by BDA
Hi all , great board you have here .
I am interested to know the facts about EMD's performance upgrades along the way from SD40-2 through to the SD70ACe .
Feel free to correct me or fill in the gaps .
I gather the SD40-2 had the 16 645 turbo engine and AR10 alternator to power 6 D77 traction motors . I did read that EMD built 4 super series demo locomotives but not sure which alternator and traction motors - AR16 and D77B SS ?
With the SD50 series came the souped up 16 645F3B with higher max revs and a larger turbocharger for around 36-3800 unreliable Hp ?
No idea what alternator and traction motors - D87BTR ?
SD60 introduced the 16 710 G3 to replace the overworked 645F3B ?
Motors , alternator ?
EMD used AC drive first with the SD60MAC ?
I think I read that the SD70's used a larger alternator to cope with the higher output 43-4500 Hp 16 710 . Was the alternator an AR20 ?
Just at this point what power train differences exist between an SD70 and SD75 ?
Obviously the 70MAC was the AC drive version but I've no idea what upgrades the ACe gets over the MAC though I suspect more advanced computer and cooling systems . The ACe was for T2 emissions and both EMD and General Dislexic seem to have gone with fan forced air to air intercoolers - I think .
In some ways I hope EMD goes with a 12 265 in the future because its hard to argue with less moving parts and a shorter lighter prime mover .
If they can coax 45-4700 Hp reliably out of it I think this may be the sweet spot .
Always did like EMD's , unlike those others they have same day throttle response .
I am interested to know the facts about EMD's performance upgrades along the way from SD40-2 through to the SD70ACe .
Feel free to correct me or fill in the gaps .
I gather the SD40-2 had the 16 645 turbo engine and AR10 alternator to power 6 D77 traction motors . I did read that EMD built 4 super series demo locomotives but not sure which alternator and traction motors - AR16 and D77B SS ?
With the SD50 series came the souped up 16 645F3B with higher max revs and a larger turbocharger for around 36-3800 unreliable Hp ?
No idea what alternator and traction motors - D87BTR ?
SD60 introduced the 16 710 G3 to replace the overworked 645F3B ?
Motors , alternator ?
EMD used AC drive first with the SD60MAC ?
I think I read that the SD70's used a larger alternator to cope with the higher output 43-4500 Hp 16 710 . Was the alternator an AR20 ?
Just at this point what power train differences exist between an SD70 and SD75 ?
Obviously the 70MAC was the AC drive version but I've no idea what upgrades the ACe gets over the MAC though I suspect more advanced computer and cooling systems . The ACe was for T2 emissions and both EMD and General Dislexic seem to have gone with fan forced air to air intercoolers - I think .
In some ways I hope EMD goes with a 12 265 in the future because its hard to argue with less moving parts and a shorter lighter prime mover .
If they can coax 45-4700 Hp reliably out of it I think this may be the sweet spot .
Always did like EMD's , unlike those others they have same day throttle response .