I'm looking at buying a '93 E150 with a 5.8L that has a broken rod. Right now I'm exploring options for a replacement engine. I've heard that the 5.8 gets significantly poorer fuel mileage than the 5.0. Is this true in your experience?
I presently own a '92 E150 with a 5.0, and it's a great truck, but the body is rusting away, and it's impossible to get body parts for this 'orphan' body style. So I'm wondering if swapping the 5.8 for a 5.0 is worthwhile, and what parts beside the engine itself would need to be replaced.(i.e. the ECU? Exhaust/intake parts?, etc)
Below is a list of parts that are different between the 351/302. Someone correct me if I am wrong..
Exhaust Y-pipe (it is wider for the 351 so you may be able to modify it)
Accessory mounting hardware. (anything that bolt to the heads.)
Computer (some say yes some say no)
From what I have read the 351w has allot more torque, but gets about the same gas mileage. Providing you are nice to it. I say get the 351w rebuild... But I can understand that you have a good 302. You have all the parts needed for the swap(providing both have auto trans), so it would not be that hard or expensive.
Thanks for another helpful reply. I'm not sure I want to totally disable my present van, which is why I'm weighing options. I'm leaning towards a remanufactured 5.8, unless I can find a good used one. Any major differences from 93 to the later models? That is, if I have the original 93 with it's peripherals, would a 5.8 from say, 98 present any problems?
In 95 they started changing them to hyd roller cams. Mass air came along in there somewhere too. The last year you will probably find one will be 97 in an HD truck. There should be no problem, as a 69 model longblock would work. The electronics are your main issue.
I am considering an engine swap myself and from what I've heard, the 351 (5.8) engine is better. I have actually driven both and yes, there is a big difference in power but the 302, despite being smaller doesn't get much better mileage. In fact, the 302 is more of a Mustang-like, car engine, unless modified is actually inferior than a 300 I-6 (which I have right now). Just ask Kemicalburns at the 1980-1996 Bronco forum, he did the swap (302 to 351W) and actually improved his mileage. In any case, it is a rather easy swap and the tranny bolts right on...
My dad's 1988 302/AOD/3:55 gets 16mpg on the highway
MY 1992 351/E4OD/3:55 gets 13 to 15 on the highway depending on speed. I got 13.5 mpg at and average of 80 mph on the way home from st louis in march.
The 351W has a taller deck height than the 302. Since the deck height is taller, the stroke is longer. The banks are further apart because of the taller deck height. They are very similar engines. The 302 will have to work harder to move the truck than the 351W will. There is no replacement for displacement.
RPM for RPM, a 351 will burn a little more fuel because it's a bigger engine.
But the extra power means the engine doesn't have to work as hard (less fuel)...
As a good rule of thumb, the 351 will get better mileage on heavy loads/towing, and better mileage on accleration. The 302 will get better mileage just cruising along at a given speed.
There are so many variables it's hard to compair, you can't say my 302 gets 16 mph and my dad's 351 gets 10 so the 351 is worse. There could be things wrong with my dads truck (and there are) causing it to get poor mileage. The only way to tell is when they came off the assembly line and were new.
I dont think the mileage difference between a 302 and 351 should sway your decision to use either engine....the difference is too close to make it a factor.
Thanks for all the replies. I may have found a relatively low mile (120000KM) 5.8l in a wrecked plow truck. It had an oil pan leak (rust), so the yard owner is going to fire it up and measure the oil pressure etc. I'll probably take it to the local rebuilder for a once over before I install it. I'm considering putting a set of headers on it as well, any recommendations?