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Discussion Starter #1
Excuse my naivety, but why are the CDTI's more economical (better mpg), than the older DTI's? What's the difference in engine design?
Thanks.
 

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^^^that^^^.
the common rail system works like a petrol injection system (instead of the mechanical pump type on the older engines) so it can change timing and amount to suit load/rpm, rather than having to compromise. thats also why they pick up a lot sooner and make more power.
 

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Discussion Starter #4
Siraf,
Thanks for the info. Are the exhaust manifolds on the CDTI's set at a higher compression?

So I presume it's natural progression, a bit like going from spi to mpi (petrol engine comparison)? Or even VVT.

Think in a few years time when I change my good old 1.6 8v Astra I may consider a diesel cdti, like the extra power & economy.
 

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Siraf,
Thanks for the info. Are the exhaust manifolds on the CDTI's set at a higher compression?
that doesnt make sense really? do you mean the compression ratio or the turbo's boost pressure level?

So I presume it's natural progression, a bit like going from spi to mpi (petrol engine comparison)? Or even VVT.
similar, yeah but common rail from mechanical is more like the jump from a single carb to mpi. there's a massive difference in how they drive.

Think in a few years time when I change my good old 1.6 8v Astra I may consider a diesel cdti, like the extra power & economy.
you could do a lot worse mate. they're a very decent engine.
 

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Discussion Starter #6
that doesn't make sense really? do you mean the compression ratio or the turbo's boost pressure level?
The compression ratio I think.




you could do a lot worse mate. they're a very decent engine.
I would agree, these engines seem to go forever if looked after. I've had my car 10 months & have changed the timing belt, water pump & thermo. I've had plenty of experience (diy), working on petrol engined cars, but not any on diesels. Only small grumble I have with my car is lack of power, but I new that before I bought it. Was just after something reliable at the time, which it has been (touch wood).

Thanks for the info.
 
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