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  #1  
Old 08-30-2010, 06:06 PM
txc360 txc360 is offline
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Default 400/451

hey im new here just joined. doing a 400/451 build, don't know alot about this stuff, but that is why im going to school at the moment. i already have a 74 power wagon with a 400. has a cam .270 intake .280 ex. have a torker intake, which i havn't put on yet. i already picked up a 440 crank(not yet machined) my main question is if i go with 440 rods can i still use stock 400 pistons and can i then go without machining down the counter weight? i love the idea of the 451, figure i can do it cheap if i look long enough for the parts. the crank i found unused for $85 because the guy just wanted rid of it and had it listed for 2 months without a single call. on a college budget at the moment, attending WyoTech in Laramie Wyoming thanks Dustin
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  #2  
Old 08-31-2010, 01:04 AM
DartGT66 DartGT66 is offline
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No, you can't go with factory pistons with 440 crank and rods in a 400 block. The required compression height is about 1.35". Still I like the long rods way better, have done them both ways. KB280 pistons are affordable pistons for such a combo, and they have a quench pad for open chamber heads. Is the crank you got a steel crank or a cast one? Here is some worthwhile reading about the "451". http://www.arengineering.com/articles/451.html
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  #3  
Old 08-31-2010, 01:00 PM
txc360 txc360 is offline
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cast crank, anywhere you recommend to get the kb280s? i had come across that page in researching this stuff. don't quit understand everything, but i think i get the jist of it.
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  #4  
Old 08-31-2010, 02:57 PM
rampage_82 rampage_82 is offline
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You can get the pistons from any speed shop even if they have to be ordered... Summit racing is usually the easiest place to find what you're looking for..
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  #5  
Old 08-31-2010, 03:14 PM
txc360 txc360 is offline
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for cost, don't have much for money sitting round. summit has em for round $400. can you get any better
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  #6  
Old 08-31-2010, 03:21 PM
rampage_82 rampage_82 is offline
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Well you could use the stock 400 rods and go with these.... http://www.summitracing.com/parts/UE...n/?prefilter=1
They are $125 cheaper....
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  #7  
Old 08-31-2010, 04:14 PM
txc360 txc360 is offline
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how much power should i expect off any of the choices? looking for bang for buck. 440 rods aren't bad. $140 for a set off ebay, re-manufactured. so i figured not much more if im buying pistons anyways
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  #8  
Old 08-31-2010, 04:25 PM
rampage_82 rampage_82 is offline
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Heck here's what I'd do... If you're wanting to do it as cheap as possible. I would go with the KB251 pistons, get the 440 crank cut down, then resize your 400 rods with ARPbolts... Go ahead and spend some extra coin and get it balanced (external fine). However for your power potential then that will come down to the head choice. If you throw a set of stock 452's on it with a poor combination of parts then you aren't gonna be making a lot of power. However with some headword or aftermarket heads then you can really start putting down some impressive numbers. However with the cast crank, hyper pistons, and stock short rods I would try to limit the combo to around 500hp. The best bang for the buck heads are the Stealth heads from 440source..
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  #9  
Old 08-31-2010, 04:28 PM
rampage_82 rampage_82 is offline
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Also the long rod vs short rod power differences aren't that drastic, whoever with the longer rods and lighter pistons the engine will rev quicker... It doesn't have to do with rod length, rather solely the piston weight....
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  #10  
Old 08-31-2010, 04:39 PM
txc360 txc360 is offline
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ok thats good to hear, weight can make a huge difference i know. like im working on a 86 conquest, dropping a 318 magnum into. everyone i talked to said i would gain so much weight with that V8. actually im only gaining 75 pounds overall. so sitting at 2875 with about 300hp. yeah your talking internals but same concept. like u said it will rev higher. didn't really put two and two together and think that longer rods won't gain any compression.
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  #11  
Old 08-31-2010, 04:42 PM
txc360 txc360 is offline
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oh and would it be worth it if the motor was a magnum? it had a magnum air filter on it when i bought it, but the previous owner didn't know. gotta run the numbers yet. they had a bunch of stuff messed up when i bought it. needs some rebuilding and retuning. for example, the plugs were barely over hand tight. good thing i ran through a bunch of stuff before i ran it much
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  #12  
Old 08-31-2010, 04:56 PM
txc360 txc360 is offline
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sorry missed ur first of the double post. for heads i going to see if i can get my heads on the flow bench. can get it done really cheap or free here. couple mopar guys i can see what i can find for heads and parts. and yeah not going to go to far with this. my charger just has a 360 in it right now. thinking after the truck is done im going to get another 400 block and do one a bit more hard core for that. don't need more then 500 ponys for my daily driver. plus i might have to drive this from wyoming to minnesota at some point. that could be hard on the wallet lol
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  #13  
Old 09-01-2010, 08:19 AM
DartGT66 DartGT66 is offline
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500 hp "gas station horsepower" is achievable form the factory heads with pretty basic work. With a heavy car and the factory heads, you are not going to see a lot of rpm, so the 400 rods with the heavier pistons should do just fine. The crank balancing is a must, and since you are on budget external is the way to go with this combo. With the 440 rods and light pistons it's very close to balance internally even with the cast crank. What the stroking really does is lower the rpm range, and therefore add torque. If hte rest of the "power parts" remain the same as with a non stroker, you don't see much, if any, power gain. This is especially true with such a small port headed engine as a BB mopar. No matter how you are going to do the stroking, it will not be a bargain unless you get the machine work required free. Machining the mains down, clearancing the block for the counterweights, using prepped 400 rods with decent bolts and modifying hte stock 400 pistons is propably the cheapest way to do it, but the cheapest way sometimes isn't the least expensive or the most sensible in the end to do things.
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  #14  
Old 09-01-2010, 10:02 AM
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JVMopar JVMopar is offline
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I agree with the cost of pistons, rings, bearings, rods, machine work, balancing, etc. It may be easier and cheaper to just go with a kit like this one from Muscle Motors http://www.musclemotorsracing.com/st...t-article.html

I know the 440 Source also has kits but they don't list the prices.

A kit plus $500 in block work a gasket kit, cam, timing chain, etc. You could have a short block for $3000 that's not too bad.
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  #15  
Old 09-01-2010, 10:39 AM
txc360 txc360 is offline
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well the truck already has a small cam which i can leave for now, and beef up later, timing chain, timing gears, extra gaskets, torker intake, obvious motor. got the crank for $85, machining it should be round $100-$150, pistons bout $300, then for bearings and bushings shouldn't be anymore then $100. bought the truck for $1750, only had 58xxx on it. everything i didn't price was either already in the motor or came with it. at that im not even getting close to $3000. including the price of buying the truck. just throwing numbers out there. all ruff guesstimates to me.
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  #16  
Old 09-01-2010, 01:01 PM
txc360 txc360 is offline
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Quote:
Originally Posted by DartGT66 View Post
500 hp "gas station horsepower" is achievable form the factory heads with pretty basic work. With a heavy car and the factory heads, you are not going to see a lot of rpm, so the 400 rods with the heavier pistons should do just fine. The crank balancing is a must, and since you are on budget external is the way to go with this combo. With the 440 rods and light pistons it's very close to balance internally even with the cast crank. What the stroking really does is lower the rpm range, and therefore add torque. If hte rest of the "power parts" remain the same as with a non stroker, you don't see much, if any, power gain. This is especially true with such a small port headed engine as a BB mopar. No matter how you are going to do the stroking, it will not be a bargain unless you get the machine work required free. Machining the mains down, clearancing the block for the counterweights, using prepped 400 rods with decent bolts and modifying hte stock 400 pistons is propably the cheapest way to do it, but the cheapest way sometimes isn't the least expensive or the most sensible in the end to do things.
so basically your saying im better off going with just the crank, heads, and some decent bolt on's. and put that money in something that will move like my charger, right?
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  #17  
Old 09-02-2010, 01:02 AM
DartGT66 DartGT66 is offline
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I just got a small block stroker kit from muscle motors, making a 340 to a 416. Cost was 1199$, and the parts seem to be prepped ok, not just gathered from the shelf.

There is several ways of doing these things. You can do everything for very cheap and hope it will stay together and even produce some power. Or you can do it well using good parts, it will cost a little more, but you can also rely more on it. Or, you can spend even more and get parts that you really don't even need now, or in the future. If you plan for future upgrades, it's a good decision to build the short block so, that it can take them. There is a lot of things that affect the route you choose to follow, and there really isn't any other people able to tell which route is the right one for you, than yourself. Of course, with an unlimited budget it would be a lot easier.... but basically there isn't much power in forged cranks, aftermarket rods, forged pistons etc. What is needed is a good ring seal, without that you will not make power. It means round and straight bores. Other important things is, that you have a good "package", cam, compression ratio, intake and exhaust must work together. If that goes well, then you will be making very repsectable power with very basic hardware. And of course the final performance and the cam etc. choices depends of the car weight and drivetrain, for best performance they have to match too. Otherwise I would have suggested just building a 400, but with a heavy car, propably a low stall converter and realtively long gear ratio you will gain real world performance with more stroke.
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  #18  
Old 09-02-2010, 11:44 AM
txc360 txc360 is offline
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yeah that is what i have been thinking of. do the crank in this one, get some decent power. but thinking im better off building one these 400s all the way for my charger. weighs alot less (3600) and would just make more sense. so if i leave everything as is but just put the crank in, put intake on, and add some headers, what would i be looking at for power?
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  #19  
Old 09-02-2010, 07:56 PM
Cudadrag Cudadrag is offline
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I feel your budget concerns. Its easy to start spending. I'm re-building my 451. Because I have upgraded the heads from iron 452 open chamber 79cc to aluminum B1s closed chamber 65cc everything has changed. I'm replacing everthing. (pistons, rods, cam) Suddenly I'm in for $1500 when I started to just freshen. Only the crank is the same (forged) which I had checked and re-balanced.

If I have 1 recommendation it is to plan your build for a power level in conjuntion of what heads you plan to use. The heads dictate the most on power potential and how tough a bottom you will need. Stock LY 440 rods are fine if you plan to use iron open chamber type head yielding about 9.8-10:1 compression with flat top pistons. about 500 horse potenial. I use(d) Ross 99494 piston. They are $595 at Summit. The Ross piston is 510 gram average. (4.375") They are more expensive than lets say KB but they are forged, lighter and as well tested. If you plan on a higher flowing tighter cc head (eddys, indy what ever) then you need to look at a rod upgrade. Like that of my B1 heads.

A 500 horse target can be had with iron 452 (or other 900 series open chamber Chrysler head. Some porting.) With stock rods and cast (machined) crank with in a low budget. Pistons will be the highest single cost.

I am rooting for you on your goal, and not to fall down the spending hole I did. But my power goals were 650 horse. That damn 150 horse changed everthing (again dictated by the wish to use upgraded heads.) However my motor can easily handle another 150-200 horse lets say from a nitrous shot if I was inclined. As Dart mentioned A tougher build does give more expandable options. Post what you decide.
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  #20  
Old 09-02-2010, 08:44 PM
txc360 txc360 is offline
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well nice to see someone from nearby (where i used to live) grew up in madelia, just south of kato bout a half hour. now im to the point where im kinda looking to what you guys recommend for internals, is it really worth to chuck a bunch in or just do the crank and some good rings. then look for heads from there, or just bench the ones on it. havn't looked to far with heads, even thou its a huge part of the whole deal. i got 3 junk yards in town here, i know two of them have big blocks in them. kinda leaning the 452 direction right now. id like mid 400s hp, preferably little more in torque
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  #21  
Old 09-06-2010, 09:56 PM
Cudadrag Cudadrag is offline
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The 452s did well for me. I still have them and plan to use on a street motor. Mine were ported about as far as they could go. The valves are 2.18 intake 1.81 exhaust. I never had them bench tested for flow numbers. Maybe this winter. The only problem I have ran across is its easy to crack or punch a hole (like tightening the valve covers too much.) That was the reason for the new heads. Got tired of welding up small leaks. Mine have crane rockers (Stock weight) They handled a .590 lift solid cam to high 10 second 3000 lb pump gas car.
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