Omega Owners Forum

Chat Area => General Car Chat => Topic started by: Fraggles Rock on 08 January 2017, 10:44:49

Title: DTi vs Tdi
Post by: Fraggles Rock on 08 January 2017, 10:44:49
Obviously the 2.2 is manual only, and from what I gather, the 2.5 treats the autobox as a service.

Looking around, it would seem although that the BM lump is more robust, the only real weakspot on the 2.2 is the fuel pump... Is there any consistency with regard to fuel pump life expectancy?

There's mention of cars with less than 120K failing, and yet others seem to manage 200+ without issue. Is it enough of a worry to avoid high mileage cars, regardless of price, condition and history?

Basically am considering a project and have seen a few cheapish Omegas around, including a couple of diesels, but know little of them...
Title: Re: DTi vs Tdi
Post by: BazaJT on 08 January 2017, 11:12:00
As I understand it the AR25 as fitted to the 2.5 is good enough unless you chip the motor for the extra power when you'd need the stronger AR35 box,I believe these are a reasonably straightforward swap to do.Can't comment on life expectancy of the fuel pumps[never had a Diesel]but the biggest killer of them seems to be running them dry after servicing work and not bleeding them back up properly as it's the fuel that keeps them cool.If you're good on the spanners then the Omega is not too difficult/expensive to keep running.Plenty of expertise on here to guide/help you through problems.I would say that body condition is critical but then I can't weld!!
Title: Re: DTi vs Tdi
Post by: Fraggles Rock on 08 January 2017, 11:17:28
Same as most cars then lol, the fuel cooling makes sense as it looks like the electronics are integral to the pump...
Title: Re: DTi vs Tdi
Post by: VXL V6 on 08 January 2017, 11:49:00
Never driven a 2.5TD so can't make a comment on them, however, I've had two DTi's.

The DTi estate I had was always a bit lacklustre in it's performance, never really got to the bottom of it but other than that it never had any engine / fuel pump issues aside from auxbelt tensioner failure which eventually rips the crank pulley (harmonic damper arrangement) apart. That car went on to do several thousand more miles with the next owner.

The other DTI (saloon) I had seemed to have far more 'go' and would leave the estate for dead. Did quite a bit of work on it to bring it up to a reasonable standard but at 161K the fuel pump, or rather the EDC on top of the fuel pump started to play up. The EDC is a circuit board encased in a gel and requires specialist equipment to repair, at the time I was looking at around £1000 to get it fixed which didn't seem viable on a car that was beginning to rust around the rear and I didn't really consider it worth investing that sort of money in.

More recently the price of the EDC repairs have dropped considerably and if the car is purely a project it's probably not a problem, it's just if you decide to sell an old car like an Omega you'll never get even close to recovering your money.
Title: Re: DTi vs Tdi
Post by: TheBoy on 08 January 2017, 14:33:51
Firstly, there was never a Tdi Omega.  The diesel choices are:

2.5TD - BMW engine, as used in P38 Range Rovers of the era, and the 525tds. Heavily detuned in the Omega. Available in manual and auto form from 1994 to about 2000. Quite sluggish and uneconomical, particularly in auto form. Weaknesses are the autobox, and the fuel pump, and like all BMW engines, heads and HG if its have a poor service history. Note, the service interval is a ludicrously low 4500 miles...  ...and it would be a brave man to regularly let it go that long between services. In standard form, too underpowered for the car IMHO.

2.2DTi (UK only, 2001-2003) - GM 4 cylinder lump, using the infamous Bosch VP44 fuel pump. This pump is easily damaged electronically and mechanically by dimwit mechanics cranking it dry rather than bleeding properly. Available in manual form only. Weaknesses are mentioned pump, vacuum issues, poor intake design causing regular "Critical System Malfunction" which is easily overcome with regular cleaning. In standard form, underpowered IMHO.

2.5DTi (non UK, 2001-2003) - BMW 24v common rail lump mated to a 5 speed auto. Never available in RHD form, so irrelevant here.

2.0DTi - rare (in UK), underpowered GM 4 pot lump, nowhere near powerful enough for a 1.7t car.
Title: Re: DTi vs Tdi
Post by: zirk on 08 January 2017, 16:55:59
I kind of miss my 6 pot 2.5TD Manual Estate, good old work horse and would do min 33 mpg all day long no matter how you drove it. would consider getting one again if the right one come up again, fairly rare for a good one these days as there all a bit tied now.

Other option for he Omega is to consider is LPG V6 vs Diesel, ie, pence per mile.
Title: Re: DTi vs Tdi
Post by: Fraggles Rock on 08 January 2017, 19:48:18
Have had a couple of 3.2s previously so wouldn't rule out an LPG V6. :y

However, for project purposes I am thinking manual, (I know, there seems to be alot of this lately...), which pretty much rules out the V6. Reason being I was thinking primarily of supercharging a four cylinder, which the AR25 will probably object to...

Trouble is that most likely means GLS spec, which is pants lol. There's been a 200K mile late DTi Elite on Ebay for a while... Which although clearly tired has potential. Which brings me to my next few questions...

1. I appreciate the lack of the fuller fat Tdi in the UK, but does the BMW diesel use the same subframe as the DTi?

2. Do both engines share a common bell housing bolt pattern?

3. Does the DTi have the same bolt pattern as the later V6 Cdti lump? (I appreciate that this would be a plumbing nightmare...)

That way it opens up potential for more go and all the toys rather than having to retrofit everything...
Title: Re: DTi vs Tdi
Post by: VXL V6 on 08 January 2017, 20:03:37
In answer to 1. - Your going to struggle with the steering box on a RHD model with that engine.... if it was a case of just slapping the block in i'd be running one now!
Title: Re: DTi vs Tdi
Post by: Fraggles Rock on 08 January 2017, 20:08:57
In answer to 1. - Your going to struggle with the steering box on a RHD model with that engine.... if it was a case of just slapping the block in i'd be running one now!
That makes sense. I guess the 24V head pushes the exhaust too far outboard?
Title: Re: DTi vs Tdi
Post by: VXL V6 on 08 January 2017, 20:11:06
In answer to 1. - Your going to struggle with the steering box on a RHD model with that engine.... if it was a case of just slapping the block in i'd be running one now!
That makes sense. I guess the 24V head pushes the exhaust too far outboard?
As far as I understand it, that is the problem.

It's a real shame because that engine opens up a World of upgrades....  :(
Title: Re: DTi vs Tdi
Post by: Fraggles Rock on 08 January 2017, 20:14:46
It is a bugger, but won't rule it out just yet, as could be a case of lateral thinking and a custom manifold to make it work... Assuming that it otherwise bolts straight in of course...

3.5 Tdi lump would make it sit up a bit...
Title: Re: DTi vs Tdi
Post by: Fraggles Rock on 10 January 2017, 19:40:23
Pending further input re the diesel approach...

I have been looking into the petrol one...

Found this...

http://www.ebay.com/itm/Engine-LSJ-Saturn-ION-RED-LINE-supercharged-4-cyl-2-0ltr-ECU-/182417308755?hash=item2a78eb3c53:g:-Z8AAOSwzaJYBXHf&vxp=mtr

A couple of obvious points...

1. The head flow is reversed to the 4 cylinder Omega.
2. The throttle body location isn't ideal for the RWD Omega, will almost certainly foul the bulkhead by the pollen filter.
3. Be blind luck that it would mate to a manual Omega box.

It is at least a GM lump, so could have potential if the issues can be addressed.

Failing that, the other drop in choices would be a Red Top or see if an SLK blower could be persuaded to fit the 2.2...
Title: Re: DTi vs Tdi
Post by: citroenguy on 10 January 2017, 20:57:10
That engine is a supercharged version of the 2.0T/2.2 in the Veccy C/Saab 9-3.
There are turbo kits for the 2.2 mig, but it might be easier to swap for the 2.0 turbo from the Astra G/H
Title: Re: DTi vs Tdi
Post by: Fraggles Rock on 10 January 2017, 22:10:12
That engine is a supercharged version of the 2.0T/2.2 in the Veccy C/Saab 9-3.
There are turbo kits for the 2.2 mig, but it might be easier to swap for the 2.0 turbo from the Astra G/H
Ah ok, so it's a derivative of the Z22... does it use the same high pressure fuel pump :-\

Prefer the idea of linear power delivery than an on/off turbo...
Title: Re: DTi vs Tdi
Post by: Broomies Mate on 10 January 2017, 22:20:35
That engine is a supercharged version of the 2.0T/2.2 in the Veccy C/Saab 9-3.
There are turbo kits for the 2.2 mig, but it might be easier to swap for the 2.0 turbo from the Astra G/H
Ah ok, so it's a derivative of the Z22... does it use the same high pressure fuel pump :-\

Prefer the idea of linear power delivery than an on/off turbo...

I don't follow?  The turbo's on most Petrol engines are low pressure turbo's.  They are not intended to work like a dirty diesel which NEED the turbo for any sort of forward motion.

I'm just guessing, but are you thinking of cars like the Lancer or Impreza which definitely have the 'On/Off' turbo feel? (And of course, any Diesel produced with a Turbo bolted to it).

Title: Re: DTi vs Tdi
Post by: Fraggles Rock on 10 January 2017, 22:49:11
Never driven a normal petrol turbo, so presumed that all turbo cars drive the same, ie on/off :-[

I liked the power delivery of the 3.2, but like I said, am considering something left field, rather than particularly boy racerish :D

The idea being to create a reliable daily driver that shifts when the mood requires. ;)
Title: Re: DTi vs Tdi
Post by: Broomies Mate on 10 January 2017, 23:30:44
Never driven a normal petrol turbo, so presumed that all turbo cars drive the same, ie on/off :-[

I liked the power delivery of the 3.2, but like I said, am considering something left field, rather than particularly boy racerish :D

The idea being to create a reliable daily driver that shifts when the mood requires. ;)

I currently (for the last two years) have owned and driven a 2004 SAAB 9-5 Aero.  It's got a FPT (Full Pressure Turbo) and as standard is extremely enjoyable to drive.

There have been Omega's with this engine fitted.  Afterall, the largest output Vauxhall/Opel Omega is 207HBP with a reasonable amount of torque.  The SAAB 2.3 with TD04 Turbo (as in my car) is 250BHP and 350Nm Torque.  Pop that engine in, and YAY!!!!!!!!!!  Usining the Trionic7 and with a couple of minutes work, it's 275BHP and 400Nm. 

I LOVE LOVE LOVE the Omega, especially the 3.0Elite MFL (The best car to have), but it's not got half the balls, no matter what rev-range to the 9-5.... and the 9-5 is almost as big too.
Title: Re: DTi vs Tdi
Post by: Fraggles Rock on 10 January 2017, 23:47:44
Something like this?

http://www.ebay.co.uk/itm/2004-SAAB-9-5-AERO-SILVER-manual-250-bhp-family-saloon-fsh-cheaper-tax-and-ins/112261059414?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D2%26asc%3D40800%26meid%3Dbb4c0ca9a32e4abfa40e32fe5d17dfd5%26pid%3D100005%26rk%3D3%26rkt%3D6%26sd%3D332079265442 :-\
Title: Re: DTi vs Tdi
Post by: Broomies Mate on 11 January 2017, 00:13:13
Something like this?

http://www.ebay.co.uk/itm/2004-SAAB-9-5-AERO-SILVER-manual-250-bhp-family-saloon-fsh-cheaper-tax-and-ins/112261059414?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D2%26asc%3D40800%26meid%3Dbb4c0ca9a32e4abfa40e32fe5d17dfd5%26pid%3D100005%26rk%3D3%26rkt%3D6%26sd%3D332079265442 :-\

Apart from colour, that is my car.  If you are local, go and drive it - You won't buy anoher Omega that's for sure.
Title: Re: DTi vs Tdi
Post by: Broomies Mate on 11 January 2017, 00:20:30
I reckon that will sell for about £1,900.  I would happily give the seller £1,700 for that tomorrow.

Ho Hum.  :-\
Title: Re: DTi vs Tdi
Post by: Fraggles Rock on 13 January 2017, 19:29:23
It was an example, an engine donor would probably end up being a Copart special rather than a perfectly good car... Don't believe in scrapping summat for the shear hell of it ;)
Title: Re: DTi vs Tdi
Post by: raywilb on 18 January 2017, 23:21:21
I kind of miss my 6 pot 2.5TD Manual Estate, good old work horse and would do min 33 mpg all day long no matter how you drove it. would consider getting one again if the right one come up again, fairly rare for a good one these days as there all a bit tied now.

Other option for he Omega is to consider is LPG V6 vs Diesel, ie, pence per mile.
me too . back in the day I posted that I had just renewed all parts pertaining to front suspension & steering, at the time it had just
gone through a mot & had nearly 13 mths left. I made an appointment with an accident repair shop to check front geometry. 200 mtrs from my destination I got shunted from behind, a write off. my 2.2 dti in my opinion is not a patch on the 2.5td






Title: Re: DTi vs Tdi
Post by: Doctor Gollum on 18 January 2017, 23:23:01
Which, given thetime and money you have put into the dti, says alot :-\