I was reading on another forum about a mod motor that Ford and Roush made in 94. It was a 4 valve, 4.6 that was bored and destroked to still make 281 ci. Anybody know any thing about this?
640 hp N/A Motor
- Thread starter Marcello96
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news to me that's crazy talk for a 281 n/a mod motor no matter how many valves the thing has.
i know thats why i wanna find out if its true
do you have a link to the other post ?
its the third post from the bottom on the 3rd page
I think that guy is getting things confused. The earliest DOHC 5.4 was back in 98' when Ford designed an all motor 5.4 that made 600hp@7200 for the rough rider off road team. The Cobra R heads were a decendant of that head design. It was also a dual injector. There was a site for it but its no longer available. Something like enduroracing.com
-Mark
-Mark
maybe he meant a 5.4 ??? but I assume the 8,000 rpm's had something to do with that ? I bet building a motor that radical would be way more expensive than a built and blown motor making the same / more power and have better driveability.
I dont know about impossible but rather impractical considering the amount of $$$ it would take to get there. If you had a Ford GT motor and destroked it to get it to rev to 9k rpms with PP heads really aggressive cams, a state of the art intake manifold, a shit load of compression and running stricktly on jet fuel I think it could be done.
I doubt it. You don't have much room to increase the bore on the 4.6 block. This is why the 5.4 uses a larger stroke and the same bore: there is no room for much increase.
If they went with a different bore spacing they would have needed a different length crankshaft and cams. Possible, but then it is not the same engine.
Either way, at 4.6 liters of displacement they would have to rev it to the moon to make 640hp NA, especially with a shorter stroke. 10,000 - 12,000rpm.
So it is either not true, or this was a different program entirely.
Jim Snover
If they went with a different bore spacing they would have needed a different length crankshaft and cams. Possible, but then it is not the same engine.
Either way, at 4.6 liters of displacement they would have to rev it to the moon to make 640hp NA, especially with a shorter stroke. 10,000 - 12,000rpm.
So it is either not true, or this was a different program entirely.
Jim Snover
Mathematically it is not impossible, but it would not be a practical engine. It would not be long-lived, either. And it would be expensive as hell.
Jim Snover
Jim Snover
Jet fuel is very similar to kerosene and diesel.
Modular Performance made over 500rwhp with a BB a few years ago. Add 15% to that and you have 575fwhp. Getting anothet 65hp from 281 cubic inches would be damn hard.
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Think about what formula 1 engines make. Their 2.4L 90 degree V8's and they make 750 hp. It's not impossibe just really, really expensive. I think it could have been done I'm ton a look into it more.
I'd say thats definitely doable. These are technologically advanced and very efficient engines. I've seen 2HP/cid big block Chevies and SBC's, neither being the benchmark ov efficient (base) engine design. I've seen big block Mopars approaching the 2HP/cube mark, well past 1.5 anyways, and while i think they are a better design in general, the aftermarket is a joke compared to the Chevy.
I cant begin to remember where i saw it, but i read about a Mercedes/Penske designed aluminum V8, TWO valves and pushrods... about 200ish cid that made 900HP. NINE-hundred. Thats NA.
Now i pretty much have to call bullshit on that one... but the pictures ov it showed one seriously marvelous looking lil' V8, with some absolutely ridiculous headers flowin' from the ports. The damn collectors were as big as the heads. Even if it 'only' made 700HP, thats still 3.5HP/cid... Wish i'd bookmarked that website...
2.25HP/cid out ov a big-dollar DOHC mod (likely a modified/destroked 5.4 for more bottom end options...?) doesn't seem terribly outlandish...
Al Pappito (???) got 600RWHP out ov his 330, unless ov course he made it a little bigger... hell, even if he did, thats still around 2HP/cid.
I love these engines.
I cant begin to remember where i saw it, but i read about a Mercedes/Penske designed aluminum V8, TWO valves and pushrods... about 200ish cid that made 900HP. NINE-hundred. Thats NA.
Now i pretty much have to call bullshit on that one... but the pictures ov it showed one seriously marvelous looking lil' V8, with some absolutely ridiculous headers flowin' from the ports. The damn collectors were as big as the heads. Even if it 'only' made 700HP, thats still 3.5HP/cid... Wish i'd bookmarked that website...
2.25HP/cid out ov a big-dollar DOHC mod (likely a modified/destroked 5.4 for more bottom end options...?) doesn't seem terribly outlandish...
Al Pappito (???) got 600RWHP out ov his 330, unless ov course he made it a little bigger... hell, even if he did, thats still around 2HP/cid.
I love these engines.
Exactly my thoughts.
Purpose built for an off-road racing car, where it just needs to survive 1-2 races before being torn down and inspected. Any discussion about the potential for building a street motor like this is just insane.
Seriously now, F1 engines are essentially hand made or crafted in extremely small batches and under fairly tight security. They also spin at rpm's up to 19,000.
Get back down to earth guys. Making good streetable power with a 4.6, stroker, 5.0 BB, 5.4, etc is basically a formula now. Plug in your heads/intake, cams, compression ratio, power adder (if any) and you get a rough resulting HP number. Period.
Dreaming of engines made from 'unobtainium' is all fine, but having an ongoing thread about it is a little silly.
+1.
'Jet Fuel' is such a misnomer for a liquid that makes alot of power. Further, it cant be run in a gasoline engine at all.
'Cessna Fuel' would probably be a better descriptor. Or screw the airplane comparisons and go straight to the VP120. There is something special about the smell of VP120 burning on a Saturday morning at the track.
Your use of 'ov' really hurts my brain.
if anything, the biggest thing that confuses me about that story, is that he says "ford modified a DOHC 4.6". granted they were using them in other cars since i believe 91, dont you think they would have waited to do anything like this on a mustang until AFTER they released the 4.6 specifically for the mustang?
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