Thread: Slow Disco

Thanks to all. I know I sound dense, but all my experience is with old, non turbo
diesels, petrol engines and my TD5.

I'm really enjoying driving the 300 Disco. It's not as fancy as the D2, but that's not a bad thing. I just miss the power.

Anyway, it has Maxi Drive axles and rear locker, Maxi Drive reduction gears in the T/C and an Ashcroft suffix L R380 with less than 10K and near new Maxxis 265/75/16
Bighorn 764's on it, so I've bought it, and I want it to run right, so i'll be slowly doing things and asking annoying questions about it.

So, Timing belt and oil seals, lash caps, clean out the rad ( gets warm on longer trips, fine otherwise. Oh, it also has a temp alert and an EGT display ) and maybe a bigger intercooler while it's apart.

Hmm, all that plus replacing a few stumps on the house and taking the head off the TD5 and replacing the guttering.... while driving to Brisbane and back each week. Could be worse.

Full throttle helps as well!

Dragging this one out of the vault. Thought I'd report back. Didn't get a lot done until mid this year, due to work. But now I have done the head gasket, timing belt etc. Last week I replaced the turbo core with an upgraded one, and adjusted the max fuel screw in about a 1/4 turn. Wow. I have not done the star wheel diaphragm mod, the intercooler is the standard one and the exhaust has the centre resonator removed. It is now a different car. It starts to pull from around 1500, I am using at least one higher gear in most situations and I no longer have a queue behind me on hills.
I do notice one thing though. On a long climb at full noise the EGT will spike a to 720 (before the turbo). If I back off a touch it drops back. I have read that this is ok, but what do you guys think?
Going to fit a boost gauge so I can check what's going on there before I do anything else. Another hundred k's to go before the diff is run in and then it's a long drive.

Hi, if you have bigger than standard wheels that 720 EGT is acceptable, even with standard wheels if the hill is well inclined

Hmmm, not sure what tyre size has to do with acceptable EGT levels. I regard 720 C as the most you ever want to see and then only rarely. I begin to ease off slightly at 700 C. As you will have noticed, it requires only easing off the loud pedal just a couple of mm to stop EGT rising - no need to really lift off the throttle.

Tyre size has to do very much with the EGT, ECT and transmission temp as well, i'm not gonna keep the whole theory, check yourself, put 10% bigger tyres and drive it as usual and compare with how it was with the smaller or standard tyres...all i did on mine was to fit 4% bigger than std tyres(255/70/16) and the EGT got higher at full load uphill with up to 150*C peaking to 700(rarely got 600 before more loaded), the gear stick and central console got hot and ECT above 100*C with the same driving style and same ambient temp

I never said larger tyres have no effect on EGT or any other factors. Larger tyres or anything else that increases the load on the engine (such as towing a trailer or caravan) will cause EGT to rise faster and probably higher if you keep you foot flat to the floor.
(Although the maximum level that EGT will ever get to is determined by the maximum fuel delivery of the injection pump. If you never want it to get beyond reasonable levels despite the driver keeping the throttle floored, just back off the maximum delivery until it never exceeds your chosen limit on a hot day and heavy load.)
I simply said (and I stand by it) that tyre size (or towed loads, steepness of hills etc.) plays no part if determining what maximum level of EGT you are prepared to accept. By your logic, even bigger tyres would make 780 C "acceptable"??

Almost Yes is my answer to your last question, IMO(in my logic) it's not about how acceptable it is but about how much you overload the engine so if you insist you can get even 900*C EGT from a well working management.... the cure is to not put so big tyres or overload the engine so as to make the EGT unacceptable, hence my statement for the OP about tyre dimensions which intrigued you.... though i dont want to argue on this, i've just said what happened to me in real life and IMHO it has plenty of logic.

if you "attack" a long and steep hill with huge tyres and you want to decrease the EGT by releasing the throttle you might not get to the other side whatsoever

Originally Posted by Leo109

..... Although the maximum level that EGT will ever get to is determined by the maximum fuel delivery of the injection pump.....

a.a.m.o.f..... the Td5 doesnt have an injection pump, it's a different kind of engine