Moparts

cast crank on to 451 stroker

Posted By: NachoRT74

cast crank on to 451 stroker - 06/30/09 10:21 PM

give me one REASONABLE REASON to not use a cast crank on to 451 stroker engine IF IS A TOTALLY STREET CAR and maybe just an ocasional WOT on a traffic light with some stupid guy challenging.

NOTICE I'M TALKING ABOUT A TOTALLY STREET CAR... I mean that because 80% of members on all boards thinks only on race/strip cars
Posted By: Dave64

Re: cast crank on to 451 stroker - 06/30/09 11:50 PM

Use it. It will work fine.
Posted By: MoparforLife

Re: cast crank on to 451 stroker - 07/01/09 02:00 AM

Mopar cranks are over kill. Not noted for breakage.
Posted By: bobby66

Re: cast crank on to 451 stroker - 07/01/09 02:06 AM

Get the right balancer and flex plate.
Posted By: RapidRobert

Re: cast crank on to 451 stroker - 07/01/09 02:26 AM

If everything is going to be (re)balanced can the std dampener be used rather than the oddball one? Nacho what pistons are you going with
Posted By: MoparforLife

Re: cast crank on to 451 stroker - 07/01/09 02:43 AM

Quote:

If everything is going to be (re)balanced can the std dampener be used rather than the oddball one? Nacho what pistons are you going with


Sure if you have the assembly neutrally balanced. It will take some slugs of mallry metal to do it.
Posted By: NachoRT74

Re: cast crank on to 451 stroker - 07/01/09 04:14 AM

is a VERY future plan, since I'm working now on KB240s piston setup. I want to go step by step, beside the fact I got everything BEFORE get this crank ( FOR FREE BTW )

I would use the same pieces I have now... my actual 400 damper, already counterweights on TC, and rods... well just if I get some 440s dirty cheap will use them, but being will be hard LOCALLY, use my existant 400 rods is actually on plans... yes I know, rod ratio and everything about rods weight, but as stated is STREET and on the other side, pistons will be with longer skirts.

I have been adviced about use just forged crank to make this, but REALLY I'm not thinking on race ( ever ). I get scared at high speeds, but likes to feel the WOT sensation quite often, that's why I KNOW FOR SURE I won't race. I don't consider myself a pilot, and I'm very respectfull with speeds, specially on an American Car.
Posted By: polkat

Re: cast crank on to 451 stroker - 07/01/09 04:31 AM

Did I read this right? You plan to use everything you already have, and are using KB240's? Unless I'm mistaken, KB240's were designed for a standard stroke 400 to increase compression. Even with short rods they would stick up way too far with an RB crank...or am I wrong?
Posted By: Dusted_Ya

Re: cast crank on to 451 stroker - 07/01/09 04:42 AM

not to mention a 400 dampener and a 440 dampener are counterweighted differently.
Posted By: NachoRT74

Re: cast crank on to 451 stroker - 07/01/09 05:21 AM

Quote:

Did I read this right? You plan to use everything you already have, and are using KB240's? Unless I'm mistaken, KB240's were designed for a standard stroke 400 to increase compression. Even with short rods they would stick up way too far with an RB crank...or am I wrong?




nooo way... I'm telling I'm soon to work on KB240s pistons upgrade with my 400 block and crank because I already have everything of that in hands. So my actual project is still running. The 451 stroker is a very future plan and depending on budget for that moment will go with the rest of parts. I just got the 440 cast crank in hands for free but I will keep my plan on the piston upgrade to my actual 400 setup, will have fun with that and then will go for the next step with the stroker.
Posted By: NachoRT74

Re: cast crank on to 451 stroker - 07/01/09 05:24 AM

Quote:

not to mention a 400 dampener and a 440 dampener are counterweighted differently.




really? didn't know that I thought where the same.

what about TC counterweights ? are they different ? or are they simply the same but positioned different ?

diff flywheel/flexplate ?
Posted By: bobby66

Re: cast crank on to 451 stroker - 07/01/09 11:17 AM

If you have to add mallory to balance it you might as well get a steel crank.
Posted By: cornucopia

Re: cast crank on to 451 stroker - 07/01/09 12:32 PM

Quote:

Quote:

not to mention a 400 dampener and a 440 dampener are counterweighted differently.




really? didn't know that I thought where the same.

what about TC counterweights ? are they different ? or are they simply the same but positioned different ?

diff flywheel/flexplate ?


the 400 and 440 cast crank have the same balance factor. you can interchange the weighted converters and flywheels with no problem.
Posted By: NachoRT74

Re: cast crank on to 451 stroker - 07/01/09 01:47 PM

but is true the dampener is diff between 440 and 400 cast cranks ?
Posted By: moper

Re: cast crank on to 451 stroker - 07/01/09 03:35 PM

You can. But, you will spend some cash to have the cast crank counterweights turned down to fit your block in addition to the normal turnign down of the mians, and you wil need to mock up the block because I'd bet they hit the main webbing a little too. Then you have the balancing issues. You need a 440 dampner for the cast crank, plus the torque convertor weight for the 440, plus you'll need mallory anyway because you turned off a couple hundred thou of counterweight metal on the outer edge of it... It sounds like a smart a answer, but just buy the 440Source B wedge 3.75 stroke crank and run that (after it's checked for size and taper). It's a lot less hassle. Then you can run any nuetral (forged crank) balancer and any nuetral convertor, and won't need any mallory.
Posted By: bobby66

Re: cast crank on to 451 stroker - 07/01/09 03:39 PM

Quote:

but is true the dampener is diff between 440 and 400 cast cranks ?




There are pictures of the dampeners in question in the tech archive section. Look pretty different to me.
Posted By: NachoRT74

Re: cast crank on to 451 stroker - 07/01/09 03:50 PM

ok, if so, then is becoming HARDER with a cast crank to make it work.

where would meet to need to turned down the counterweights ? aren't the 400 and 440 block same room inside on area below cilinders ? the oil pan is the same, gaskets and everything. Block is diff being taller, but thats on top, not on bottom of cilinders. Timming chain is teh same so distance between crank and camshaft is the same, so block should it be basically the same above crank level... or not ?

( yes I know about the 440source stuff )

then, you are saying about the TC weight for the 440, but some of the rest of ppl is telling opposite, being the same than my 400 TC ( already MP unit with weights welded )

then also on diagrams to mount TC counterweights, sheet states 383/400 but doesn't say 440.

Ok I still can't believe we CAN'T get an agreement on some that should it be already stablished.
Posted By: NachoRT74

Re: cast crank on to 451 stroker - 07/01/09 03:51 PM

Quote:

Quote:

but is true the dampener is diff between 440 and 400 cast cranks ?




There are pictures of the dampeners in question in the tech archive section. Look pretty different to me.




aren't those pics making comparision between forged and cast crank dampeners ?... I'm talking about being both cast cranks.
Posted By: NachoRT74

Re: cast crank on to 451 stroker - 07/01/09 03:59 PM

then... why I would need to turnd down a cast crank and not a forged crank IF both are same stroke, so same size ?


ok, guys maybe is my ignorance but lot of this stuff sounds simply without logic.
Posted By: marvo451

Re: cast crank on to 451 stroker - 07/01/09 07:24 PM

You would theoretically have to turn the counterweights on any 440 crank to make a low deck 451 as the counterweight diameter is larger than on a 400. Also, a steel crank is heavier than a cast one and because of that will internally balance.
Posted By: AndyF

Re: cast crank on to 451 stroker - 07/01/09 07:58 PM

I was going to do a cast crank 451 build just to sort out these questions for myself but I never got around to it. I'm pretty sure that if you use lightweight rods and pistons you can get it to balance internally without any heavy metal. That allows you to use the good dampers and flexplates. You can also just add weight at one end if you need to, for instance, use a neutral damper and an offset balanced flexplate.

The journals need to be cut and the counterweights need to be cut down to clear the main webs with either a forged or a cast crank. Depending on what kind of shop capability you have in your local area it might be cheaper to buy a new 451 crank than rework an existing 440 crank. It all just depends on the situation and the size of the wallet in question.
Posted By: 71 FJ6 Charger

Re: cast crank on to 451 stroker - 07/01/09 10:00 PM

Posted By: bobby66

Re: cast crank on to 451 stroker - 07/01/09 10:31 PM

Quote:

Quote:

Quote:

but is true the dampener is diff between 440 and 400 cast cranks ?




There are pictures of the dampeners in question in the tech archive section. Look pretty different to me.




aren't those pics making comparision between forged and cast crank dampeners ?... I'm talking about being both cast cranks.




There's another picture of a 440 balancer in there. Looks different from the cast 400 balancers that I have.
Posted By: NachoRT74

Re: cast crank on to 451 stroker - 07/02/09 01:18 AM

Quote:

You would theoretically have to turn the counterweights on any 440 crank to make a low deck 451 as the counterweight diameter is larger than on a 400.




but why ? aren't the block the same size on that area ? if oil pans are same width to both blocks that mean block walls are same width so both cranks fits on same room... OR NOT ?
Posted By: patrick

Re: cast crank on to 451 stroker - 07/02/09 02:00 AM

width is the same, but the bottom of the bores are closer to the crank centerline on a B compared to an RB
Posted By: moper

Re: cast crank on to 451 stroker - 07/02/09 11:31 AM

I've done forged that didnt need the diameter reduced but did need a few spots on the webbing clearanced... But with a cast one, no way. I believe it's about .200" to take off. You've been told they are different and 440source had an entire different crank made for the B wedge... so those two seem to hint that it's the truth. If you feel this can't be so, get both cranks and measure them. B and RB look the same. The are NOT the same, but they look it. In regard to Andy's thoughts... you'll save the money on the crank to spend it on pistons and light rods? I don't see the logic there but as he adds, your situation and wallet may be different than mine.
Posted By: NachoRT74

Re: cast crank on to 451 stroker - 07/02/09 04:03 PM

I know RB and B cranks are diff, but room inside block does look exactly the same so I can't see a reason to reduce diameter on counterweights to fit an RB crank on a B block.

I know maybe could need some angle grinder on counterweights to get some clearence, but Cut the counterweights because diameter ? seems no logic.

Then we can talk about experiences checking here ( yes I asked the same about cast cranks there... on those days I didn't have any crank, I was just asking ):
http://www.dodgecharger.com/forum/index.php/topic,22274.0.html

note NOTHING IS BEING TOLD ABOUT DIAMETER!

sorry the multiple questions and everything, but more info available, less doubts to everyone and wider options to build anything.
Posted By: moper

Re: cast crank on to 451 stroker - 07/02/09 04:18 PM

My house looks exactly like my brothers. But his is a colonial and mine's a ranch. The deck heights on teh R vs RB are shorter.. That's the distance from the crank centerline to the top of the block on the head surface. So it's the depth (like ANDYF said) that's the issue. You dont have to trust me of any other poster except ANDYF. He has a bunch of very good published articles and I'm sure forgot more than I know. THEY ARE DIFFERENT. I've never been to the Charger site, but on all sites there's a ton of guys who mean really well but might not know all the little idiosyncrasies of these. And many more who say they do and only read and type a lot. I've only built 3 over the years: one with forged factory crank that did not need to have the counterweights cut; one with the 440source RB crank that we did have to cut .200 off; and then one with the 440Source B crank that had a little taper but otherwise dropped in place. If it was available back then I'd have used the 440Source B crank. I'm pretty sure ANDYF has built many more. It's up to you. Try it and see what happens.
Posted By: NachoRT74

Re: cast crank on to 451 stroker - 07/02/09 05:24 PM

yes I have read andyf website and 451 manifesto, but also I can find several info what says based on experience ( like the charger website by Challenger340 ) diameter doesn't need to be touch...

you see ? opposite information, and both are experienced guys.

So, apparently does look only cons on a 451 build with cast crank is the counterweight density for balancing once is cut ? ( no matter if angle grinded for clearence or diameter cutdown for better fit, whatever is the true )

............

then on a "note appart" I'm thinking on 400 rods unless I find locally 440 rods.
Posted By: RemCharger

Re: cast crank on to 451 stroker - 07/02/09 05:49 PM

You can either clearance the block or grind the crank. Personally i'd grind the crank.
As far as listening to expierienced guys... I'd listen to Andy F, as I'm sure most here would. Theres lots of homemade websites out there with all kinds of info...
Posted By: Rug_Trucker

Re: cast crank on to 451 stroker - 07/02/09 06:07 PM

It's been a while. I was thinking of building a lowdeck stroker with a cast crank. IIRC GregZ told me it would take lots of Mallory metal to balance it out.

There is a thread right now on a cast crank slant on www.slantsix.org in theory it should spin up faster etc. Cast is good to 600HP? More than I will ever need!

I am sure there is ways to lighten the cast crank even more?

Go light weight on the rods and pistons?
Posted By: NachoRT74

Re: cast crank on to 451 stroker - 07/02/09 06:59 PM

Quote:

I Cast is good to 600HP? More than I will ever need!

I am sure there is ways to lighten the cast crank even more?

Go light weight on the rods and pistons?




yes, thats why ask about cast crank on stroker ( beside the fact I got for free )... I never have thought on get even closer to 500 HP. In fact I will use stock but ported 452 heads and will keep the 280/474 MP cam ( thats why I choose that cam, to be able to use on both engine assemblies, my actual upgrade project and a future 451 ).
Posted By: NachoRT74

Re: cast crank on to 451 stroker - 07/02/09 07:01 PM

Quote:

You can either clearance the block or grind the crank. Personally i'd grind the crank.





I can grind both, slightly on both, to remove less metal from crank and some on block to not remove a lot from crank, specially because the balancing deal.
Posted By: moper

Re: cast crank on to 451 stroker - 07/02/09 11:20 PM

you call that not cutting the crank? 3/8" off every corner with a 4" grinder? Have a good time.
Posted By: DJVCuda

Re: cast crank on to 451 stroker - 07/03/09 01:16 AM

Quote:

you call that not cutting the crank? 3/8" off every corner with a 4" grinder? Have a good time.




dave - too bad we dont have a talking to the wall smiley...

I've seen a 3/8" angle cut , i've seen mains cut down, but i never saw one drop in. just my personal experience.
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