Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: Martin_1962 on 25 September 2007, 12:26:28

Title: Tuning a 2.6
Post by: Martin_1962 on 25 September 2007, 12:26:28
OK here are my requirements

1) Boost bhp to about 200
2) Boost mid range torque (2500 to 3500 range)
3) Not lose anything over 2000rpm
4) Not too expensive

I am prepared to

1) Not drop below 99RON on fuel
2) Remove heads
3) Replace some engine components
3) Accept a small loss below stall speed.

Can't quite afford a 3.2 or the hassle of changing.

I think heads may need to be removed as there is no way I can do the exhaust manifolds in situ and 1 is blowing when cold.

Any ideas anyone?
Title: Re: Tuning a 2.6
Post by: Rebel1 on 25 September 2007, 12:46:31
For £299 Superchips.co.uk will give you an additional 13BHP and 24 lb ft...seems a reasonable place to start.
Title: Re: Tuning a 2.6
Post by: Markie on 25 September 2007, 12:47:09
your really looking for that sort of increase to be changing to 3.2 cams...

Not sure if the 2.6 to 3.2 is as easy and productive as 2.5 to 3.0  :-/
Title: Re: Tuning a 2.6
Post by: VXL V6 on 25 September 2007, 12:54:12
The insurance is going to be affected as well by doing engine modifications.
Title: Re: Tuning a 2.6
Post by: Martin_1962 on 25 September 2007, 12:58:55
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your really looking for that sort of increase to be changing to 3.2 cams...

Not sure if the 2.6 to 3.2 is as easy and productive as 2.5 to 3.0  :-/


Not even sure which cams are used in the DBW engines?
Title: Re: Tuning a 2.6
Post by: Rebel1 on 25 September 2007, 13:10:25
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The insurance is going to be affected as well by doing engine modifications.

Only if you tell them - as an ex-claims manager, I know that the insurers and their engineers that inspect written off cars aren't set up to look for these kinds of engine mods...they look for non-standard wheels, body kits, big exhausts etc.
Title: Re: Tuning a 2.6
Post by: Martin_1962 on 25 September 2007, 13:22:03
Last time I enquired - no chips for 2.6 so I have asked them again
Title: Re: Tuning a 2.6
Post by: Martin_1962 on 25 September 2007, 13:23:57
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The insurance is going to be affected as well by doing engine modifications.

Only if you tell them - as an ex-claims manager, I know that the insurers and their engineers that inspect written off cars aren't set up to look for these kinds of engine mods...they look for non-standard wheels, body kits, big exhausts etc.

I think with these cars they care little anyway, I have quite a big mod already and it made no difference to insurance. (My LPG kit), towbar made no difference either.
Title: Re: Tuning a 2.6
Post by: Dazzler on 25 September 2007, 13:29:59
I don't think they do a chip as such but they can remao your ECU via a laptop. The other option is get a 3.0......
Title: Re: Tuning a 2.6
Post by: Rebel1 on 25 September 2007, 13:32:13
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The insurance is going to be affected as well by doing engine modifications.

Only if you tell them - as an ex-claims manager, I know that the insurers and their engineers that inspect written off cars aren't set up to look for these kinds of engine mods...they look for non-standard wheels, body kits, big exhausts etc.

I think with these cars they care little anyway, I have quite a big mod already and it made no difference to insurance. (My LPG kit), towbar made no difference either.

Insurers definately wouldn't care about towbars and lpg conversions - they don't make the car go faster and don't make them more attractive to TWOCers
Title: Re: Tuning a 2.6
Post by: cem_devecioglu on 25 September 2007, 14:15:25
With my previous car the biggest tork gain was from the head work as a result increasing the compression ratio..(not sure this can be done cheap style if you dont have friends in related jobs)

Changing the cams also will improve performance radically..(second hands can be cheap)

workin on valves (sure expensive eliminated)

exhaust manifolds+boxes can change the picture.. (quite pricey)

chip (sure is most cheap way)

other mods needs modification on cooling also(outside the subject)

But whatever you do consumption will be effected or you will get very little gain...if I'm not wrong..

Maybe will  be necessary to change ECU remap (also for lpg)





Title: Re: Tuning a 2.6
Post by: Martin_1962 on 25 September 2007, 14:34:53
My car could easily handle more ignition advance and higher compression ratio.

The cams as supplied are quite mild, but I don't know the fitments on the DBW engines, need someone with EPC to list all the variants.

Higher CR and more advance would help consumption rather than hinder, the LPG system follows the petrol system so would not need too much tweaking.

Cooling - same basic design is OK to around 220 - 240.

As to twockers - Omegas do not excite them - espeially with the good security they have.

Basically I want to make better use of 99RON petrol and 105RON (I think) gas.

The Y engines are lower compression, is the drop due to head design or piston design?

I have seen big increases due to CR improvements 10bhp at wheels on a 1600
Title: Re: Tuning a 2.6
Post by: Kevin Wood on 25 September 2007, 17:15:02
Fitting more lairy cams will reduce the torque at low RPM. There's always a compromise with changing just cams as you are effectively moving the range of revs over which the engine breathes effectively. I'm sure someone who's got 3.0 cams in a 2.5 will be along to quantify this. May not be worth worrying about with a relatively modest cam change. Need to know if there's a similar spec. difference between 2.6 and 3.2 though.

Porting heads, fitting bigger valves, etc. tends to be more effective at high RPM, in conjunction with cam changes because that's the area where restrictions in gas flow start to become significant. Low RPM tends to suffer again because gas velocity reduces and the engine burns less efficiently.

If it's mid range torque you want the best solution is probably more cubes - i.e. a 3.2  :-/

However, upping the compression would also help and, given that you are on LPG that might be an interesting option. If the pistons are flat on all these engines the differences are in the combuston chamber volume. You just need to do the sums for each engine and see what'd work. Formula Here: http://en.wikipedia.org/wiki/Compression_ratio

Maybe a set of 2.5 heads would be a good option if they could be made to fit? Not sure if they'd make a significant difference - did the 2.5 have higher compression than the 2.6 or was it just the 3.0 / 3.2 that differed in this respect?

Sorting out the exhaust with a proper pair of tubular manifolds with the primaries tuned would also make an improvement in torque, I reckon. I hope somebody tries it one day 8-)

Kevin

Title: Re: Tuning a 2.6
Post by: cem_devecioglu on 25 September 2007, 18:07:03
Increase in compression ratio will also increase midrange torque values.

Exhaust+manifold+valve modification will shift high torques to higher RPMs thats normal.

for cooling I see somewhere else the oil cooler in mega is taken out from the engine (external oil cooler by air)..

And someone open extra cooling holes behind the engine bay for cooling cylinders 5-6 (dont know how !!)

Wish omegas had vanos similiar apparats but unfortunately not..

PS: my experience from previous car mod :  better spend more money and invest bigger engine..
Title: Re: Tuning a 2.6
Post by: TheBoy on 25 September 2007, 18:19:22
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Any ideas anyone?
Unhitch your house from the back...
Title: Re: Tuning a 2.6
Post by: Martin_1962 on 25 September 2007, 18:51:24
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Any ideas anyone?
Unhitch your house from the back...
>:( >:(
Title: Re: Tuning a 2.6
Post by: Kevin Wood on 25 September 2007, 19:51:52
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better spend more money and invest bigger engine..

This is sound advice. Other than the little things like a change to 3.0 cams, chipping, etc. If your tuning gets any more serious than this, your starting point should be the engine that's closest to your requirements off the shelf because every step from then on costs money and takes you into the unknown in some respects. This means the biggest one  ;) unless you need to keep below a certain capacity for some reason or the smaller engine is stronger.

I still think the exhaust is worth playing with, though. A properly designed exhaust will wake the engine up in the midrange.

Kevin
Title: Re: Tuning a 2.6
Post by: Markie on 25 September 2007, 19:59:04
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better spend more money and invest bigger engine..

This is sound advice. Other than the little things like a change to 3.0 cams, chipping, etc. If your tuning gets any more serious than this, your starting point should be the engine that's closest to your requirements off the shelf because every step from then on costs money and takes you into the unknown in some respects. This means the biggest one  ;) unless you need to keep below a certain capacity for some reason or the smaller engine is stronger.

I still think the exhaust is worth playing with, though. A properly designed exhaust will wake the engine up in the midrange.

Kevin


Thats all very well for you to say Mr Late model immaculate 3.2  ;) ;D

(check my signature!!!)
Title: Re: Tuning a 2.6
Post by: Martin_1962 on 25 September 2007, 19:59:58
Seems a pity to dump the Y26 when a Y32 is not that cheap - I don't want to spend a fortune - just see what is easy.

Cams - no-one seems to know what is in a 2.6.

I reckon that 200bhp is reachable and affordable.

Long term would be a Y32SE and AR35 transplant but that would be two years away minimum. (when HP finishes)
Title: Re: Tuning a 2.6
Post by: VXL V6 on 25 September 2007, 20:14:32
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Long term would be a Y32SE and AR35 transplant but that would be two years away minimum. (when HP finishes)

Good point, if you push the torque figure up I guess you'll increase the stress on the AR25 box (I'm assuming it's an AR25 on a 2.6).
Title: Re: Tuning a 2.6
Post by: Martin_1962 on 25 September 2007, 20:25:17
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Long term would be a Y32SE and AR35 transplant but that would be two years away minimum. (when HP finishes)

Good point, if you push the torque figure up I guess you'll increase the stress on the AR25 box (I'm assuming it's an AR25 on a 2.6).

Pretty sure it is.

As to "why not swap the car?" well I like it and there are not that many cheap facelifts in good condition
Title: Re: Tuning a 2.6
Post by: cem_devecioglu on 25 September 2007, 20:36:58
Although +20 from the normal is not a far goal the car prices there in your country is comparingly cheap.

just an idea instead of modding, buying a newer healthier bigger engine may be worth..



Title: Re: Tuning a 2.6
Post by: Martin_1962 on 25 September 2007, 20:38:54
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Although +20 from the normal is not a far goal the car prices there in your country is comparingly cheap.

just an idea instead of modding, buying a newer healthier bigger engine may be worth..




Newer car three isn't many and they also have some sily features like no intermittant wipers, two  years time for the Y32/AR35
Title: Re: Tuning a 2.6
Post by: VXL V6 on 25 September 2007, 20:46:18
Personally if I've spent money to buy the car originally, spent lots of time and money getting up to a maintenance level that i'm happy with (serviced regularly, genuine parts, everything working as it should) and therefore feel confident about it's reliability then the last thing I want to do is trade it in so somebody else benefits and then have to start all over again......

For me it's only when a car becomes uneconomic to repair to MOT standard when it's getting older that I would think to change it.
ie. if it was going rotten and two or more other things also needed to be done to get it through.

Just my thoughts!!!
Title: Re: Tuning a 2.6
Post by: cem_devecioglu on 25 September 2007, 20:49:15
The last time I start modding I end up with an unhealthy powerful car  which I spent twice money than its worth

PS: now I dont touch mega other than standard replacements..But even changing sensors make the car more responsive..And I dont plan to sell for a long time also..
Title: Re: Tuning a 2.6
Post by: Kevin Wood on 25 September 2007, 20:50:34
Quote
Quote
Quote
better spend more money and invest bigger engine..

This is sound advice. Other than the little things like a change to 3.0 cams, chipping, etc. If your tuning gets any more serious than this, your starting point should be the engine that's closest to your requirements off the shelf because every step from then on costs money and takes you into the unknown in some respects. This means the biggest one  ;) unless you need to keep below a certain capacity for some reason or the smaller engine is stronger.

I still think the exhaust is worth playing with, though. A properly designed exhaust will wake the engine up in the midrange.

Kevin


Thats all very well for you to say Mr Late model immaculate 3.2  ;) ;D

(check my signature!!!)


That probably didn't end up sounding the way I intended. What I meant is that it doesn't cost any more to start with a 3.2 than a 2.6 and your first 40BHP come for free. Of course if you've already got a 2.6 in your car it's a different matter.

Anyway, my 3.2 is no longer immaculate thanks to a biker who decided to use my front bumper as a safety barrier on a mountain pass in Italy  >:( >:( :'(

Kevin
Title: Re: Tuning a 2.6
Post by: Martin_1962 on 25 September 2007, 22:16:59
I do have plans when paid for.

3.2 with higher CR, better mounted LPG nozzles
Title: Re: Tuning a 2.6
Post by: Markjay on 25 September 2007, 23:19:14
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PS: my experience from previous car mod :  better spend more money and invest bigger engine..

'There is no replacement for bigger displacement'  8-)