You hit just about every point. One to add is that the national speed limit was 55 MPH when the 425 came out. Cruise at 60 MPH verses 70 or 75 and the 425's fuel economy will increase quite a bit. The stuff about needing a certain RPM at cruise range verses the lowest RPM that you can drag a car with doesn't agree with my findings. The 425 is plenty happy in top gear on the highway at 1700 RPM.Night Wolf said:The 425 really isn't all that bad, I used to knock it, but not anymore. Really, its an amazing engine that is only over looked because it simply isn't a 500. Why get a 425 when you can have a 500, ya know? but really its the smae thing. At the time they wanted a lighter engine that was better on gas and less emmissions, and it was.
Yeah 180hp from a 7.0L V8 is weak... but come on... 1977-1979 wasn't really the time for mega-power in any car... with a gas crisis on hand they were trying all they could to get the fuel mileage up. But remember, it isn't HP that gets these boats, or any vehicle moving, its torque. The stock 425 has 320ft-lbs of torque at 2,000RPM. That there is pretty healty and what gives these engines a nice wake up call.
But the 425 isn't a dog....really, considering what it has to move, and how it does it, it is decently quick at it.
Different year 425's DO have differences. The engines are exactly the same but fuel system parts and calibration differ. Even timing proceedure changes.bigblockcaddy said:i have a question..i know that the 77,78,and 79 all have the 425 but i have always wondered since i have the 79 the last year they made the 425 is it more advanced or have a little bit more spunk because they had a couple years to look over the engine from the 77 to the 79..so would the 79 engine be a little more advanced cause its a later model engine of that car??
yea my caddy runs great on streets and flatland..but when i go up north kickin it in overdrive i usually stay around 65-70mph but thats about all it will do going up mountains.tripleyellow78cad said:my 78 cd 425 is pretty powerful and fast for an old car , it only needs more power on large steep hills , like the i-5 grapevine hill to la
i live in ca,
Heh... learn something new everyday...The Ape Man said:Different year 425's DO have differences. The engines are exactly the same but fuel system parts and calibration differ. Even timing proceedure changes.
bigblockcaddy said:yea my caddy runs great on streets and flatland..but when i go up north kickin it in overdrive i usually stay around 65-70mph but thats about all it will do going up mountains.