Donar Dilemma

[Trif]

I am at the stage of my build where I have completed my chassis (except engine mounts), stripped my sierra estate (1800 CVH) and I am part way through making the suspension/steering etc (Just machining my mushrooms). Now the sensible advice on the forum seems to lean towards “get it through the IVA with the CVH and then put in something meatier. (which I am doing). However I have just acquired a 2.0 ltr Omega, one owner from new, garaged serviced (with paperwork) 30,000 miles on the clock, really mint. My question is this, Are there any chassis mods that I would be better off doing now, not really concerned about engine mounts more about clearances etc OR should I consider putting the engine and box into the build now as standard and modify the engine post IVA?

[Bonzo]

Hi Trif

I can see the attraction of a mint Ecotec engine :cool:

Possibly the only major thing that needs investigation is the choice of gearbox that you will be using on the Ecotec engine.

Perhaps it would be wise to measure up the Omega's gearbox in order to double check if it will fit into the type 9 transmission tunnel of your chassis .... My thinking is the Omega box is a bit chunkier than the Ford type 9, you may require the MT75 transmission tunnel in your build .

There is a bell housing available to fit the type 9 box to the Ecotec though.

Not a lot of help, I know but food for thought :)

[twinturbo]

My thoughts were similar.

So long as the gearbox goes in then the rest can be sorted fairly easily.

There's at least one builder with an XE, may be worth tryign to contact them.

It's a Getrag 240 box

http://cgi.ebay.co.uk/VAUXHALL-OMEGA-2-0-16V-5-SPEED-MANUAL-GEARBOX-/150459056472?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item23080f0158

looks quite compact if a little wide at the bellhousing.

TT

[Trif]

Thanks for that lads, if I use the omegas' engine and box (with possible tunnel mods) I'd need to use the omega loom and instruments. Am I close to ending with a Q plate if I leave the rest as Sierra donar?

[twinturbo]

It will definatly have a Q-Plate if it's mixed and matched.

The omega may have security systems and imobaliser on the key. So bear that in mind when taking apart the loom. May be worth askign on MIG Web or simmilar.

TT

[Bonzo]

Personaly I think it will be more straight forward to complete the build from your single Sierra donor, provided your paperwork is in order, you should qualify for an age related plate.

In theory, you can build with a different engine & still qualify for an age related plate.
That said, you do risk opening up a can of worms as some local DVLA offices may have a different view & slap you with a Q plate.

If you use both engine & Gearbox prior to IVA you'll almost certainly be given a Q plate.

You have not stated the age of your Omega, it could be entirely possible that you may need to fit a CAT to meet the emission requirement's for your engines age !!??

[Trif]

I think you've cleared my mind, I'll continue the sierra build (but put in the tunnel mods) get it through on an age related plate and then swap to the omega. With regard to the omega age it's 12 years old.

[Bonzo]

That'll be a 1998 R/S plate & would need a CAT fitted if installed pre IVA :eek:

[Trif]

That'll be a 1998 R/S plate & would need a CAT fitted if installed pre IVA :eek:

I'll bear that in mind. I am I right in assuming that that wouldn't be the case if fitted after the IVA?

[snapper]

Once you have gone through IVA you will have emissions set on the V5 based on the engine age at IVA, after that any engine will be ok as long as the emissions are as stated or better than on the V5

[mr henderson]

If you plan to use the Getrag box, check the 5th gear ratio, as some Getrag boxes are direct top, and require a suitable long-legged diff ratio to loower cruisng revs to a tolerable level.

[Trif]

If you plan to use the Getrag box, check the 5th gear ratio, as some Getrag boxes are direct top, and require a suitable long-legged diff ratio to loower cruisng revs to a tolerable level.

What sort of ratio should I be targeting and how do I tell if the box is a direct top?
Trif

[mr henderson]

What sort of ratio should I be targeting and how do I tell if the box is a direct top?
Trif

Ford boxes are usually in the region of .87 for 5th gear, so a diff ratio of 3.6 ish is ok. If your box is direct top then you would be looking for a diff ratio of around 3.1 For your box google with all the details would be a good place to start, alternatively find a way of turning the input shaft and see what the output does.

[twinturbo]

3.14 Sierra Diffs Are very very rare!

TT

[mr henderson]

3.14 Sierra Diffs Are very very rare!

TT

Indeed, which is why he needs to check the gearbox.

[Trif]

Thankyou to everyone that has taken the trouble to give me help with this matter. I've got loads to go on now, and the first job will be to modify the chassis so that it will accomodate the engine and box. I'm going to follow the path of using the sierra donar, secure an age related plate and then convert to the Omega drive train................. I think!
Cheers Trif