I have a week off work in nine weeks. Enough time to find engine clutch spigot bearing etc.

Thanks again.

[Migv6 le Frog Fan]

To find a decent engine now.

Thanks for all the advice. I have a week off work in nine weeks. Enough time to find engine clutch spigot bearing etc.

Thanks again.

Here ya go.  http://www.omegaowners.com/forum/index.php?topic=142594.0