Re: 400 vs 451 vs 470
[Re: Streetwize]
#70640
06/10/08 12:17 AM
06/10/08 12:17 AM
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Anonymous
Unregistered
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Anonymous
Unregistered
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yup.. a 470 is a KILLER engine that can make some seriously SICK horsepower.
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Re: 400 vs 451 vs 470
[Re: chrisf]
#70641
06/10/08 01:28 AM
06/10/08 01:28 AM
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Joined: May 2008
Posts: 5,399 Aurora, Colorado
451Mopar
master
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master
Joined: May 2008
Posts: 5,399
Aurora, Colorado
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I did the 451cid back in the early '90s and just broke it two years ago. When I built the engine, there were no inexpensive crank and rods, and not many places to get pistons. The crank was a stock 440 crank machined to fit the 400 block, stock reconditioned 440 rods, and custom dished Ross Pistons.
Now days there are alot of stroker kits avaliable at affordable prices. The 451 has a good rod ratio (same rod length and stroke as a 440, with a larger bore and shorter/lighter pistons) and a decent compression height piston. The 470 uses shorter chevy rods, but the compression height is slightly more. The 470 would be good for a truck engine. It should make lots of torque. The 500 stroker kit with 440 length rods uses a really short piston. Good for racing, but for the street the short piston may reduce the life of the rings?
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Re: 400 vs 451 vs 470
[Re: Mr.Yuck]
#70646
06/11/08 04:08 PM
06/11/08 04:08 PM
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Joined: Aug 2005
Posts: 989 WI, USA
67dodge67
mopar addict
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mopar addict
Joined: Aug 2005
Posts: 989
WI, USA
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Quote:
my buddy swears by the 470-472 400. He's been doing them for years.
470 all the way!!
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Re: 400 vs 451 vs 470
[Re: 67dodge67]
#70647
06/11/08 04:34 PM
06/11/08 04:34 PM
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Joined: Jan 2005
Posts: 12,424 Kalispell Mt.
HotRodDave
I Live Here
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I Live Here
Joined: Jan 2005
Posts: 12,424
Kalispell Mt.
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I say go as big as you can afford! Really your mpg is going to be bad worse or worst with those motors if all else stays the same. The way the bigger motor could get better mpg is gear it down more. Calculate out how many rpm at 60 and cut it in 1/2 since you only suck in air every other revolution then multiply it times the displacement, this will tell you how much air your engine will displace per mile. You can change the rpm or the displacement to be equal to any of the other combos of gears and displacements. 1 Example 400 / 2 X 3000 rpm = 600,000 cubic inches per mile 2 Example 500 /2 X 2400 rpm = 600,000 cubic inches per mile If you have a 400 running 3000 @ 60mph and are happy with the mpg build a 500 and gear it to turn 2400 to keep the same efficency. Plus you will get more tq and a little more fun when you rev it to 6000 You are still gonna get about the same miledge with either, and in my experiance the bigger motors turnning slower even displaceing the same amount over time will get better mpg. Velocity in the ports is about the same but the bigger ones just seem to run more eficent. Consider the freight train as a perfect example, pistons bigger than 5 gallon buckets and they run 300 rpm and pull a mile long load of coal and get incredible mpg (or is it gpm ) relative to there size. Or mabey down to earth more think about an excursion weighing 5 times what a geo metro weighs with probably 3 times the frontal area and almost 6 times the displacement gets better miledge than if you drove 5 geo metros the same distance and it is way faster than a geo. In my opinion get the biggest motor you can and gear it up to get the efficency you want. You will reach a point of diminishing returns when you motor spins low enough to get about 10inches vacume at cruise and the bigger engine will do this at a lower rpm than the little motor.
I am not causing global warming, I am just trying to hold off a impending Ice Age!
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Re: 400 vs 451 vs 470
[Re: 70Dustmite440]
#70649
06/12/08 11:55 AM
06/12/08 11:55 AM
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Joined: Feb 2003
Posts: 1,646 Ontario,Canada
firefighter3931
top fuel
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top fuel
Joined: Feb 2003
Posts: 1,646
Ontario,Canada
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Here's a 505 i helped sort out for a buddy.....very basic build that would be perfect for your truck. The same numbers could be made with a 470 i'm sure. The rundown : SD intake, Proform 950, 10:1 compression, stock stealth heads, Engle K60 custom grind 112* lsa, stock non-adjustable rockers, hv oilpump, windage tray, hemi repro pan. Idles smooth and makes gobs of torque. Ron
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Re: 400 vs 451 vs 470
[Re: firefighter3931]
#70652
06/12/08 12:22 PM
06/12/08 12:22 PM
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Joined: Feb 2003
Posts: 4,204 Fort Worth, TX
Clair_Davis
master
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master
Joined: Feb 2003
Posts: 4,204
Fort Worth, TX
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So, 509hp and 592lbft, all under 5K and THROUGH HP MANIFOLDS? That may just be the perfect stealth bullet for my Sport Fury... Clair
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