3406b turbo upgrade???

Thanks, I will try that!
I have to really work it to get the EGTs that high, but on a long pull I have to watch it.

 

I always tried to keep ours under 925-950... with this truck, when egts start running there engine temps are 200+ with fan running almost none stop. So I would have to drop a gear and get boost up, and run much higher rpms...

 

Here you go @894964f :The supply line just barely misses.



@swaan , looks like I already put a washer in (I remember thinking about it but not doing it, hell to get old).

 

Thanks so much Oxbow.

What rpms do you operate in? Or anyone else that may know the hp/tq curves for best operational rpm?

This ol truck is pretty high geared, I think 75 mph I'm turning 1400 engine rpms(maybe 1500, will look next time I'm in it).

 

We have 4.10 rears so we are not long legged, but it works well for what we do.

When I am pulling hard I don't take it below 1500 unless I am about to top a hill, and the old timer in me likes to keep it higher than that, basically between 1800 and 1500.

With the 177148 it will pull well below 1500 without cavitating, and the engine feels like it is ok and wants to work there, but unless I am just idling along I don't like to run it that low. For highway use and short pulls I would guess pulling down to say 1200 for short durations and less than full throttle might be ok, but I just can't do it myself. The pyrometer will tell you when you are working it too slow.

@wore out ,@swaan , @spsauerland , I think you all have experience with what the rod bearings on B models look like at tear down, what do you guys recommend with a 177148?

 

You got it oxbow. Pyro will tell the whole story. If your engine is stock and not fueled up I wouldn't be afraid to lug it down to 1300. Especially with the 177148 as it works great at low rpm.

But I'd keep above 1500 if you got the screws laying in the tool box.

 

Seems like this engine with the old turbo felt like it wants to fight itself(vibration) if RPMs r much over 1650-1700 RPMs. Ive always just let it run where it is smoothest and egts/boost r middle of the road.
Interested to hear others experiences and what this model was designed to run at.
Thanks guys!

 

Here's my 6nz, long but the fitting to the block loos bigger.

 

Guys pretty well got it covered! B's like more RPM than a E. Cruising @ lower RPM is fine, but when working them RPM is your friend. The increase in the volume of air keeps temps @ bay and cuts down on piston and rod hammering. Once you get to an engine with one piece monotherm piston is when you can run some lower RPM. Lugging is hard on them.