Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: Omegatoy on 21 July 2008, 22:53:18

Title: 2.5 td lump
Post by: Omegatoy on 21 July 2008, 22:53:18
ok it has taken three weeks but i now have the answer !!
It all came about when i had to sort a std td manual a few weeks ago, after fixing it i took it for a spin and couldnt believe it!!! it was CRAP!!!! I honeslty couldnt believe how rubbish it was to drive it   was dog slow and had no guts!! the owner drove  mine and refused to believe it was the same car!! so here we go,
most of you know my TD has a few mods but i have now isolated
the one that gives more low rpm boost and reduces the smoking when the throttle is wide open :y however just as a double check would like to know when yours starts to be felt, as an indication i can feel mine start to boost at around 1200 rpm by 1500 its definetly beginning to pull and finally i get more or less full boost at 2000, dont know if auto owners will be able to feel it as well as manual owners but all my tests have been done in top gear (5th) as this is when you can really feel it, mine is now averaging 49,3 to the gallon taken over three tankfulls and filling up at the same garage same pump every time, if the results match my findings then anyone who wants to know the mod can pm me and will tell them  what it is!!    
Title: Re: 2.5 td lump
Post by: TheBoy on 22 July 2008, 00:55:01
Mine kicks in just before 2k - higher than Adys/Terrys old manual estate with 427 ecu, which came in hard at 1500.  Remember mines an auto though.
Title: Re: 2.5 td lump
Post by: Omegatoy on 22 July 2008, 08:18:23
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Mine kicks in just before 2k - higher than Adys/Terrys old manual estate with 427 ecu, which came in hard at 1500.  Remember mines an auto though.

Noted thanks J but with the inherent slip in the auto it may not affect you driveability to much?
Title: Re: 2.5 td lump
Post by: andyiow on 22 July 2008, 11:15:18
Mine starts at just after the 1700 mark on a non chipped N-Reg TD. Goes well once the turbo is up and running. Once going it does go into the 3 figure speed mark (not over here but on a 'proper' autobahn).

Next upgrade will be a ECU chip for a better mpg.
Title: Re: 2.5 td lump
Post by: osealy on 22 July 2008, 15:14:55
Mine only get's 30-34????
Best I ever managed was 38 or is 49.3 Kpg.
Title: Re: 2.5 td lump
Post by: Pitchfork on 22 July 2008, 19:53:12
Mines arourd 2k ish & it's also an auto
As I get 33mpg at the very best I would love to know how economy can be improved (I dream of 49.3mpg)
Title: Re: 2.5 td lump
Post by: TheBoy on 23 July 2008, 18:50:09
a chipped manual tractor should easily acheive high 40s mpg.

Ignoring a fuel leak, mine was doing low 40s (auto) averaged over a few tanks
Title: Re: 2.5 td lump
Post by: Pitchfork on 23 July 2008, 19:16:50
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a chipped manual tractor should easily acheive high 40s mpg.

Ignoring a fuel leak, mine was doing low 40s (auto) averaged over a few tanks
When did you sell your soul at the crossroads?? :'(
Title: Re: 2.5 td lump
Post by: Omegatoy on 25 July 2008, 07:43:20
 ok so far it ooks like its worthwhile but with only five people voting?? come on td owners hit the button!! just need to know when you feel it boosting  and so far only mine is doing it that low!! :y
Title: Re: 2.5 td lump
Post by: zirk on 25 July 2008, 16:53:23
voted 2 to 2.5, also pm sent for the answer?
Title: Re: 2.5 td lump
Post by: Pitchfork on 25 July 2008, 18:35:03
Please put us out of our misery if you have a magic trick for improving mpg!
Title: Re: 2.5 td lump
Post by: Omegatoy on 25 July 2008, 20:02:33
Chipping is the answer to better economy aas well as power the other mods i have done have all improved the beast further, this particular one is just aimed at bring the boost in earlier to make it easier to drive,
Omegatoy
Title: Re: 2.5 td lump
Post by: TheBoy on 25 July 2008, 20:54:52
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Please put us out of our misery if you have a magic trick for improving mpg!
Chipping, but sadly need a manual (ideally) or an AR35 autobox.
Title: Re: 2.5 td lump
Post by: Pitchfork on 26 July 2008, 09:22:39
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Quote
Please put us out of our misery if you have a magic trick for improving mpg!
Chipping, but sadly need a manual (ideally) or an AR35 autobox.
For those of us with AR25s, would it be feasible to produce a chip with the lower turbo boost (for economy) but without the other tricks that increase torque & thereby destroy the gearbox?
Title: Re: 2.5 td lump
Post by: TheBoy on 26 July 2008, 16:04:12
Quote
Quote
Quote
Please put us out of our misery if you have a magic trick for improving mpg!
Chipping, but sadly need a manual (ideally) or an AR35 autobox.
For those of us with AR25s, would it be feasible to produce a chip with the lower turbo boost (for economy) but without the other tricks that increase torque & thereby destroy the gearbox?
Not really, as the AR25 is right at the limit anyway - so any increases would destroy it soon
Title: Re: 2.5 td lump
Post by: Pitchfork on 26 July 2008, 16:40:43
Quote
Quote
Quote
Quote
Please put us out of our misery if you have a magic trick for improving mpg!
Chipping, but sadly need a manual (ideally) or an AR35 autobox.
For those of us with AR25s, would it be feasible to produce a chip with the lower turbo boost (for economy) but without the other tricks that increase torque & thereby destroy the gearbox?
Not really, as the AR25 is right at the limit anyway - so any increases would destroy it soon
Ah! so a lower boost threshold will increase the torque??
Would not the torque at low revs be the same as it is when the turbo normally kicks in - just earlier in which case how would it place additional stress on the box?
I'm interested to understand the theory :)
Title: Re: 2.5 td lump
Post by: Dodger on 26 July 2008, 21:33:18
Mine comes in at about 1700 - 2000, much like  TB's and again, is an auto box. regards MPG, I'm lucky to see 30 round town, and 35 on long journeys. :(
Desperately need an AR35 + a chip me thinks... trouble is, finding a decent AR35, at a sensible price, + fitting + chip..
(My old rover estate did 50+ around town, and 60+ on a run!!)

Title: Re: 2.5 td lump
Post by: tunnie on 26 July 2008, 21:35:02
Quote
Mine comes in at about 1700 - 2000, much like  TB's and again, is an auto box. regards MPG, I'm lucky to see 30 round town, and 35 on long journeys. :(
Desperately need an AR35 + a chip me thinks... trouble is, finding a decent AR35, at a sensible price, + fitting + chip..
(My old rover estate did 50+ around town, and 60+ on a run!!)


something not right there!
Title: Re: 2.5 td lump
Post by: Elite Pete on 26 July 2008, 22:52:08
I removed the cat on my Rover 25 wiesel and it boosts so much earlier and it still passes its MOT ;)
Title: Re: 2.5 td lump
Post by: dieseldean on 27 July 2008, 00:19:57
mine does workrun 40%motorway 60% uphill downdale. it comfortably manages 45-48mpg on this daily chore. it's worst economy achievment 31.4 grossing 3.44tonnes dragging caravan in scottish highlands. if it is so good then why the hell does it flat spot at 3500rpm but only at around 75mph in 4th and around 95mph in 5th
Title: Re: 2.5 td lump
Post by: Pitchfork on 27 July 2008, 12:19:42
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mine does workrun 40%motorway 60% uphill downdale. it comfortably manages 45-48mpg on this daily chore. it's worst economy achievment 31.4 grossing 3.44tonnes dragging caravan in scottish highlands. if it is so good then why the hell does it flat spot at 3500rpm but only at around 75mph in 4th and around 95mph in 5th
What! most of use seem to get circa 33mpg on a run
Is it a manual or automatic?
Has it been chipped?
There are a lot of jealous people out here
Title: Re: 2.5 td lump
Post by: Pitchfork on 27 July 2008, 12:21:39
Quote
Quote
Mine comes in at about 1700 - 2000, much like  TB's and again, is an auto box. regards MPG, I'm lucky to see 30 round town, and 35 on long journeys. :(
Desperately need an AR35 + a chip me thinks... trouble is, finding a decent AR35, at a sensible price, + fitting + chip..
(My old rover estate did 50+ around town, and 60+ on a run!!)


something not right there!
It's better than I can get, so what do you think it should be??
Title: Re: 2.5 td lump
Post by: dieseldean on 27 July 2008, 14:55:57
if driven like the cheapskate i can be, it does really good on fuel. but when i feel like being a young boyracer again the car just won't have it. car has been in family for 10years and economy gets better but performance gets lost.  its a manual and if it ever been chipped it would have been done over 10 year ago.
Title: Re: 2.5 td lump
Post by: osealy on 27 July 2008, 16:54:14
40-50 mpg!!!!! I hope you aren't just quoting the computer!
My 3 TD auto estates MIDs  gave 38.  57  28 . for av mpg.  They were all 30-34 . 1 with MAF (smoother) 2 without.
I tried to see where boost came in with snow start , but convertor slippage muddied any idea, ::)
Title: Re: 2.5 td lump
Post by: Pitchfork on 27 July 2008, 17:19:48
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40-50 mpg!!!!! I hope you aren't just quoting the computer!
My 3 TD auto estates MIDs  gave 38.  57  28 . for av mpg.  They were all 30-34 . 1 with MAF (smoother) 2 without.
I tried to see where boost came in with snow start , but convertor slippage muddied any idea, ::)
My best case 33 mpg was calculated over quite a period
(GLS does not have a MID)
Title: Re: 2.5 td lump
Post by: dieseldean on 27 July 2008, 19:04:04
feel and hear the turbo from start but boost at 2250rpm. but loses it  at around 3500rpm. my car is excellent on fuel but will never let me have fun!