All eyes are on the new Maxidyne

[RFCDrum]

The 300 series had either the scoop (early models '73-'75) then the 2 stage (later models).You may have seen trucks with both,Rob,but they could possibly already been converted to the 2 stage(leaving the scoop useless). The Canadian trucks used the scoop longer in production,and had a foul weather intake set up like the old oil baths,so it used the upper intake tube to return just under the hood . Hope this makes sense to you.

The 300 series had either the scoop (early models '73-'75) then the 2 stage (later models).You may have seen trucks with both,Rob,but they could possibly already been converted to the 2 stage(leaving the scoop useless). The Canadian trucks used the scoop longer in production,and had a foul weather intake set up like the old oil baths,so it used the upper intake tube to return just under the hood . Hope this makes sense to you. Al

So this was similar to the Canadian Kenworths and Western Stars that the upper tube just goes into the engine compartment to circulate hot air for the extreme cold?

Rob

[2stacksuperdog]

The 300 series had either the scoop (early models '73-'75) then the 2 stage (later models).You may have seen trucks with both,Rob,but they could possibly already been converted to the 2 stage(leaving the scoop useless). The Canadian trucks used the scoop longer in production,and had a foul weather intake set up like the old oil baths,so it used the upper intake tube to return just under the hood . Hope this makes sense to you. Al

So this was similar to the Canadian Kenworths and Western Stars that the upper tube just goes into the engine compartment to circulate hot air for the extreme cold?

Rob

The plow trucks around here have the ability to suck from under the hood and from outside. They want to keep the dry snow out of the air cleaner coming off the plow

[41180]

i see kscarbel didnt reply to you 84superdog. i agree he has a problem. ether he got fired by mack or volvo r something because he has a horrible attitude. we have a new mack and its a great truck and have talked with other guys with newer macks with the mp engine series and they have positive things to say about them.

[bbigrig]

Has anyone looked at the new Super Econodyne package? Most people dont even know it exists, Mack sets up a pinnacle axle back with all the smart way aerodynamics and Michelin X-one tires, then puts in an MP8 445 Super Econodyne engine and M drive 12 spd transmission with a .78 OD, some 2.66 rears, yes 2.66 rears. the Super Econodyne package has its own engine programming to get the power band down low, it makes 445hp from 1500-1800rpm and 1750 tq from 1080-1380. It looks like the new setup will be pretty good for OTR fuel mileage getters, Oh and the new econodyne engines now have Econoboost torque curves. The MP8 505 Econodyne with Econoboost makes 1500 ft lbs under 1000rpm and stays over 1500 all the way to 1700rpm peaking at 1750 ft lbs, holding over 1500 ft lbs. for over 700 rpm, thats a pretty good toque curve for a 13 liter with emissions on it.

Our new Pinnacles are running the MP8445E engine. On some big grades I have been amazed letting that engine lug down to 1100rpm thinking I am going to need to down shift soon only to find I don't need to make a move. These MP8's seem to work harder down around 1200rpm. Coming out of the Mack ASET era I was really surprised by the low end torque and stamina of the MP8. We are shifting alot less on any hilly terrain with these motors. Running 13spd Fullers with Merritor 3.55's seems to work great for us getting high 7's (mpg) with 44,000 payloads. The super Econodyne sounds great, but I and my dog salesman are skeptical about its pulling power and fuel mileage on constant hilly terrain. I would love to test one out someday! Edited March 20, 2013 by bbigrig

[RFCDrum]

The plow trucks around here have the ability to suck from under the hood and from outside. They want to keep the dry snow out of the air cleaner coming off the plow

Cool and I like the idea that Mack had with the foul weather deal. I do remember seeing some trucks with the valve control on top of the dash.

Cheers, Rob

[rsb502]

Our new Pinnacles are running the MP8445E engine. On some big grades I have been amazed letting that engine lug down to 1100rpm thinking I am going to need to down shift soon only to find I don't need to make a move. These MP8's seem to work harder down around 1200rpm. Coming out of the Mack ASET era I was really surprised by the low end torque and stamina of the MP8. We are shifting alot less on any hilly terrain with these motors. Running 13spd Fullers with Merritor 3.55's seems to work great for us getting high 7's (mpg) with 44,000 payloads. The super Econodyne sounds great, but I and my dog salesman are skeptical about its pulling power and fuel mileage on constant hilly terrain. I would love to test one out someday!

I wouldn't mind trying one of the super econodyne trucks out if I were still trucking otr, however I think it can be made better with a couple changes. I would try to order the chassis, cab, engine and rolling hardware but swap the rears for a slightly higher ratio and use a manual 10 spd direct transmission. If economy is the end goal they have a great product but going from an od tranny to direct and swapping ratios to get the same rpm/road speed would benefit efficiency. Od transmissions are great for keeping rpm down but the higher the od ratio the more power it takes to turn it, go with a direct 1:1 top gear and you will pull better on grades and have less parasitic loss thru the drive train in top gear. Makes sense to me and so does the Mack approach of using the automatic. They are trying to build an efficient truck for the steering wheel holders that can't figure out when to shift appropriately themselves so they let a computer handle it for them.