Straight Through Exhaust

Hi There

A few months back I brought a 53' Freelander TD4... and I recently saw 'the famous four' 4x4 company advertising a straight through sports exhaust for the TD4 Freelander...

Any thoughts reguarding..

MOT?
Emmisions increase?
Power increase?
Fuel reduction?
Noise?

And you want to do this because.....?

Bit more power, bit more noise...

Oh, I see. I don't know what difference it would make to the performance, in fact it might make it worse if the back pressure is upset. Might be a case of try it and see. Report back if you do and let us know your findings. Never considered putting a bad boy exhaust on a TD4, a V6 maybe.

hazz-101 said:

Hi There

A few months back I brought a 53' Freelander TD4... and I recently saw 'the famous four' 4x4 company advertising a straight through sports exhaust for the TD4 Freelander...

Click to expand...

which bit's straight through ? is it a simple de-cat pipe, or does it replace the one and only silencer on the rear of the vehicle ?

Heres the description...

Famous Four - New Parts for Freelander 1998-2006 Models - Exhaust

Darmain said:

in fact it might make it worse if the back pressure is upset. .

Click to expand...

not strictly true!
a turbocharged engine doesnt work on the same overlap/backpressure principles as a naturally aspiated vehicle! if it has a turbo, the less backpressure the better, this is because the vast amounts of air being compressed by the turbocharger, cannot be evacuated as efficiently as a nasp, therefore, there will ALWAYS be more backpressure than required! hope that makes sense?

the fuel efficiency of an TD engine normally increases when a low resistance exhaust system is used as the turbocharger can spin up quicker as it is not having to fight backpressure this is of course as long as it is driven in an economical manner but as it normally gives a 'sportier' note to the exhaust people drive the vehicle harder so the effects are negated.

as a case point one of my best mates has a scooby with a prodrive cat back system and a de-cat pipe, when driven normally this gives increased economy to the tune of 4-5 mpg it also gives approx 25bhp increase at the top end of the revs and a much smoother quicker turbo response

Spot-on G-man.

Not long ago removed EGR, replaced all turbo/intercooler/air inlet pipes and added a de-cat exhaust. The difference when driven steadily is an increase in mpg by ~5mpg. However, it feels so nice to drive now that sporty style driving (Sporty in a Disco ... ) is much, much more fun but drops fuel consumption by about the same ...

Towing the caravan is vastly improved, as is hill-climbing, and general drvieability.

Driven slowly to conserve fuel it's still at least as good (fast) if not better than it was before the swaps.

as i said then!

Cheers chaps

Im still a little confused about where i stand with the MOT? Will i be failed for a straight through exhaust?

+ If TD engines run better with a straight through exhaust, then why does mine have two silencers as standard?

to silence it! not everybody wants a loud car, and most if prefer to travel in relative quiet! all cars are a compromise between performance and comfort!

Ahh, at my age 'bring on the noise'

im only 31
and this WAS my other love, so i can assure you i do enjoy a bit of performance and the discomforts that come with it