Hey guys. It's been a real long time since I've been on here. After a bout with health issues I'm finally back at it. I bought a 74 duster that I will be converting into a demon. The demon took a hard hit in the back left and is pretty well junk. So now heres the build. ... I bought a 69 440. Has new .30 over speed pro pistons all machine work done. Balanced ly rods. All new bearings. Set of 915 heads. And I believe the cam is a 557? It's huge. It has double valve Springs. M1 intake and a 850 demon carb. Now here is the issue. Cast crank. I have never built an engine with one. How do I balance this thing If the rodshave been completely balanced with the pistons? Do I use the factory cast damper? I have a forged crank that needs to be turned. But I have ran out of money and am looking to get this thing going. Should I wait to get the crank done or is this cast crank ok for a year or so.? What does this combo make for hp? Is there any thing I need to do to be aware of. What balancer do I use then? Any advice you guys have would be great! Thank you on advance guys. I will post some pics!
440 duster. Need engine build advice
- Thread starter billyboyd
- Start date
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joesnow
Well-Known Member
Wait and turn the forged crank. Otherwise it will always be in the back of your mind haunting you....
moparlover
Well-Known Member
cast crank requires 1. a different harmonic balancer up front (it has an offset or holes drilled to counter the crank balancing if you look at it closely) and 2. a weight-offset torque converter OR flexplate in the back (tq with weights or bm flexplate with a cutout. not both. most normally use the B&M offset flexplate and a neutral balanced Torque Converter, since it makes purchasing easier, so you can buy a torque converter anywhere. The stock method had a neutral balanced flex plate but the torque converter had weights welded on)
forged crank requires 1. neutral balanced harmonic balancer up front, 2. neutral balanced torque converter and 3. neutral balanced flex plate. All 3.
you cannot mix and match ANY of the weight offset parts if you have a forged crank.
everything is neutral balanced.
now the big shocker. Pistons, Rods and Crank need to be balanced together. In addition, if it's external balanced cast crank the machine shop needs the harmonic balancer and flexplate/or torque converter) in order to do it right.
just weight matching the pistons and rods is not a complete engine balance. those are the first two steps.
here's an article about crankshaft balancing
http://www.carcraft.com/howto/ccrp_0803_engine_balancing/viewall.html
forged crank requires 1. neutral balanced harmonic balancer up front, 2. neutral balanced torque converter and 3. neutral balanced flex plate. All 3.
you cannot mix and match ANY of the weight offset parts if you have a forged crank.
everything is neutral balanced.
now the big shocker. Pistons, Rods and Crank need to be balanced together. In addition, if it's external balanced cast crank the machine shop needs the harmonic balancer and flexplate/or torque converter) in order to do it right.
just weight matching the pistons and rods is not a complete engine balance. those are the first two steps.
here's an article about crankshaft balancing
http://www.carcraft.com/howto/ccrp_0803_engine_balancing/viewall.html
roccodart440
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I know the BBC guys run 454 cast cranks to 500hp all day with no issues at all (even the stock car guys) So I'm assuming you could safely do something similar with a 440RB.
I would look into having the cast crank and recip assembly internally balenced. I've hear of it being done. however you may have as much Money in it as a forged unit will cost you.
If you want to extrernally balence it Moparlover is spot on.
I would look into having the cast crank and recip assembly internally balenced. I've hear of it being done. however you may have as much Money in it as a forged unit will cost you.
If you want to extrernally balence it Moparlover is spot on.
moper
Well-Known Member
I dont think the cast crank would be an issue - but - the Speedpro pistons are an old, heavy design. If you run the cast crank with it's lighter counterweights and the heavy rods and pistons, you'll spend more $$ to balance it. Are the pistons mounted on the rods? Are they pressed pin (would be a factory type install rather than bushing the rods and/or just floating the pin)? If they are mounted they have to be dismounted in order to properly balance the assembly. That's risky - it's easy to damage pistons dismounting them. If they are assembled - did you get a balance card with them? I need more details on what you have before I would recommend either crank.
Take the crankshaft of your choice w/damper, and all the rotating assembly, rods, pistons, bearings, rings, torque converter w/ flexplate to your machinist and have them balance the assembly.
Or do what others have done. Bolt all the pieces on, hope it doesn't vibrate......it will. Change more pieces....it still vibrates.
Now take it back apart and have it balanced.......or sell it to some unexpecting other party.
Or do what others have done. Bolt all the pieces on, hope it doesn't vibrate......it will. Change more pieces....it still vibrates.
Now take it back apart and have it balanced.......or sell it to some unexpecting other party.
Jo Diesel
My other car is a Dodge
Go do some scrappin and get your forged crank turned. Last one I had turned was $125 Probably get it turned and balance everything for less than $400. Thats like 1.5 Ton of Scrap
rbdart
Well-Known Member
1st thing I would do is a little research on what you have,does the balancer that was with it as well as the flexplate/convertor have weights or other,may have already been balanced if weighted items are neutral...cast cranks are good upwards of 600hp,and if its already been balanced it will appear to be a forged crank with neutal balance,pull pan and chk numbers on crank then you will know,or visit with the fella you got it from and find out whats what if thats possible,if still in doubt then load it all up and have it chkd out or put a forged unit in,even then I would have it balanced,for me a balanced engine is a happy engine and you will get more out of it and less probs....If its a 69 440 it will be a forged crank...
bOb shingler
Well-Known Member
turn the motor upside down on the engine stand. pull the pan off and have a look see. a cast crank has sharp edges on the counter weights. also it will have 440 cast on it on the first counter weight. if the rods and piston were balance they in all probability were balance to the stock rod and piston weight. check the bottoms of the pistons to see if any holes or milling was done when the pan is off. if every thing looks good go to "440 source" and purchase a cast crank balancer and a cast crank flex plate.
The cast crank has been balanced internally I guess. It had been cut in the weights. I got the whole assembly for 800 bucks, so I'm not really out anything. It seems like it wad a budget build deal. The kids dad passed away and he was selling all the "car junk". I called Jim kilpatrick. He has some deal son cranks he had laying around ready to drop in.I will be taking everything to him for balancing. If the pistons are an issue then Diamond or Ross will be in order. I have the money to finish the build but I don't like cutting into my savings. So I will have a forged crank hopefully in 2 weeks time. Now I do have a set of 6 pack Ross and a set of ly just laying here. Should i maybe employ some of those options as well? This is seriously my first budget build. Otherwise it had been 440 source Stroker kits and indy heads. But those days are now long gone lol. I'm 25 and married....... However my wife is looking for a 67 to 69 barracuda for herself. Which she will build. But that's another subject. So now where do I go from here? Keep the bloc,k heads, and other bolt ons and just start over with crank, pistons, and rods? Thanks for the replies fellas
Btw the pistons have been drilled and balanced. The rods are clean up no burrs. And the crank had also been drilled and also cleaned up. I will post more pics when I get home. It's a night shift thing so around 5am I will have them on here. Thanks again. -Billy
desmo900
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Should you the same with the clutch and flywheel if your running a 4-speed?
JoeDust451
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Try 600 hp easy on cast crank BBCs, You can safely run a cast crank in a BBM at 500+ hp all day long, Don't be afraid of cast cranks, If the assembly is all balanced with lighter pistons it'll last forever.
moparlover
Well-Known Member
nice man you are doing the right thing. it will be an engine you can depend on and enjoy for a long time... also if you ever sell it let me know lol. it will be worth more than 800 bucks if it's done right. it sounds like with the pistons and rods you have you will be fine.
p.s. make sure it's a new oil pump. that's your $40 insurance.
p.s. make sure it's a new oil pump. that's your $40 insurance.
rbdart
Well-Known Member
I would run what you have in a heartbeat,going by what you've stated sounds like its already been balanced,aint nothing wrong with a cast crank or the speedpro pistons,with good headwork you should easily achieve around 525-550 hp,are the pistons flattop[I assume they are with closed chamber heads]I would be chking the compression ratio and try to keep it 9.5 or under if you plan on running on the street and pump gas.....
rbdart
Well-Known Member
May have to re-size them...
roccodart440
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I suppose my machinest is conservative but good info to know
rbdart
Well-Known Member
Looks like cast crank and pistons,got any pics of top of piston,numbers?
Ok. I believe I'm going a new route with this thing. New crank and pistons. Here's what I want. ....600 horse, light weight pistons, ly rods. Should i get floating wrist pins with Ross pistons or pressed? What is the best way to go about this? I want to keep the iron heads and now I'm tearing the block down and cleaning the burs off. I have a 557 purple solid lifter. I also have a set of 6 pack rods. Do I implement those? I guess the ly are good for 600 ponies. But will the heads handle that? I cleaned up these heads and I think they will flow decent. The m1 is getting modified as well. The demon 850 is a vacuum secondary carb. Do I change it to a double pump or replace the carb? If anyone in Wisconsin wants to loan me a hand feel free. I always have cold beer. Please FABO veterans help me create a street bruiser! Thank you guys. -Billy.
rbdart
Well-Known Member
You already have a street bruiser,aint a damn thing wrong with what you have,and the VS carb will be better for the street and you wont be so apt to blasting the tires off it....I'd sell the 6pak rods and keep the LY's....
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