going v8
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From: Alston, MI
going v8
my 300 i6 has a nasty piston slap and a spun main bearing, along with cooked wires for the tps and other electrical issues and the rear main seal puking out oil. 261k miles, it's had a pretty rough life and it's ready to be yanked. my original plan was to yank the 351w/zf5 combo outta a 91 f350 4x4 for it because it's a basic plug and play deal, until my instructor said to drop in a carbed 302 for mileage reasons (which boggles my mind because last time i checked, the 351 and 302 got around the same mileage in a full size truck). so i started looking around to doing a torque build on a 302 (i have for my mustang, but mustang's getting sold at the end of november) and decided that it's not as easy as i thought it was going to be. so i decided that i'd do a port and polish on the heads, higher ratio rockers, higher compression pistons, and leave the 2v carb on it. either motor would get a 3" single or 2 1/4" true duals. after it's all said and done, which do you think would get better mpg? also, which one would be more reliable?
either motor will get the zf5.
either motor will get the zf5.
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From: Pueblo, CO
I had a 302 in an F150 and it was under powered. I've never had one with a 351 but I seriously doubt there would be much difference in mileage, especially if you keep the EFI and put in the 5 speed behind it.
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From: Eastern Ky
Why not just get a master rebuild kit for the 300? Its a LOT cheaper, and frankly....No reason to kill yourself for another 4.9l....Just 2 more cylinders and another head....
Seriously, awesome time to do a 300 build...
Seriously, awesome time to do a 300 build...
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From: Alston, MI
don't get me wrong, i like the 300 i6, but this one's been giving me more trouble than it's worth. and yeah, the rebuild ain't a bad option, but i'm going to have to either track down a new wiring harness for it because it's got more electrical issues than i'd like to deal with and i already have the 302 donor vehicle and 351w donor vehicle so the only swap that would kill the bank is the 302 build because it'd be built for torque.
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From: Pueblo, CO
if you wanted you could do some HP mods to the I6. and as good as the C6 tranny is if you want better economy ditch it for the 5 speed. the 351 and 300 have the same bolt pattern. either way I don't think you'd be disappointed.
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From: Eastern Ky
don't get me wrong, i like the 300 i6, but this one's been giving me more trouble than it's worth. and yeah, the rebuild ain't a bad option, but i'm going to have to either track down a new wiring harness for it because it's got more electrical issues than i'd like to deal with and i already have the 302 donor vehicle and 351w donor vehicle so the only swap that would kill the bank is the 302 build because it'd be built for torque.
....LOLSeriously man....I had a carbed 351w...And talked myself out of it...$300 JUST to swap and prep the danged thing for the swap...Wasn't worth it...
Considering I had a 250k+ mile engine.....Not worth it...
Another harness, a rebuild kit....and some extra goodies added in, will suit your needs, and be a ton easier...
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From: Alston, MI
....LOLSeriously man....I had a carbed 351w...And talked myself out of it...$300 JUST to swap and prep the danged thing for the swap...Wasn't worth it...
Considering I had a 250k+ mile engine.....Not worth it...
Another harness, a rebuild kit....and some extra goodies added in, will suit your needs, and be a ton easier...
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From: Eastern Ky
the 351w i have for it's efi and it only has 100k on it. the only thing i really need to change on the motor is one of the exhaust manifolds. i have the complete donor vehicle (1991 f350 4x4 crew cab long bed). the 302 is the same deal, i have the complete donor vehicle if needed.
Still....THe 300....Lowly as it is, and slower than molasses on a cold day...
A full rebuild/performance build...It's cheaper, easier, and will be a LOT less maintenance than the v8's.....Just saying...
Plus....You will nab around 15-16mpg city...and about 17-20mpg highway...
Thats what I average...lol
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From: Eastern Ky
Really? WOW....
Last years Ky Meet....I got 16mpg over the course of a 120 mile trip, 1 way...1/3 @ 55mph....2/3 @ 70mph...
On the way back, I drove 60-65 mph in the 70mph zone, and 55mph the rest of the way....17.7mpg....
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From: Alston, MI
yeah if i had your truck i don't think i'd be wanting to yank the motor. my tps is sending incorrect signals still (won't sense WOT) so it runs lean all the time. fueleconomy.gov rated this truck at 13city/13hwy so i'm still doing better than what the site said haha.
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I'd probably keep the 300 and put a 5 speed with it.
I have a 302 and while it has been a darn good motor, low end torque it doesn't have. Even if you build one up a little, the power band may move up. Then it will really need better gears.
I have a 302 and while it has been a darn good motor, low end torque it doesn't have. Even if you build one up a little, the power band may move up. Then it will really need better gears.