Pulling behind other trucks

[Running rough]

Followed a Mack pulling a superb Gibson oil tanker loaded, am guessing it's powered by the 13 litre mp10 Mack engine, not sure on what hp and torque spec but that thing defiantly not a power house, if the paccar mx13 is anything like it, then I can see why a 15 litre is a man while a 13 litre is a boy, lol

[Rig Wrench]

(01-10-2017 )Running rough Wrote:  Followed a Mack pulling a superb Gibson oil tanker loaded, am guessing it's powered by the 13 litre mp10 Mack engine, not sure on what hp and torque spec but that thing defiantly not a power house, if the paccar mx13 is anything like it, then I can see why a 15 litre is a man while a 13 litre is a boy, lol

Mp8 is the 13 liter class. Mp10 is 16 liter. Mp8 is a horrendous pos. Only ever drove 1(had an m drive coincidentally) that was worth a chit. Unless it was a Titan, I highly doubt it had the mp10. The paccar is far better in my opinion

[Running rough]

Sorry my bad, yes I ment the mp8, I talked to the boss at a local truck wreaker used parts ect., and asked him if the hype is true, that the paccar mx is a low rpm engine, and pulls like a cat, he told me, bunch of ballony, it doesn't pull anywhere near as good as a simuler hp cat and that the isx is still a far better choice for a power plant, despite its well known issues

[Rig Wrench]

(01-10-2017 )Running rough Wrote:  Sorry my bad, yes I ment the mp8, I talked to the boss at a local truck wreaker used parts ect., and asked him if the hype is true, that the paccar mx is a low rpm engine, and pulls like a cat, he told me, bunch of ballony, it doesn't pull anywhere near as good as a simuler hp cat and that the isx is still a far better choice for a power plant, despite its well known issues

Between the paccar or Volvo/mack. I'd still take the Paccar

[Running rough]

Paccar trucks I would definitely pick, but I have no experience with either the mx or Volvo, but if the paccar engines stand up better then isx15s in car hauling, that does not make the isx look good,

[Running rough]

....but to be fair cm2250 with 871 turbo, @m*m^2 style tuning by Unilevers not quite sure where he's got the power set at but it is totally badarse..., this thing builds better torque then your beloved c16 even at low rpm, probly get him to set it to something more reasnable down the road, can't afford to experiment with a $40000 boat anchor

[Rig Wrench]

The 2 2250s with he551 turbos I did do real well. One needs a bit more tweaking. I think it helps tem hold up better. The engine breathes much better up top, less back pressure. These are both running in the 40psi area of boost. No failures at a constant 100k+lbs. Definitely a sweet setup for that engine. Throw in a 5 inch downpipe and clean up the intake manifold and it gets even better

[Running rough]

Yes it defiantly moves more air then the stock turbo, I noticed my oil temps are slightly cooler with the 871 turbo to, probly due to it not have to work as hard and spin as fast, definitely more higher and midrange power, however you can still feel the torque rise as rpms come down under 1400 in a pull, not sure if it is his tune or just the 2250 inherit ability to make tighter torque as when compared to say a 871 or 870, granted stock they are notting special (the 2250 I mean, cummins stock Cals are kind of droopy on lower rpm torque but their 2050 torque stock tune is a lot better then thier 1850, there are more gains to be had if u go the @m*m^2 rout, with mpg torque response ect, if you choose to keep the stock turbo, my opinion, it is good for 2050 torque and 600 hp max, it probly will not quite make u 600 hp but it will make u 2050 lbs in the lower rpms, that's my experience, but it does not light a candle to what uni has in my truck now with the bigger turbo,

[Rawze]

(01-11-2017 )Rig Wrench Wrote:  ...
These are both running in the 40psi area of boost
...

Have that boost lowered to around 36 and they will run better. 40 is too much boost for a 2250, i don't care what turbo you have on it. - ALSO, with a higher flow turbo,.. it will usually dictate LESS boost pressure, not more, so it should be in the ballpark of about 34-35 psi if they do actually have slightly better flow. - You are likely to see some efficiency AND slight hp gains if you get them set to this range instead of over-boosting them like you are.