COA

New Member
My 90's top speed is around 60 mph. If I wanted to go faster like 70 or 75 what items would I need to check and what should I start with / most likley to make the most difference?

Its a 1985 CSW converted from petrol to a 200 tdi and they changed the gears over at the time of conversion. The conversion was a while back.

Please lets not get into a debate as to why I go faster and why dont I buy a ferrari....etc (yawn)
 
Disco transfer box.. Do you want to cruise better on the motorway, or want more power from the engine? (acceleration....)
 
mine does 75, all you need to check is the car behind to see if they can still see out their windscreen!!
 
My sense is that there should be more grunt. I am wondering if cleaning out the intercooler would help or do I need to check that the accelerator pedal is opening the throttle as fully as it goes.

I am looking for things that an idiot can go do in his garage rather than dig up weeds.....its a slow day at work....ok:)
 
I would start with the obvious first, is the throttle pedal getting full throttle on the pump?
My series 2 tdi with defender 3.54 diffs same as yours but no overdrive will do over 70, at the weekend i clocked it on the gps at 74.8 mph on a slight downhill stretch and that doesnt get full throttle on the pump theres another 2mm or so to go.
So if my s2 can do it so should yours.
What speed does it do in each gear?


Lynall
 
Lynall - thanks for that suggestion, I am assuming that to test this I simply push the accelerator to the floor and look at whether the cable pulls the throttle fully open? If it does not then I make the necessary adjustment to the cable - but will that affect the idle / tickover?

I am not sure what speed I get in each gear but I know that I typically change up from 4th to 5th at around 40 or 45 mph and that fifth takes me to 60. I am sure that if I was going down a hill and gave it 100% I might make 70 at a real push. It can sit at 60 but doesnt really want to go any higher than that and I reckon I am using 85% throtle in 5th gear to get 60mph.

So apart from checking the throttle - what else is easy to check with a spanner (i'm not calling myself a spanner you understand)..

Thanks
 
If you can only hit 60, I'd say there's something up. Mine will hit 90 no problem but I wouldn't keep it at that speed. 60-70 is what you'll have to settle for. Faster than that they are so unstable it's literally dangerous and the fuel consumption makes you want to cry.
 
Lynall - thanks for that suggestion, I am assuming that to test this I simply push the accelerator to the floor and look at whether the cable pulls the throttle fully open? If it does not then I make the necessary adjustment to the cable - but will that affect the idle / tickover?

I am not sure what speed I get in each gear but I know that I typically change up from 4th to 5th at around 40 or 45 mph and that fifth takes me to 60. I am sure that if I was going down a hill and gave it 100% I might make 70 at a real push. It can sit at 60 but doesnt really want to go any higher than that and I reckon I am using 85% throtle in 5th gear to get 60mph.

So apart from checking the throttle - what else is easy to check with a spanner (i'm not calling myself a spanner you understand)..

Thanks

I can change to 5th at about 40 and get to 90.
 
Yes engine switched off, pedal to the metal and see if the pump lever is reaching its stop.
To adjust theres a knurled nut on the pump end of the cable, make sure you leave a a little slack and it wont effect tickover etc.


Lynall
 
you should be cruising at 65/70 with a 200tdi

can you here the turbo whistle

changed ya air/ fuel filters lately

what mpg are you getting

sumuts wrong..
 
COA
I know it's easy to say..but do a good search on this topic...I am not being arsey. It's just there is so many different things to check. Start with doing a full service.. Oils, filters etc.. Check the turbo is working, check intercooler is clean and hoses are not collapsed. Check no oil in the top of the fuel injection pump stopping the diaphragm working. Check the small hose to the injection pump. My 200 tdi could hardly hit 50 when I bought it 5 months ago. It now gets to 75 (with the help of fuel injection pump tweaks.....another search required) it's gives you great sense of achievement when you do all these things and it works.
 
Saxman - perfect - that is exactly what I was looking for. It gives me some idea of what to go research on this site. Doing a search for "going faster" leads you down a path that could take 20 hours of reading to digest!

Lynall - great help, I did that and it makes a difference!

Thanks
 
My 90 was like yours before I started playing with it, sluggish off the line, no go in any of the gears and although it would get up to 70 on a run it really wasn't happy and needed the throttle right down to stay there. I completely rebuilt mine over the winter and spent quite a lot of time and money getting it as quick as it is now. Now it will spin all four wheels if I really give it the beans out of a junction, pulls really well through all the gears and will hit 90 on the clock before the noise and general instability scares me enough to back off.

It's a 1991 Defender 200tdi with the standard LT77/transfer box and 235/85 mud tyres. So far I have done:

Cleaned and flushed the intercooler
Pipercross cone air filter
Terrafirma silicone turbo hoses
Terrafirma straight through stainless centre pipe
Made my own (also straight through) side exit exhaust that comes out of the rear quarter.
Fitted a boost gauge and raised the boost on the (standard) turbo to 1.2 bar
Adjusted the main diesel screw on the back of the IP in approx 3 turns.
Removed the viscous fan and fitted an electric fan set up I made myself out of bits.
Also what may help is I've replaced all the prop ujs, brake discs and pads, handbrake shoes, both rear brake calipers and all the diff and gearbox oils so there's nothing dragging or binding anywhere.

You will find with the adjustment on the pump there's a lot more you can do internally, however I've had good results just from winding in the main screw on the back. It's noticeably faster as a result just from that although I now get a puff of black smoke on start up where it was perfectly clear before, but I can live with that :)

I'll post some pictures up later if anyone's interested.
 
Pics would be good fella. Mate has a 300tdi that he wants abit more out of and I will out if my 200once I'm used to the power compared to the td!
 

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