Thunderbolts Way & TD5 lack of power on hills.

[timax]

So over the years i have read quite a bit on what to check or replace with TD5's.
My car has an auto conversion and is a 2001 TD5 110. Along the flats is plenty quick enough but this last weekend i found some of the big hills to really be a struggle. No more than usual but i just started dreaming of Toyo V8s!! [bigsad] For anyone who knows Thunderbolt Way i was down to 35kph with my foot to the floor in some parts. Nanocom was reading 120 on the turbo boost and coolant hit 100 before i backed off and got the heater cranking to help cool it down.
So car has basically a new MAF with no change to power....fixed leaking fuel pressure regulator also for no change and a EGR valve delete and K&N filter likewise.
No diesel in the oil and i always use a little fuel injector liquid moly conditioner. Engine runs nice an smooth but just hates hills.
So whats next to check? Im thinking an intercooler clean as i have never done that despite replacing the hoses with silicone.
Car has 180k on it. Would a dirty intercooler really make that much difference? Is this just normal for a TD5? Its the only one i have driven so nothing to compare to.

[djam1]

I have no idea how a TD5 Defender converted to auto would perform but the Discovery the only auto TD5 ran more boost than the Defender.
You could up the boost as it sounds you are only running 1.2 bar but if you go too far you will end up with an overboost situation.
I guess the other question is what transfer case ratios you are running?

Id check it out and make sure there is nothing wrong (no errors in the ECU) and maybe invest in a remap. But as the car is a 2001 it would of originally had a MSB ecu that couldn't be programmed without physical intervention.
BUT the question is what did they do when they did the conversion maybe it has an NNN ECU

Not sure what Jose (TD5inside) could do for you he may be able to send you another ECU if it is an MSB or a remap if it is a NNN the next step would be another intercooler and if you want to spend a bit more try one of his hybrid turbos.

Don't know anything about the road you mentioned but either its hideous or the car is a lot worse than any TD5 I have driven

[Tins]

A bit out of left field, but have you had the auto, and more particularly, the torque convertor checked? I can't speak for a Defender, but there is no way my Disco would be doing what you describe. Thunderbolt's can be steep, but not that steep, and TD5s go well when on boost.

[timax]

Transfer case is a Disco one-No errors on Nanocom and the ECU is original with the 4HP22 being rebuilt 1 year ago and cable operated.
Fuel pump isnt noisy but is another thing im thinking about.
Mooney Mooney bridge and the Orimba hill on the Newcastle/Sydney freeway are also terrible with speeds down to 75 or 80 if i dont hit them at about 120.
Typical for me is to be in the right lane over the bridge at 120+ then cut across 3 lanes to the slow lane part way up the hill.
Im a bit over doing that and would love to just sit at 110 no matter what. This is next to no load also

[djam1]

What size tyres?

[Tins]

Transfer case is a Disco one-No errors on Nanocom and the ECU is original with the 4HP22 being rebuilt 1 year ago and cable operated.
Fuel pump isnt noisy but is another thing im thinking about.
Mooney Mooney bridge and the Orimba hill on the Newcastle/Sydney freeway are also terrible with speeds down to 75 or 80 if i dont hit them at about 120.
Typical for me is to be in the right lane over the bridge at 120+ then cut across 3 lanes to the slow lane part way up the hill.
Im a bit over doing that and would love to just sit at 110 no matter what. This is next to no load also

Strewth. I could almost beat you up there in the Scania.. Definitely something wrong IMO. Still, at least you don't have to worry about the wet weather speed cameras.

[rick130]

Stock engine and 235/85's?

It's overgeared with the 1.2:1 t/case IMO.

IIRC I was able to maintain 105km/h coming south up out of Mooney Mooney with an absolutely bog stock D2 fully loaded up from three weeks out west and a roof top tent as a parachute!

[Colmoore]

Yep something's def wrong. The first time I drove a td5 was about 10 years ago. A mate of mine, who is horrible to any car he drives, had a 130 td5 with an old Telstra steel work back full of tools on it, weighing in at 1.4t. We surfed at Myponga (in SA) and I drove it back to Goolwa - pulled 110km/hr up that dirt track which is really steep. Kept going like a train on the rest of the hills but I backed off a bit when I realised the 'tail wagging' wasn't due to the loose dirt road but was actually very worn rear suspension/yoke components [emoji51]

[timax]

Stock engine and 235/85's?

It's overgeared with the 1.2:1 t/case IMO.

IIRC I was able to maintain 105km/h coming south up out of Mooney Mooney with an absolutely bog stock D2 fully loaded up from three weeks out west and a roof top tent as a parachute!

Interesting , i thought the Disco transfer case was the thing to have? Oh and yes stock wheels and tyres. I cant remember the rpm at 100kph but might check back with that info.
Changing down a gear though just makes more noise not a surge of power

[Colmoore]

Does it have a cat converter?

[timax]

No cat and no center.

[mrb505]

A bit out of left field, but have you had the auto, and more particularly, the torque convertor checked? I can't speak for a Defender, but there is no way my Disco would be doing what you describe. Thunderbolt's can be steep, but not that steep, and TD5s go well when on boost.

Not that steep ! What road are you comparing it to.

[djam1]

If you look at the Ashcroft transmission ratio calculator for a Defender with Disco auto and transfer case and 235/85 16 tyres this is what you get

35 kmh at the top of a hill looks pretty sad

High First Second Third Fourth
10 KPH 701 418 283 206
20 KPH 1402 837 565 411
30 KPH 2103 1255 848 617
40 KPH 2803 1673 1130 823
50 KPH 3504 2091 1413 1029
60 KPH 4205 2510 1696 1234
70 KPH 4906 2928 1978 1440
80 KPH 5 607 3346 2261 1646
90 KPH 6 308 3764 2543 1852
100 KPH 7009 4182 2826 2057
110 KPH 7709 4601 3109 2263
120 KPH 8410 5019 3391 2469

[timax]

Thanks all for your help.
I now feel all is fine with my engine and its just the high gear ratio.
I love it along the flats and its fine off road or at lower speeds just not trying to maintain 110 on hills.Plan now is to fine tune my kickdown a little earlier or higher in the rev range as its now at about 1700 rpm which is lower than peak torque.
Oh and the section of Thunderbolts i was having problems with was from the river at Bretti to Carsons lookout which is about 16 or so K's and climbs near 1k.
Some parts steep and the box in "D" would drop down and then change back up , drop down and back up.......I know i should have just changed it manually but hey i did 10 hours behind the wheel that day on 5 hours sleep including the Oxley highway in the fog and rain at night! EPIC drive and loved every second.