TDI 300 Performance Mods

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jinglezdj

New Member
Posts
4
Hi there guys,

I have owned my L reg Discovery 300 TDI now for about a month, it had been in a little bump when I purchased her. But a new drivers wing later she is now sorted. I couldn't find just one alloy for sale, so I ended up buying a set of 4 ES alloy wheels in black so they have replaced the 3 silver ones.

Anyway I have performed the EGR removal with one of those kits, and also replaced the old intercooler hosing with some new stuff. Thinking of removing the cat, but I can't seem to find any threads that would show me how to get the best from doing these modifications. Could anybody point out a link to any thread containing such information as I don't really want to go to the lengths of doing these mods if they will not really make any difference in performance etc.

Also I have another question, I can move the diff lock lever from High to Low and this works, but if I move it into Diff Lock - High or Diff Lock Low 1. the light does not come on the dash, and 2. the diff lock doesn't seem to be on.

The box also wines when you go above 40mph even if you coast in neutral. Now the guy who I bought it off said that the gearbox had been changed about 6 months ago with a recon one. What do you think my problem could be? I looked at the thread regarding the mechanism seizing up, but I don't think that applies to my problem.

Being my first every Land Rover any help would be great.

Cheers,

Keith
 
Hiya, in my humble opinion, you've tried to address too many problems or issues in one post here, you'll never get answers to all of them. You're not gonna turn your Disco into a GTi either - chances are, from my experience, you can perk it up a little with a few simple mods all of which are very well documented within this site if you do a bit of searching...careful though cos you can accidentally lose an hour or three very easily...and end up thinking your car has loads od problems! It's like reading a home doctor book or googling life threatening diseases, you end up thinking you have the symptoms!:p Search out what you can and discuss gearbox probs seperately. That way future readers who have issues can search out individual posts...................as long as they're not entitled "Help" or "I have a problem" that is.:)
 
I don't mean to be all doom and gloom here, but let's be realistic for a minute.

That's say that with a bit of TLC you liberate an extra 10bhp from your motor. That's going to boost your bhp / ton figure by two parts of sod all.

In my opinion, all these little bits are all very well, but really don't make any differance. If your Disco is owt like mine, then what's on the clock will show that it has been to the moon and back, and that's if it hasn't been clocked at some point in it's life, (which I suspect many will have been by now).

Therefore your engines shagged, tired.

I personally think the best thing to do is take the motor out, strip it down and rebuild it properly. Port the exhaust manifold so it matches the head properly, stick some bigger valves in, a bigger intercooler, play with the fueling, new pistons and rings, replace what is likely to be a worn cam, etc, etc. Anything less is just ****ing in the wind, and it's what I'll be doing this winter.

As for the whining, I very strongly suggest that you pump in some fresh grease into the UJ's if your prop, and you go and do it right now.

Mine was doing the exact same thing, and take my word for it, you really, really don't want a prop snapping.
 
removing the cat will be a worthwhile mod, you may not gain any more bhp but the turbo will spool up quicker and the engine will feel more lively. I did mine with 170k on the clock and it made a load of difference and more economy too.

its dead easy to do just buy a defender downpipe (about 25quid) take off the original and replace with the new one, be careful of the nuts holding the downpipe to the manifold they have a habit of shearing off

re the whining, I would check all oil levels in gearbox and transfer box and and diffs, also make sure they are the right oils and as somebody else said grease and check all the propshaft joints

HTH
Dave
 
Thank you for the replies guys,

But just to add, I'm not looking to turn this into a 200BHP monster. I am just wondering that if these things are done to the vehicle would it be a good thing and is there anything else I need to think about such as fueling if I do this? I have seen somewhere, not sure if it was on this forum or another somebody had a thread which mentioned turning up the fueling from the pump and altering the wastegate when this was done.

Again as I am not yet a fully fledged Land Rover nut, I am looking to ask questions before I believe what I am reading etc if you understand. I run my own business modifying, tuning and servicing Subaru's, so I have a car which will give me performance when I want it. I'm just looking to get the best I can from the Disco, and also hopefully in return it will pull better when towing especially up hills.

As for the noise, I know it isn't prop related as I have already checked there. I will do an oil change on the gearbox and transfer box next week and see what happens then.

Thanks,

Keith
 
Perhaps I came across a bit too negative, and a bit arsey. My apologies.

Yes, I agree that doing any of these little bits is better than nothing, especially if the mods are cheap to carry out.

One cheap job that you could do is remove the inlet manifold and clean all the gunk out of it. When I did mine I reckon it was restricted by about 20%.

Maybe remove your rad and intercooler and give them a flush out? Replace your air filter with a new one and make sure that your airbox is as clean as a whistle, (I used a vac to get all the silt out of mine).

Remove your sedimeter, (located under the vehicle at the drivers side by the fuel tank), and give it a good clean out. Replace the fuel filter and check that none of the fuel lines are leaking. Remove the injectors and send them off to be flow tested and cleaned?

Check your wheel bearing. Check to see if any of the calipers are sticking.

That's about all I can think off ATM for free / cheap hp.


With regards to the props, did you just check to see if there was any movement in the UJ's, or did you pump new grease in as well?

Cheers.
 
Hi Keith, I agree with dave it's definitely worth fitting a decat front pipe. Did mine two weeks ago and it drives much better since. I can't comment on the mpg yet as I've not done enough mileage but I'm hoping this will also have improved. On my old defender I fitted a kenlow fan and this did improve performance.
 
Just my 2-cents on matters...

The 300tdi is not speed-demon, so don't expect it to be accelerating hard. What it does best is chew the klm's up, be miserly with the juice, be a solid n reliable unit, and put out sh*tloads of torque for towing. It won't do the stop-start stuff in gridlock particularly well, nor will it take a hill on a highway without shedding speed.

I have a '96 300tdi D1 with 255k klm's on the clock (but in immaculate condition, presentation and mechanically), and knew of what to expect from these rigs prior to purchase. They are supreme for hassle-free chewing of klm's and/or towing things, plus doing offroad work...nothing more. If you feel the need to tinker, here's the things which I'd be looking at given the nature of what goes on over your end of the world:

- Fixing any leaks on diffs, axle seals, etc.
- Greasing joints
- Flushing radiator (replace for a larger and ali-job if the pockets are deep enough but is unnecessary given the low temps and likely use of the Disco)
- Silicone hose replacement for coolant and turbo
- EGR blanking (we got that factory standard so is hard to comment on)
- Address any rust issues
- Fit a Safari snorkel (but do NOT fit a K&N filter)
- Full fluid change (Redline stuff for the gearbox esp)
- Fit breathers for the diffs
- Change tyres and suspension to suit your useage

...and above all, understand that there is no such thing as a perfect vehicle. Weigh up the purchase cost, amount of use and the likely (not intended means) of using this rig, what insurance you get with certain mods, practicality to you and your business, etc.

Personally, I'd get the bitch sorted properly mechanical-wise, and sort out any rust issues. If you keep ontop of maintenance (which it sounds you're in an ideal position to do so), you'll get yourself a rig which will last a very long time, put up with jaw-dropping abuse, and do everything you ask of it. The point-list above is some of what you should do, some of what is on the wish-list for all....it comes down to what you see as priority and feasable. ;)
 
Well as above really.
But with regaurds the Diff Lock. Mines a pain to get in sometimes you may have to really push the lever hard across a few times for it to engage. They dont get much use.
 
Well as above really.
But with regaurds the Diff Lock. Mines a pain to get in sometimes you may have to really push the lever hard across a few times for it to engage. They dont get much use.

Mines the same. If it goes some time without being used, it's a nightmare to use. Not so hard to get the transfer box into neutral, but really, really difficult to get it into 'gear'.

Have you tried putting the diff into neutral, bringing the clutch back up, then pressing the clutch back down and engaging the diff setting you require?

Do any if you chaps know what requires greasing in order to make the transfer box easier to use? Unless I have gone through each setting a few times, ours is so bad that the wife, (only a little lass), physicly can't use it.
 
Mines the same. If it goes some time without being used, it's a nightmare to use. Not so hard to get the transfer box into neutral, but really, really difficult to get it into 'gear'.

Have you tried putting the diff into neutral, bringing the clutch back up, then pressing the clutch back down and engaging the diff setting you require?

Do any if you chaps know what requires greasing in order to make the transfer box easier to use? Unless I have gone through each setting a few times, ours is so bad that the wife, (only a little lass), physicly can't use it.

I don't have this issue, but let the Disco roll back or forwards a fraction and try engaging diff-lock again...from what I've heard from others, this method works a treat. ;)
 
I have this problem on mine and rarely use the low ratio. Last time I used it lead to a few scary moments - it seemed to go back into high without a problem - that was until I pulled out on to the main road and lost drive!!

The last mm of travel on the transfer box lever makes all the difference.
 
Just my 2-cents on matters...

The 300tdi is not speed-demon, so don't expect it to be accelerating hard. What it does best is chew the klm's up, be miserly with the juice, be a solid n reliable unit, and put out sh*tloads of torque for towing. It won't do the stop-start stuff in gridlock particularly well, nor will it take a hill on a highway without shedding speed.

I have a '96 300tdi D1 with 255k klm's on the clock (but in immaculate condition, presentation and mechanically), and knew of what to expect from these rigs prior to purchase. They are supreme for hassle-free chewing of klm's and/or towing things, plus doing offroad work...nothing more. If you feel the need to tinker, here's the things which I'd be looking at given the nature of what goes on over your end of the world:

- Fixing any leaks on diffs, axle seals, etc.
- Greasing joints
- Flushing radiator (replace for a larger and ali-job if the pockets are deep enough but is unnecessary given the low temps and likely use of the Disco)
- Silicone hose replacement for coolant and turbo
- EGR blanking (we got that factory standard so is hard to comment on)
- Address any rust issues
- Fit a Safari snorkel (but do NOT fit a K&N filter)
- Full fluid change (Redline stuff for the gearbox esp)
- Fit breathers for the diffs
- Change tyres and suspension to suit your useage

...and above all, understand that there is no such thing as a perfect vehicle. Weigh up the purchase cost, amount of use and the likely (not intended means) of using this rig, what insurance you get with certain mods, practicality to you and your business, etc.

Personally, I'd get the bitch sorted properly mechanical-wise, and sort out any rust issues. If you keep ontop of maintenance (which it sounds you're in an ideal position to do so), you'll get yourself a rig which will last a very long time, put up with jaw-dropping abuse, and do everything you ask of it. The point-list above is some of what you should do, some of what is on the wish-list for all....it comes down to what you see as priority and feasable. ;)


Jut wanted to know why you say don't K&N air filter?
 
It's all mostly been said .. but I find that getting into diff-lock requires the vehicle to be moving .. you can knock it into difflock at any speed, but I find it's best done slowly, 10mph or lower and done using the clutch too, with a bit of throttle on and off.

It's also better to put it into difflock before encountering any difficulty .. if you get stuck it's probably to late to use it ... ;
 
I'm chewing through the wallet on my new 1994 disco 1 300tdi, i was resigned to crap performance until i fitted a boost gauge to the turbo and found i had no boost. £120 later and a 2nd hand turbo / manifold and i've got full boost and she will now accelerate uphil in 5th gear, its much more acceptable.

It does not affect pull-away though as the turbo does bugger all untill about 1800rpm with max boost at about 3000rpm. Its just in the right spot for grunt where you need it.

I also done full service, washed out intercooler and pipes, sedimentor, decat front pipe, and set the tappets. The tappets made a big boost in performance and the new downpipe lets it breathe better, you would not believe the crap that came out the back when i first started up after fitting it:eek: Its now running very clean, just a chuff on startup.
 
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