Omega Owners Forum

Chat Area => General Discussion Area => Topic started by: JamesV6CDX on 25 October 2007, 00:52:46

Title: 3.0 cams in a 2.5 Vs fuel economy
Post by: JamesV6CDX on 25 October 2007, 00:52:46
I am aware that if I thrash it then the fuel will be sucked up (!)... but can someone with experience of this, advise if I will see a drop in consumption, during everyday careful driving, if I fit 3.0 cams to my 2.5?

Cheers :)
Title: Re: 3.0 cams in a 2.5 Vs fuel economy
Post by: Andy B on 25 October 2007, 09:27:53
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I am aware that if I thrash it then the fuel will be sucked up (!)... but can someone with experience of this, advise if I will see a drop in consumption, during everyday careful driving, if I fit 3.0 cams to my 2.5?

Cheers :)

I don't know the actuall fuel consumption but I know someone who sold his 2.5 V6 shortly after he'd fitted 3.0 cams because of the horendous fuel consumption. He replaced it with a 2.5 diseasal. :y  :y
Title: Re: 3.0 cams in a 2.5 Vs fuel economy
Post by: JamesV6CDX on 25 October 2007, 13:01:12
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I am aware that if I thrash it then the fuel will be sucked up (!)... but can someone with experience of this, advise if I will see a drop in consumption, during everyday careful driving, if I fit 3.0 cams to my 2.5?

Cheers :)

I don't know the actuall fuel consumption but I know someone who sold his 2.5 V6 shortly after he'd fitted 3.0 cams because of the horendous fuel consumption. He replaced it with a 2.5 diseasal. :y  :y

Bleh, I used to drive a 4 litre V8 range rover, it can't be any worse ;D
Title: Re: 3.0 cams in a 2.5 Vs fuel economy
Post by: ians on 25 October 2007, 17:02:04
I'm getting c. 25mpg out of my newly acquired 3L auto Elite vs 32mpg from my 2.5 manual estate.   same driver same journeys.   Bigger difference than I expected, but not really sure if its due to the auto or the 3L (or a fault..)
Title: Re: 3.0 cams in a 2.5 Vs fuel economy
Post by: ffcgary1 on 26 October 2007, 00:35:14
 James, i have noticed that the fuel consumption on a run has fallen by about 3-4 mpg and maybe 6 on town runs so dont worry about that too much. :y :y
Title: Re: 3.0 cams in a 2.5 Vs fuel economy
Post by: Paul M on 26 October 2007, 00:50:00
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I'm getting c. 25mpg out of my newly acquired 3L auto Elite vs 32mpg from my 2.5 manual estate.   same driver same journeys.   Bigger difference than I expected, but not really sure if its due to the auto or the 3L (or a fault..)

Bit of both... my 3.0 manual averages 26 MPG but then I rag the tits off it. I expect a well driven 3.0 manual to be approaching 30 MPG on combined driving.
Title: Re: 3.0 cams in a 2.5 Vs fuel economy
Post by: JamesV6CDX on 26 October 2007, 03:39:04
Funny all the replies suggest much lower economy.

My thoughts (IMHO) would be this:

1) The increased cam lift will aid combustion and make the engine more efficient.

2) Having owned both 2.5 and 3.0 Omegas (several of each) I have never really noticed much difference between the 2.5 and 3.0 engines economy wise, but the 3.0 is definately quicker and more responsive at higher cruising speeds..

3) Bearing point two in mind, I'd have thought a 2.5manual with 3.0 cams is the bet mix of performance and economy?



Title: Re: 3.0 cams in a 2.5 Vs fuel economy
Post by: TheBoy on 26 October 2007, 18:54:26
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2) Having owned both 2.5 and 3.0 Omegas (several of each) I have never really noticed much difference between the 2.5 and 3.0 engines economy wise, but the 3.0 is definately quicker and more responsive at higher cruising speeds..
Autos, should be 24-25 from 3.0, around 30 for 2.5.  Add about 3 mpg for manual
Title: Re: 3.0 cams in a 2.5 Vs fuel economy
Post by: Big Fra on 26 October 2007, 19:04:13
Oh, so then 22-24 ish isn't too good then?
Title: Re: 3.0 cams in a 2.5 Vs fuel economy
Post by: miggy on 26 October 2007, 19:33:09
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2) Having owned both 2.5 and 3.0 Omegas (several of each) I have never really noticed much difference between the 2.5 and 3.0 engines economy wise, but the 3.0 is definately quicker and more responsive at higher cruising speeds..
Autos, should be 24-25 from 3.0, around 30 for 2.5.  Add about 3 mpg for manual

Jamie

What do you reckon to 17 mpg, I have been using the 2.6 for work this week, only 6 mile round trip, in traffic around town, I thought it was due to the short daps and stop, starts.

 :question :question
Title: Re: 3.0 cams in a 2.5 Vs fuel economy
Post by: TheBoy on 26 October 2007, 19:56:06
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2) Having owned both 2.5 and 3.0 Omegas (several of each) I have never really noticed much difference between the 2.5 and 3.0 engines economy wise, but the 3.0 is definately quicker and more responsive at higher cruising speeds..
Autos, should be 24-25 from 3.0, around 30 for 2.5.  Add about 3 mpg for manual

Jamie

What do you reckon to 17 mpg, I have been using the 2.6 for work this week, only 6 mile round trip, in traffic around town, I thought it was due to the short daps and stop, starts.

 :question :question
That short a journey, 17 sounds about right, esp if auto....  ....my figures were 'average' use (or what I would class as average - a mix of A/B roads, short stretches of dual carriageway).
Title: Re: 3.0 cams in a 2.5 Vs fuel economy
Post by: miggy on 26 October 2007, 19:58:33
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2) Having owned both 2.5 and 3.0 Omegas (several of each) I have never really noticed much difference between the 2.5 and 3.0 engines economy wise, but the 3.0 is definately quicker and more responsive at higher cruising speeds..
Autos, should be 24-25 from 3.0, around 30 for 2.5.  Add about 3 mpg for manual

Jamie

What do you reckon to 17 mpg, I have been using the 2.6 for work this week, only 6 mile round trip, in traffic around town, I thought it was due to the short daps and stop, starts.

 :question :question
That short a journey, 17 sounds about right, esp if auto....  ....my figures were 'average' use (or what I would class as average - a mix of A/B roads, short stretches of dual carriageway).

Thanks mate

 :y :y