Turbo Upgrade

[Rawze]

(01-17-2023 )CornHauler Wrote:  I have CM871 CPL2733 that we are overhauling with CPL2919 parts and would like to try to tune it up to get a little more power and maybe better fuel mileage. The question I have is the turbo it has on it is a 4309077RX but the 2919CPL asks for a 4309078RX. I would like to use my old turbo until it is wore out and wondered how important it is to upgrade if we want to push it to 550-600 hp. This truck is a 2010 Prostar that is pulling 145k plus all the time.

first and foremost.. there is no such thing as "more power".. and "better fuel mileage"... you got some kind of pipe dream if you think you can have both. Take your pick.. either you want to go up the hills faster and eat the fuel out of it.. or slow down, use less power.. and save fuel, lowering operating costs. - You cannot have both.. that does not exist.


NEXT... if you go to the bigger turbo (the titanium turbine version ) then your fuel mileage is going to go down by about 0.7 - 1.0 mpg just from having to drive that heavier turbine, regardless of anything else you do. - something else to think about.


It sounds to me like you have been a bit mis-informed there..

so ... you need to make a decisions. Either set it up for higher average loads and heavier haul applications and take the fuel hit for the sake of at least some of the engine and turbo longevity.. at the cost of fuel.. or to choose to save fuel, lowering your operating costs and saving more moneys.. but not to be the first one up the hills.


There is an easy way to tell on the CM871's and CM870' what turbo you have without taking them apart. It can be done by checking the cold side impeller retaining nut. The more fuel efficient version of the 500VG has the 12-point nut holding the turbine in place and a slightly smaller diameter shaft.. and the titanium version that is less fuel efficient, but made for higher heat flow/heavy haul, has a 6-point nut and a slightly larger dia. shaft.