RRC 300tdi R380 conversion complete but need advice?

[punkinracer]

Ok so I'm hoping that someone with some ideas will chime in here (red90?)!!

Some background, 92 Lwb range rover 300tdi, r380 with lt230 fitted. 4.43 Gbr gears fitted with 35" tires. Ailsport inter cooler and tweeked the pump. No turbo mods and only tweeked the pump with the smoke screw, diafram and star wheel.

So the truck runs and drives awesome around town and pulls like a train. On the highway is another story, have it nearly floored at about 2100rpm to get 100kmph out of it, 6-8psi on the flat but full 15psi on the slightest hill. Watching the EGT gauge more than the speedo!

Ideally I would like to cruise at 110kmph or so and not have my foot cramp or worry about the engine. Am I expecting too much here or did I go to far with the mods?

Thanks in advance
Pat

[red90]

No idea really. You should be able to cruise all day at 120, on the flats with no head wind. You've verified speed by GPS? 1.2 transfer case gears? Can you go faster in 4th? Any idea which R380? There are some different ratios?

What are the max EGTs? How is the smoke?

[punkinracer]

Hey Red, not sure which ratio the r380 is, apearantly it was out of a UK 98 300tdi disco. I'll check the numbers and get back. EGT will sit around 700 on the highway at 2100rpm 5-8psi. Climbs fast at full 15psi and I have not taken it 950. Transfer case I believe is 1.2, out of the same disco. I have a couple so I will run the serial numbers. Rpms are based off the stock v8 gauge running off the tdi alternator, seems reasonably accurate. Speed is based on gps as the speedo is way out. No smoke whatsoever while driving, just a little on start up.

I'm not sure what a normal 300tdi is like so I have nothing to compare it too. Pulls like crazy up to 1900-2000 then seems to strain there after, no sputters, just kind of boggy. One thing I should mention is I'm still running the stock v8 exhaust as it was fairly new, no cat though. I may pull the first muffler out and see what that is like. Unless it is a fuel issue. I pulled the gas fuel pump assembly out of the tank and swapped the pump out for a piece of pipe. For some reason I kept the v8 filter at the back, and the standard spin on tdi filter is at the front. Maybe it's starving??
I'll check the serial numbers and report back

Thanks for your help
Pat

[Whistler110]

My Disco with a Mercedes diesel conversion suffered fuel starvation caused by the frame mounted V8 filter. I bought a new one, it's a cheap GM filter, drilled it out and installed it. The starvation problem went away.

My fuel starvation was obvious though, complete loss of power and sputtering going up hills with the pedal floored.

[red90]

Are you sure the tach is reading right? A TDI should start to pull hard at 2000 rpm and then pull strong into the mid 3000s. What is you engine speed at vehicle speed? It does not sound right at all.

950 F is really low, unless you are talking celsius. You can sit at 1250 F for the rest of time. If it is not going above 950, the fueling is way down and I would suggest turning up the main fueling screw. Just do small amounts and keep track of exactly what was done, so it can be reversed.

Get the transfer case and gearbox serial numbers and we can figure out your actaul rpm versus speed and see what is happening.

[punkinracer]

EGT temps are in F, so do those temps sound cold? I will pull out the v8 filter as it likely will cause problems later on, pain to get to anyway! RPm feels right, but not sure, can't be out by much if it is at all.

R380 # 55A9373788J LT230 is # 28D419426E (A3 above #) I've got another 230 with #28D537567F (E3 above #) in the shop.

The trucks also got 4.43 diffs and 315/75/16 tires.

Thanks,
Pat

[red90]

So 0.77 * 1.222 * 4.43 = 4.17 final drive. 375 rev/km on that tire or 1563 engine revs per km. Should be 2600 rpm at 100 km/h. 3000 rpm is 115 km/h.

Boost and torque should come on strong at 2000 rpm or so and pull hard from there up. As above, check the fuel supply. Check that the lift pump is working and the fuel filter is clean (and a proper one for the engine).

On the EGTs, you have a lot more to go if you want.

[red90]

R380 # 55A9373788J LT230 is # 28D419426E (A3 above #) I've got another 230 with #28D537567F (E3 above #) in the shop.

55A is a Disco 300TDI box, 0.77:1 5th gear. 28D is a Disco 1 t. case, 1.222:1 high range.

[punkinracer]

thanks red, thinking that the tach is actually out a lot according to your numbers. Might have under geared it a bit. I'll go through the fuel system in the next few days ad see how that goes. Tried to get a new fuel filter at Lordco and they looked at me all stupid! They don't recognize the britpart number.

Thanks again for your help
Pat

[red90]

The TDI filter: BOSCH 1 457 434 106

Any 77 to 84 VW Diesel should be the right one, IIRC.

[red90]

Disconnect the discharge line from the lift pump and stick in a bucket. Pull the wire from the injection pump and crank it over. You should get lots of flow. Lift pumps have a high failure rate.

[punkinracer]

I removed the "v8" fuel filter and things seemed to have improved. The engine Rpms and tach still don't seem to match very well, 2200 in forth sound a lot differant than 2200 in fifth. I'm going to try to swap to a Hall effect crank sensor and see if that changes things.

[red90]

What tach do you have and what is it connected to? You should be able to connect to the alternator and always get a clean signal.

[punkinracer]

I've got the stock Range Rover tach connected to the 300tdi altenator, and it seems to function correctly. Just the sound of the engine revs sound a lot different and the same gauge rpm in fourth and fifth gears.
Pat

[red90]

Oh, I see. You need a converter to adjust the signal as the tach is not adjustable, like this: http://www.dakotadigital.com/index.cfm/ ... prd238.htm

You can figure out what the rpm should be at any speed and gear. The only way it will be right in one gear and wrong in another is if the belt is slipping.

[punkinracer]

Holy crap, they actually make something like that! That will save so much time, thanks again Red!
Pat

[red90]

Yes, there are lots of different ones out there. Google to find a decent price and to make sure it works with both ends.

This is probably a better choice: http://www.dakotadigital.com/index.cfm/ ... prd128.htm