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  #1  
Old 14th August 2013, 04:44 PM
locost-turbo locost-turbo is offline
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Default omega what parts did u use?

hi all

my first post so be gentle, I have pm'd a couple of lads I know using the omega. just wondering if anyone else has gone down this route and what parts u used from the omega.

I want to use gearbox, prop and diff. as want the 2.3 saab lump. but to keep costs down what else can the omega offer? hubs? steering? suspension? driveshafts?

I don't want to get whole car if all I am using is the gearbox, prop and diff?

who has used this?

what were your build issue's?

what if u could start again would u change.

thanks all

nick
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  #2  
Old 14th August 2013, 08:06 PM
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alga alga is offline
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The accepted wisdom on this forum has been to use as much Sierra parts as possible, Sierra hubs even if you want some exotic engine (or Mazda MX-5). But if you feel confident enough that you'll find your way around, you can try building a GM-based roadster. Never done on this forum, AFAIK.

That said, AshG used a SAAB turbo lump to replace the small Pinto after one year of riding, he might give you some pointers.
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  #3  
Old 15th August 2013, 08:06 AM
beardydave beardydave is offline
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Hi,

Good to see another person trying to squeeze a Saab lump in.

Accepted wisdom regarding omega boxes is that you add a 0 to the number on the box and you have the limit in Nm. I.e. R28 can safely take 280Nm. They did do an R35, but only on the rare 3.2 v6 manual. Now a Saab 2.3 Aero from a 9000 puts out 350 before you play with it, so you'll need to map the ecu very conservatively, not least because in something as light as a roadster you'll just be lighting the tyres all the time.

As a result I've got an e36 328 gearbox with a saab bell housing welded on. It cost someone else a lot of money, but it's supposed to be indestructible...

You can get custom bell housings to fit a gm euro block pattern engine like the saab to either a Ford t9 or t5 gearbox with a cable clutch. They are supposed to be much stronger than the gm boxes.

I'm nearly ready to start mocking up my engine mountings, so when I'm done I can send you on some dimensions if you want. I am going down the dry sump route though as the saab engines have an oil starvation issue when used RWD, so I might be too low for you.

It's probably a long way off, but I can help with the ecu mapping too.

Last edited by beardydave : 15th August 2013 at 04:26 PM.
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  #4  
Old 15th August 2013, 12:27 PM
jps jps is offline
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I guess using Sierra bits as much as possible means you can use the Book designs for the wishbones etc, same argument for using MX5 bits - and the designs people have come up with for Mazda based builds.

If you start using other donors you'll presumably need to compensate for different suspension geometry and change the designs, which would be well beyond me, although perhaps you are happy to do so?

Sounds like using a custom bell housing to allow the use of a Ford box would be an easy way to get the engine you want - and allow you to follow the Book design faithfully - but as you say all you then want is the Omega engine...

Whereabouts are you? I've got a Sierra with the engine and box removed if you are thinking of getting hold of some Ford running gear for your build...?
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  #5  
Old 15th August 2013, 05:07 PM
locost-turbo locost-turbo is offline
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hi all

thanks for the updates. I am worried that the ford box will break without spending a grand on it. I am hoping that the r28 gearbox will handle the saab lump because its soooo much lighter that the omega bus.

looks like I just need gearbox diff and prop from the omega. and try to find a cheap seirra. I am in gedney. so north cambs/ south lincs. and will need everything other than the engine and gearbox.

as for engine mapping it will have to be restricted in first and second for sure and r888's on the back :0).

email sent to handy andy for a price of pre cut kit. build table to be collected at the weekend.

now for some welding practice
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  #6  
Old 15th August 2013, 05:19 PM
locost-turbo locost-turbo is offline
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or to keep it really simple keep my eyes pealed over next year for a race spec ford box there's lots around. means I can crack on with the build knowing that ill need a decent box. save hassle of hydraulic cluth as well.

money ill save on buying an omega will go halfway towards the parts to rebuild a t9. at least I can pick my ratio's if I build one myself.

I am not brave enough to go where noone has been before. suspension geometry is not my specialist subject I am afraid.

thanks again
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  #7  
Old 15th August 2013, 07:28 PM
beardydave beardydave is offline
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Having gone down the route of trying to fit in a BMW 750 rear diff and giving up on drive shaft lengths and off-set input flanges wanting to occupy the same space as my left kidney...

I've gone down the Ford diff route, simply because the chassis is designed for it already.

This way I just have to modify the prop-shaft to meld the BMW and Ford shafts, rather than two driveshafts. And i'd have to shorten the ford shaft for a standard build anyway.

The advantage of the Ford diff is the abundance of cheap LSDs from the cosworths. For the omega diff you'd need to get one from quaife. £££

Plus the quaife one will be an ATB diff which won't be much use once both wheels are spinning. I believe the Ford Cosworth diff is a proper plated diff which will keep the rear axle locked even after you've broken traction.
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  #8  
Old 15th August 2013, 07:41 PM
locost-turbo locost-turbo is offline
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thanks for that. I think I will go down the ford route. no learning all that is ford geearbox. t9, t5? mt75. but again think the stronger gearboxes are bigger and need chassis mods.

if it was my second build I would not be phased but first one. prob should follow the book as best I can

n
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  #9  
Old 15th August 2013, 09:22 PM
beardydave beardydave is offline
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That's been my plan.

Next build will have an aluminium chassis with wider transmission tunnel to take the bmw diff, and wider rear and front track to compensate. And integral roll cage designed in from the start, and possibly fuel tank relocated within the wheel base.

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  #10  
Old 15th August 2013, 10:34 PM
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twinturbo twinturbo is offline
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the only type 9 that will take big power will be a quaif one. you won't see change from a few grand.

MT75 will last ok but it's a fixed belhousing unless you find or buy one of the special non integral boxes.

T5 is more than man enough , and there is more than likly a belhousing out there.

TT
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