not sure if this is where i ask this question but here we go. guys i was wondering what is all envlved in building a 451 from a 400 besides the grinding of the 440 cranks mains. is there block or cylinder notching involved? pics an all the technical specs would be greatly apreciated. an what kind of power are these capable of?

Google "451 manifesto". It is well documented in this article.

thanx

Click on the books page and you'll find plenty of information covering stroker motors.

http://www.moparts.org/moparts/books/index.html

The mains need turned down to 400 size and the counterweights need turned down to 7.25 ish diameter. Then you can run a 6.76 rod and a 1.32 ch piston which is a popular piston for many combos. I'm doing a 3.9 offset stroke with a chevy 6.70 rod and 1.32 piston. It seems people are always very happy with the 451 combo.

Some background on the 451 "B". I think much of the success of the 451 combination was from articles in Chrysler Power magazine in the late 1980's.
They were putting turned down 440 cranks in with stock cast pistons milled for the compression height. Because of the shorter deck height the pistons weighed less than a 440 so the engines would RPM good and were cheap to build, considering no one wanted 400 blocks, they were much cheaper than buying a 440. One of the first failures was the piston pin pulling out of the stock cast piston at sustained high rpm. So custom (at the time) forged pistons were used and I think the custom pistons also allowed running the longer 440 rods. At this point 451 "B" had the same stroke and rod length (and about the same bore size as a 0.060" over 440), but with pistons that weighed about 1/2 as much as the 440 piston.
The lighter weight pistons also reduced the stress on the crank and rods. So at the time the big deal was the low cost of the 400 block and light weight pistons. The "B" engine may also have some strength advantages over the 440 "RB" with shorter cylinders they should be stiffer, the shorter deck height uses shorter pushrods (stiffer and weigh less),the smaller main bearing size reduces friction and allows more material in the main webbing and caps, but that's usually not a problem on a 440, but the difference is usually mentioned.
Another issue is the shorter deck height "B" engine at 9.98" compared to a 440 "RB" at 10.725" results in the "B" engine being slightly narrower so it fits easier in A-Body cars.
Anyhow, 500 HP is easy with decent flowing heads and a mild cam. With better heads, and some cam 600 HP is not too hard to make. 700+HP is possible with good aftermarket heads and a bigger roller cam, but at this level you will want a stronger than stock crank and rods, so larger strokers are usually built. The 500" "B" stroker with 4.15" crank still uses the longer 6.768" rods and a pretty short compression height piston requiring oil ring supports. This is a nice combination for a higher winding 7,000+ RPM engine. The 4.25" stroker 512" kits use a shorter rod, and are really nice for a street engine that does not need to spin 7,000 RPM.

I have seen friends Duster go 9.70s with 451, stock eddie rpm
w/452 heads ran 10.2/10-30s stock rods, (aries pistons tho.)
430 gear 33 tall tire,, oo the motor stayed together some 10 years

this is all sounding sweet to me thanks for the info guy's ur awesome....

have one sitting on the stand ready to go in my customers duster 451 11 to 1 comp comp solid cam 565 lift 242 duration out of the box eddys team g intake and 850 quick fuel carb dynoed at 538 hp and568 torque 3100 pounds we figure 10.80 to 10.90 no problem i like low deck strokers because they make good torque down low in the rpm range this motor made 500 torque at 4000 rpm!

awesome seems a no brainer they seem to be rather cheap to build an make awesome power seems like a win win

I built mine for just over 5 grand. Mine's a .040 over block for 452", in a 3780 lb. street B-Body, and it has gone 12.0's in street trim with plenty more to find. Take a ride in it here: https://board.moparts.org/ubbthreads/show...e=1#Post6920806

Watch the tach when I hit the throttle a few times. RPM's on demand, baby!

sweet sattelite i had a belvedere wagon 67 loved her till some ass rear ended her....

I like mine alot, I built it at home, and it does pretty much what I wanted it to do.

PM me if you have any kind of specific questions you don't want to post, but it's all be covered pretty well.

The way I look at it is:
If you like 440s, then you will love the 451 low deck.

It acts similar to a bored out 440 in some ways, but seems to like RPM maybe slightly little more...it is smaller on the outside...gives more room for big headers, and more room for taller intake manifolds.

No better use for an old steel 440 crank with trashed mains

All the work is in the crankshaft.

Mine makes 525hp 500tq at the rear wheels and is street driven on a regular basis.

I believe it all clears the block but I'm not there yet with my build.

that would be great talking after the couter balance been cut down

Here is one I recently did....you'll notice the chamfer on the inner crank throws. This must be done to clear some block casting in those areas. You can also gring the block to help clearance this. It is also possible to put a 440 crank in with no or minimal crank work, but a lot of grinding in the upper saddle areas. A poor mans stroker is possible this way, but its not the best way in my opinion. I did one with a cast 440 crank to see what it involved, and didnt care for it much myself.