Upgrading 90 for more speed?

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Turboman said:
Going through it and finding what is limiting the performance might be the best idea. Filters, tappets, timing check etc.
200Tdi should be comfortable at 65, and top out 75 mph. Even my standard engine Ninety will cruise at 60, and get over 70 for a short time. Tdi produces 25 horse more than mine.
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Exactly this!

Oh and a 200tdi in good fettle is perfectly happy with a disco transfer box, acceleration suffers slightly but really it's hardly much. Other than that it's absolutely fine and will go up hills in 5th no problem.

Towing massive weights might be different setting off but if you don't do that no problem. I have first hand experience of a 90 with a tdi and disco box and normal defender tyres and it is fine.

Disco's are great, but let's face it, they aren't a defender which is waaaay cooler.
 
I don't quite see how a Disco transfer box will ruin the performance of a Defender.

Change it slightly, make towing slightly harder work but other wise they run the same engines/gearbox/diffs and Discos somehow manage.....despite being heavier.
 
blue beasty said:
I don't quite see how a Disco transfer box will ruin the performance of a Defender.

Change it slightly, make towing slightly harder work but other wise they run the same engines/gearbox/diffs and Discos somehow manage.....despite being heavier.
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Thats what you would think, but a 1.19 tfer box in mine killed what little power the thing had, 32 inch tyres though, I found fifth became an overdrive and hardly used, essentially I had a 4 speed defender.
Very very steep hill struggled to pull away empty uphill, back to std 1.4 lovely, still crap but bearable:D
Mate bought a 300 disco the other week, he followed me home at 70mph, up steepish hills he dropped back as lack of power, disco totally standard no tweaking etc.
 
Gottschalk said:
I take onboard about your point with tyre size, I have 265/75 r16's which are roughly the same rolling diameter as a 7.50 standard (tall) tyre
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Same rolling diameter, but a lot wider, which creates more rolling resistance.
One of the big problems with the many qs about performance is that they rarely provide tyre info. Very small will result in poor top speed. Very large and the older vehicles may not have enough power to drive top.
 
lynall said:
Thats what you would think, but a 1.19 tfer box in mine killed what little power the thing had, 32 inch tyres though, I found fifth became an overdrive and hardly used, essentially I had a 4 speed defender.
Very very steep hill struggled to pull away empty uphill, back to std 1.4 lovely, still crap but bearable:D
Mate bought a 300 disco the other week, he followed me home at 70mph, up steepish hills he dropped back as lack of power, disco totally standard no tweaking etc.
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Exactly. This is my point. On standard tyres with standard transfer boxes they run about the same rpm. But fit the Disco transfer box to a 90 with standard size 90 tyres and it'll usually kill the performance, as it'll be over geared. A good tweaked motor will pull it. But acceleration will suffer.

At speed a Disco has far superior aero dynamics than a 90. So should pull the higher speeds better.

My brother runs a 1.6:1 transfer box on his 200Tdi. It drives really well. It'll sit and cruise at about 60mph no probs. This gearing really wakes a Tdi up if you don't need to do lots of long distance.
 
300bhp/ton said:
Standard Defender should be fine tbh. Should happily sit at 65mph+

What transfer box and tyres size are you running? Also some LT-77's have a shorter 5th gear.

Swapping in a Disco transfer box is an option. But to be honest it'll probably kill the performance. Sure it'll lower cruising rpms. But acceleration will suffer. And if you haven't got enough power to pull the gearing, you'll end up using 4th where you used to use 5th.

For the record, a Disco running stock 28-29" tyres pulls about the same mph/1000rpm, as a Defender with 32" tyres.
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It is a military 2.5NA with standard box I only had the engine changed. It has the 16" skinny original wheels on. The engine is good and turbo working well. It accelerates fine but when it get to 50 mph it is flat and very noisey. Not road noise engine noise.
I don't need to fly around I appreciate it is a landy but for commuting to work or the small amount of motorway work I do I would like 60/65mph.
I sure my old b reg landy with 2.5 added on turbo went a lot better though?
 
By the way cheers to you all for the suggestions.
If anyone feels like tweeking the engine then feel free I am afraid, that is a little beyond me!
I know girls with landy's blah blah
 
I have a friend who has a overdrive unit, he tells me this would help? He normally does my tech mech work but he has no idea how one of these works.
Do you think this may help?
 
I've a 110 with 200tdi, disco transfer box, and 7.50 tyres. Using it to drive to work most days I'm very happy with the performance and quite happily sit at sixty . yes it won't take up hill in 5th at 30mph in town. But it will take a hill in 5th at 50. 5th becomes an overdrive gear, great for cruising at, 40 -70.
I do tow 3/4 ton of boat I've not found it a problem with the new gearing, yes you do change down more often but its a price I'm willing to pay having gone from 20 mpg and slow with a 2.5n/a to 32 mpg and keeping up with the traffic on open roads, I even occasionally over take cars.
On adding as much soundproofing as you can helps a 200tdi is a noisey old lump.
 
TheQ said:
I've a 110 with 200tdi, disco transfer box, and 7.50 tyres. Using it to drive to work most days I'm very happy with the performance and quite happily sit at sixty . yes it won't take up hill in 5th at 30mph in town. But it will take a hill in 5th at 50. 5th becomes an overdrive gear, great for cruising at, 40 -70.
I do tow 3/4 ton of boat I've not found it a problem with the new gearing, yes you do change down more often but its a price I'm willing to pay having gone from 20 mpg and slow with a 2.5n/a to 32 mpg and keeping up with the traffic on open roads, I even occasionally over take cars.
On adding as much soundproofing as you can helps a 200tdi is a noisey old lump.
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Hum, it just sounds like the lump is going to jump out in protest!
 
I still think there is something up with your engine.

I have the same setup as you even down to tyres and I can sit at 70 easily (genuine gps indicated 70)

It's noisy but that's due to the soft top and zero insulation.

I would be looking at timing, tappers, fuel injection pump, boost valve etc.

What exhaust do you have as if your running the original 2.5na exhaust it's too small and will strangle the turbo at higher speeds as it won't shift enough gas out
 
Oh and IMHO best box for the Defender is the 1:1.4.

1:1.6 gives great acceleration but runs out of rpm quick in every gear.

1:1.2 I wouldn't say kills performance but it certainly oh would be better if you don't tow and just endlessly sit on motorways.

1:1.4 best of both worlds.
 
Fattylewis said:
By the way cheers to you all for the suggestions.
If anyone feels like tweeking the engine then feel free I am afraid, that is a little beyond me!
I know girls with landy's blah blah
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If you are running out of engine rpms no amount of tweaking will help.
Have you got the std 3.54 diffs fitted?
 
flat said:
I still think there is something up with your engine.

I have the same setup as you even down to tyres and I can sit at 70 easily (genuine gps indicated 70)

It's noisy but that's due to the soft top and zero insulation.

I would be looking at timing, tappers, fuel injection pump, boost valve etc.

What exhaust do you have as if your running the original 2.5na exhaust it's too small and will strangle the turbo at higher speeds as it won't shift enough gas out
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Had a new section of exhaust from manifold, same mid section and left out rear box welded straight through.
 
Fattylewis said:
I have no idea I assume originals unless military changed them?
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I doubt they would be changed, but who knows what has happened in the past?

When I fitted a tdi to my series 2 it would do 60mph flat out absolute max rpms, that was with std 4.7 diffs, it now has later 3.54 diffs and cruises at 60 mph with no dramas, will go quite a bit faster, this is a standard 200 with standard injector pump settings.
 
Fattylewis said:
By the way cheers to you all for the suggestions.
If anyone feels like tweeking the engine then feel free I am afraid, that is a little beyond me!
I know girls with landy's blah blah
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I wasn't suggesting tweeking anything, just the usual diesel things, filters, tappet clearances, injector and pump condition and timing! :)

tottot said:
This thread is much of a contradiction Land rover/ speed;)
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Yes, the two don't really go together, but this ladies vehicle does seem exceptionally slow! :)
 
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