Paccar MX-13 tuning

[Texasdude74]

The 485, 500 or 510 is the way to go in my opinion. 16.5:1 compression vs 17.5:1 for the lower ratings. I think the lower compression of these things is the reason they're not having head gasket, cracked head, liner, counter bore and fretting issues like Cummins. The X15 is going to have even higher compression and IVA's. They've built their own coffin.

In turbo diesels larger displacement is all about being able to spool up a larger turbo, the displacement itself doesn't make any more power. Modern injection systems and VGT or compound turbos mean a smaller engine can still move large amounts of air at a reasonable rpm. Some of these 13 liters will blow the doors off the old 3406 a,b,c etc of yesteryear. And those were the hot rods of their day, marketed to owner ops. These little things are mega fleet engines.

The MX13 and D13 seem to be the best of the breed and are eating Cummins market share like Rosie O'Donnell at a buffet. The worst seems to be the DD13. You can't get a DD15 in a Western Star car carrier, the drop axle is too low and that engine won't fit. Only the ISX with its short deck height, but a guaranteed failure and the DD13. No one wants the ISX so everyone ordered DD13's and they're complete junk. Incapable of passing a shop or getting up a hill. It's so bad that '17 will likely be the last year of the Western Star car hauler if they don't offer a different engine. They need to figure out how to shoe horn a DD15 in there.