All the new cranks I've seen for 383 seem to be external balanced unless you go to recommended 6.00 rods. For 5.7 rods can an externally balanced crank be "made into" or used and the assembly still be balanced internally?

 

The reason for that is the weight needed internally, to balance it. The 6" rods allow for increased counterweight size due to additional piston clearence at BDC. You might want to do some more shopping. I can't cite specifics, but I believe internally balanced cranks are available for shorter rods. *I* have 4.00" stroke crank (383 is 3.75") swinging 5.85" rods. If you can't find it to buy, you CAN have such a crank internally balanced, with mallory heavy metal.

What is the objection to the 6" rods? If it is price, the rods will likely cost less than the re-weighting (with mallory) of the the crank.

RACE ON!!!

 

I already bought pistons for 5.7 rods but really would like internal balanced to save HB and flywheel for easy swap out and I'm willing to spend the extra $.

 

I understand the dilemma. Can the pistons be exchanged? Most of us on here prefer the long rods. Otherwise, contact some crank manufacturers. Some will definitely be able to accommodate your wishes. Callis and Cola, specifically, first come to mind.

RACE ON!!!

 

:lolg: Dude! SCAT cranks are right next to you in Redondo Beach http://www.scatcrankshafts.com. David Vizard, the Wizard, says SCAT cranks even though cast are great improvements over stock cast pieces. Better metal, much improved machine work and very high quality control. Good to over 500+ hp and high rpm too. And this site http://www.furiousracing.com/parts/crankshafts sells'm for various applications/rod lengths for $280.
And yes you what an internaly balanced crank that matches your rod piston reciprocating weight. You can spend a bundle of money to balance an expternal balance type crank with the heavy metal nonsense. But then you need to find a flywheel balanced to match your internaly balanced external style crank - more headaches.
So give SCAT a call - or even go and give'm a visit - to tell'm what you want/need for your application. :thumbs:
Good luck and keep us posted. cardo0

 

:shocked: :shocked: :shocked: ?????? It sounds like somebody's confused!

:rolleyes: :rolleyes: :rolleyes:
That LAST sentence, is a lulu!
.


[Modified by CFI-EFI, 9:21 AM 5/23/2004]

 

:lolg: Lulus? Is that when you make suggestions without parts numbers or pricing to support what you recommend? And how much does adding heavy metal to balance a crank cost? Machine shop prices I know of are $50 to $100 for just labor. But why not, its someone else that has to pay the bill. Advicing someone to spend more money on the wrong crank sounds like a real lulu to me. I guess there's no spending limit when your in lululand.
So how about some lulu advice(?) for a flywheel to match this external balance crank which is going to be internaly balanced? Part numbers? Prices? And type of rear seal? Or is someone suggesting installing a one piece rear seal crank into a two piece rear seal block?
Again more cost/expensive (for someone else) and time/delay. Or in lululand are there one and two piece rear seal cranks that fit both internal or external balanced motors? Again part numbers/prices please? Or maybe someone just dosen't know what their talking about. I guess that doesn't matter much when your in lululand.

 

If the rotating assy is internally ballanced you can use any flywheel that's netural ballance - I.E. 350's 327's..
Much easier to get a deal on a 350 flywheel.

 

Life, for you would be much easier if you could read, comprehend and respond in kind. *I* never suggested be use an internally balanced set up. He did, and you even quoted him saying so. I realize internal balancing is expensive. That is why I first suggested that he might try to exchange the pistons, and go to the longer rods...To keep the costs down. What crank do you see me "Advicing" him to buy, and why is it "the wrong crank"? You're kidding with this one, right??? He uses his stock flywheel! *I* haven't seen the seal situation addressed. Are you saying I recommended something that hasn't been discussed? I can't speak for where ever you're coming from, but in the real world, YES. Absolutely! And you know him well. Take a breath between snorts or puffs and join the real world.

WOW!!!

 

:lolg: "The reason for that is the weight needed internally, to balance it....If you can't find it to buy, you CAN have such a crank internally balanced, with mallory heavy metal."

Someone needs an eye examine as he can't read his own writing. Or maybe in lululand stating what someone can do (add heavy metal) isn't a recommendation - just more useless nonesense. :bs And BTW if some don't understand the externally balanced cranks for the 350" are fit the '86 & later one piece seal motors and require a flywheel with different bolt pattern. Any 350" neutral balance flywheels for the one piece seal ('86 & later) cranks for sale? Part numbers and prices please. I will admit I don't know but suspect not. And yes, if whe're talking external balance cranks ("All the new cranks I've seen for 383 seem to be external balanced unless you go to recommended 6.00 rods") are of different flywheel bolt pattern except for the 400" externaly balanced cranks - but we are talking "new" cranks here.
"You're kidding with this one, right??? He uses his stock flywheel!"
Well unless Surfer69 had a 400" motor his 350" flywheel won't cut it - or not for long. :lolg:
quote: And type of rear seal? Or is someone suggesting installing a one piece rear seal crank into a two piece rear seal block?
"*I* haven't seen the seal situation addressed. Are you saying I recommended something that hasn't been discussed? "
Sounds like someone fell off his wagon and can't remember that a '69 has an two piece rear seal for an internal balanced crank with a different flywheel bolt pattern than the external balance cranks. Yes the external balanced type replacement type crank that Surfer69 inquired about. The one someone denies any recommendation of balancing with expensive heavy metal - just BS'n about it I guess. :bs

quote: Or in lululand are there one and two piece rear seal cranks that fit both internal or external balanced motors?
"I can't speak for where ever you're coming from, but in the real world, YES. "
Again a recommendation from lululand without part numbers and prices. :p:
BTW thanks for the spellchecker. To bad lululand can't spell *I* like the the rest of us - I. :p:

 

Yes, but it will require heavy metal to be installed into the crank, (see posts above) which may be high-dollar. If you really want to go internal ballance it may be cheaper to sell what you already have & start fresh with an internal ballance kit.
:cheers:

 

Before I critique your continued non-sequetor ranting, let me clear up a misconception you evidence. One piece seal, '86-up cranks DO have a slight imbalance in the rear only that is compensated for with additional weight on the flywheel. The 383 uses a 400 based crankshaft. ALL 400s are externally balanced with unbalanced flywheels and dampers. The amount of added weight on a one piece seal 350 crank is very small compared to that of a 400. Because the 3.75" stroke 400 crank has insufficient internal weight to effect a proper balance, the most economical 383 stroker kits spec that 400 flywheel and damper be used. THAT is the common external balance 383. It has nothing to do with the 1 piece seal, later model, imbalance. No, 400 Chevy engines were ever produced with 1 piece seals. Because of the external weighting required for the 400, any 383 internally balanced engine must have heavy metal inserted into the counter weights of the crank to be internally balanced. If our post originator wants an internal balanced 383, it will have to have heavy metal in the counterweights. With heavy metal, internally balanced, it becomes, balance wise. the same as a pre '86 two piece seal 350, in that it takes neutral balance flywheel and damper. He can use his old parts with an internally balanced 383 stroker kit. In your following quote from me, you have joined statements I made on two different aspects, into nonsense. The underlined snippet, is an explanation to him, why many kits require a 6" rod with their internal balance kits. It is for piston the counter weight clearance. The italicized portion, is where I was explaining a way to utilize a shorter rod. If you are going to criticize my writings, you're going to have to read and understand them, first. I DO make mistakes, but you haven't found any. Here you mistake the only solution for a "recommendation". I am merely trying to assist the gentleman achieve his goals. If you have a better solution, lets hear it. Is that supposed to be English? A bad translation, maybe? If it means what it think it might, remember that the slightly imbalanced 1 piece seal 350 is a totally different thing than an externally balanced 383. With the subject vehicle being a C3, how did the one piece seal cranks ever get into the discussion? Probably, but they are not germane to the subject. Who cares? I have NO idea what you're trying to say, there. Back to basics. An internally balanced 383 uses the stock, pre 1986, neutral balanced, flywheel and damper. An external balanced 383 uses the stock 400, unbalanced flywheel and damper. Easy, HUH??? I never forgot that a '69 has a two piece seal. YOU are the one that tried to complicate the issue with seal type. Here it is evident that you are confusing an internal balance and an external balance with a mandated seal difference. Taint so. I wasn't necessarily recommending it. But it IS the only way to internally balance a 383 crank. Asked and answered. Again, not germane to the discussion, and NOT a recommendation. I may research part numbers if and when it serves a purpose. If YOU won't believe me without part numbers... Who cares? It IS a matter of fact. Goodness!!! Look who's criticizing spelling and grammar. I've been kind enough to NOT insult your literacy to this point. I shall continue to hold comment on your literacy general intelligence, AND knowledge of the 383 stroker kits. Your own words speak volumes. Wise up.

 

:nonod: Well I looked and that non-sequetor word isn't in my dictionary. And I don't see any value in debating the rest of your nonsense. Nor will I waste my time on your lulu mentality - it is more valuble than that.
I sent Sufer69 to the right place for the right part at a descent price. Match that or shut-up! :lol:

 

It isn't in my dictionary, either, but you DO recognize what language it is...Right? I find it VERY interesting you are using a dictionary to try to figure out what I'm writing. A little over your head??? It IS a waste of time debating, because, unlike you, *I* (oops! more fodder for your spell checker) DO know what I'm talking about. Not only do you not know what you're talking about, you can't tell what I'm talking about, even WITH a dictionary. You DID give him some good references, but bad info. I more that matched that, partially by dispelling some of the falsehoods you tried to spread. Also, by helping him understand why things are as they are. "Shut-up!"??? I'll hold my tongue, on that one.

 

I bought a Scat 3.75 stroke internally balanced crank for 6 inch rods, and still had to add Mallory heavy metal to balance it properly for my nuetral balanced flywheel and dampner. What they advertise is not neccessarily what you get. It could have been my combo, but it is nothing out of the ordinary. It has held up to 500 hp and torque though.

 

Well, I leave for one day and return to this? :lol:

I did talk to Scat a while ago and I did know they are right here. Adding the mallory to an external crank was mainly what I was thinking about. The pistons cant be returned and I personally dont like the pin in the oil groove thing with the 6 in rods. I wanted internal which is better on the bearings and overall better performance.

So I need to ask if a ground 400 crank could be internally ballanced?

Also SKID, that's interesting about having to rebalance an "internal" balanced crank. I think I would have asked SCAT why that happened.

 

You missed all the fun. Cardo0's heart is in the right place. He is simply misinformed and doesn't care to listen. I don't think he is the sharpest knife in the drawer.

A 383 crank, IS a ground 400 crank. That is the origin of the 383. The 400 main journals are turned down to fit the 350 main bearing saddles. Whether it's actually a modified 400 crank or a new piece intended for a 383, that IS what it is. All 400s are externally balanced and have 2 piece rear main seals. The seal type has nothing to do with internal or external balance on a 400/383. Because the 400 is externally balanced, the base 383 kits require the use of the unbalanced 400 flywheel and damper. The ONLY way you will be able to achieve an internally balanced 383, is with the use of heavy metal. As pointed out, that isn't particularly inexpensive, but it's necessary for an internal balance. There are several good reasons to go to internal balance, if it is within your budget. It can. Detailed above. I can guess how that happened. I presume he bought a crank with heavy metal, an internally balanced crank, that wasn't balanced specifically, to HIS rotating assembly. If his pistons and rods were heavier than the mfg, guessed, additional weight would have to be added. If you DO decide to spring for the internal balance, talk to the seller and arrange to send them YOUR parts for an accurate, final balance.

One final note. You used the term "flywheel". I assume you have a manual trans. IF you should decide to go the more economical, external balance route, be advised that an unbalanced, 400, flywheel won't fit your bell housing. All 400s used 168 toothed flywheels/flexplates. The flexplates fit Corvette housings, the flywheels, don't. You would require a special balance job on your flywheel, or a specialty flywheel, intended for that application to use an unbalanced crank, with a stick shift. The 168 toothed flywheels/flex plates require a different starter or at least starter nose piece. As you noted, all that is avoided with an internally balanced assembly.

I hope I haven't included too much. If something isn't clear...ask.

RACE ON!!!

 

thanks for all the help, I'm learning on the fly here. So it sounds like I need to check my (yes) flywheel which I thought was a 168 tooth already, but I will double check. And internal is the way to go then to avoid these problems.

I called my local shop and its around 400 to internal balance new crank. More to do used 400 crank because of the extra journal turning. They said 35 bucks a slug of mallory.

External was 150 but the flywheel situation messes everything up. New custom steel flywheel plus balancing would end up around the same 400.

So I probably will just cough up the extra $ and go internal anyway.
I have to do some thinking about the flywheel.

 

Absolutely, DO count your flywheel teeth. My info is more C4 and later models. If you have the 168 toother rather than the 153 tooth, it changes your options, and therefore costs. Do you happen to know off the top of your head if the two bolts mounting your starter are straight across, forming a line perpendicular to the crank? Or if they are staggered, one further forward than the other?

RACE ON!!!

 

The crank had no Mallory as purchased, but believe it has heavier counterweights. I have 6" Eagle H beam rods and SRP forged pistons. I don't think they are abnormally heavy parts. My balancer guy says he sees it all the time with the "cheap" cranks.