"tuned" profile fuel pins.

[Jon Wildsmith]

It's purely a guess, but last summer in Portugal, with ambient temps close to 40 c, much longer steep motorway climbs, much more weight in the truck, seeing how easily it got to 767, it was probably hitting 850, and maybe even higher. For short periods, every now and again, that may be ok, but probably not if you're doing it regularly or for longer bursts.

 

[Lorin]

Some data for the thread - first longer drive in my 80 after finally installing the EGT probe in the usual manifold spot just before the turbo. Easy cruising at around 60mph, EGT is around 400c. Easily hits 600c if there's a bit of a hill, 700c for bigger hills. Max EGT was 767c thrashing it up Birdlip which is hard work but short lived compared to some of those big hills it got thrashed up in France and Portugal last year. Ambient temps were around 5c. No intercooler. Stock turbo - boost maxes out at 10.5 psi. 3" exhaust. Boost compensator adjuster on the pump has been tinkered with by PO for sure but no way of knowing exactly what. Standard pin. Anti tamper collar still in place on max fuel screw.

Doesn't go too badly but likes to smoke at lower revs more than most so I suspect the low/no boost adjustments have been overdone.

So apart from the exhaust, engine is pretty stock, just someone played with the boost compensator which I don't think is doing a lot thrashing up a big hill at max boost?

I have an intercooler, fuel pin and boost controller to fit, but have been wanting to gather some EGT data first and get a feel for what's normal on stock ish setup before I make changes.

Not hard to see that just turning up the fuel a bit on this setup and hope for the best would make for some very high EGT's.

I fitted EGT about a year ago, same place in the manifold. I’ve a 3” exhaust but no pump tweaks. My numbers pretty much match. Highest I’ve seen is just under 1500f (~800c). Any climb in top gear with my foot down easily gets above 1300f (704c) usually hitting 1400-1450f (760-787c). These are just English hills, usually on a dual carriageway or motorway. Typically not that long duration or big incline, and air temps well below 20c. Nothing like the prolonged climbs of much greater incline I’ve done countless times in Europe (e.g. the Alps) many whilst pulling a trailer, and at times in temps of 35+ Celsius.

It would seem 1300f is a very conservative estimate of the safe limits for EGT. If the truck can be made to make good power with EGTs below this that can only be a good thing.