Disco 1 300tdi top speed 68mph????

Hi, i own a disco 1 300 tdi when i bought it a couple of months back it would quite hapily do 80 to 85. it has seemed a bit slugish lately and will now only do just under 70. I have replaced the lift pump, fuel filter intercooler pipes, cleaned the sediment trap, replaced air filter with a K&N, Blanked EGR, checked turbo end float and it seems to boost well. Was thinking pump timing maybe? Any ideas was hoping someone maybe able to shed some light.

Many thanks
Potts

Check the speedometer

Yeah thought about that i was following a mate who said he did'nt go over 70. I have fitted some slghtly bigger tyres recently but i would'nt of thought the would make that much difference.

Tweak the fuel pump..
I get over 100mph on my 300tdi and it pulls through the gears well.
Only mod is bigger intercooler (from an saab), mondeo radiator with electric fan, fuel pump tweak and boost tweak.
Do a search on here there is loads of good info on how to adjust the fuelling.

Thanks i will have a look, Just seems strange how its just gone this way recently.

Take it out of low range and get a v8

ice said:

Tweak the fuel pump..
I get over 100mph on my 300tdi and it pulls through the gears well.
Only mod is bigger intercooler (from an saab), mondeo radiator with electric fan, fuel pump tweak and boost tweak.
Do a search on here there is loads of good info on how to adjust the fuelling.

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That takes guts to drive a d1 at 100mph!

biolandy said:

That takes guts to drive a d1 at 100mph!

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Ive hit a 117mph in Disco1...........wasnt a poxy diesel though...

Anyone who's taken a Disco over 85mph is a fookin nutter, they shake like mad due to serious lack of aerodynamics! As to the OP, one of your recent mods has obviously altered performance ... check each one for a problem.

biolandy said:

That takes guts to drive a d1 at 100mph!

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I've actually had an indicated 115 mph out of the fooker.
Dunno what that it is real terms, speedo's tend to always overread, have yet to test it with my satnav.
Private roads only obviously...
Anyway it's in bits now for more upgrades this winter.

Ported cylinder head, big oil cooler and freshen up for the motor.

Lots of new metal for the body!!!

Ice, you've gotta death wish

Dewin said:

Anyone who's taken a Disco over 85mph is a fookin nutter, they shake like mad due to serious lack of aerodynamics! As to the OP, one of your recent mods has obviously altered performance ... check each one for a problem.

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They only shake like mad when the body mounts have rusted so badly that the rust is holding the body t the chassis!!!

my old 2 door rangie with an up to date drive train did 120....

that was atchuall very scary and wrong despite it being stable at that speed.

a good clean 300tdi ought do 120.

Beast o Bodmin said:

my old 2 door rangie with an up to date drive train did 120....

that was atchuall very scary and wrong despite it being stable at that speed.

a good clean 300tdi ought do 120.

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Bob is talking km/h.

storm99 said:

Bob is talking km/h.

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:hysterically_laughi:hysterically_laughi:hysterically_laughi:hysterically_laughi

ice said:

Tweak the fuel pump..
I get over 100mph on my 300tdi and it pulls through the gears well.
Only mod is bigger intercooler (from an saab), mondeo radiator with electric fan, fuel pump tweak and boost tweak.
Do a search on here there is loads of good info on how to adjust the fuelling.

Click to expand...

Which Saab is it from? Was it a straight replacement for the original or did you have to do some engineering?

Beast o Bodmin said:

my old 2 door rangie with an up to date drive train did 120....

that was atchuall very scary and wrong despite it being stable at that speed.

a good clean 300tdi ought do 120.

Click to expand...

ave you fixed your engine yet ?

Check the Catalytic converter. My 300 tdi was slugglish and low on power until i replaced the cat with a De cat pipe. Suddenly it went like a scolded cat (excuse the pun)
Land Rover Discovery 300 Tdi DeCat Cat Removal Pipe on eBay (end time 03-Jan-11 19:05:04 GMT)

Tried to paste a link.

For the cost of the pipe, it is well worth trying.

Richard Martin said:

Which Saab is it from? Was it a straight replacement for the original or did you have to do some engineering?

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I used have a saab 900 turbo IC fitted. A few mods to the hose and it worked fine.
It's still quite small though.

Now I have a saab 9000 turbo IC fitted. Much better and bigger.
As I have a mondeo radiator and electic fan, the big intercooler sits in front behind the grill.
Some fabrication but not much.
Made a cross bar and mount for the IC and some custom pipe work.

After the winter the next intercooler will be double the width of the saab one.

Mission---- to get 200hp from a 300 tdi

Thank you all for your help, will try a de cat pipe was looking at it earlier it has a stainless exhaust but the cat is still there so i am ordering a de cat now. Does anyone think that the bigger tyres i have fitted may effect it as the rolling radius is much bigger?