internal balance or external 406 balance
Drifting
Joined: Jul 2001
Posts: 1,897
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From: La Fontaine Indiana
Re: internal balance or external 406 balance (ld85)
If you use the 350 flywheel the crank has to be neutral balanced.
Here is how I did mine neutral balanced the crank / flywheel / pressure plate /dampener that way if a have to replace anything just neutral balance it and install. In one of your earlier posts you talked about a blower in the future if you think that you are going to do that then now is the time to prepare for it by going to something better than the stock clutch.
I did away with the dual mass clutch. I bought a centerforce flywheel and pressure plate with the centrifugal weights on it and dual friction clutch it has a lighter pedal than the stock clutch did and is very smooth don't grab or chatter like ceramic just something you may want to consider. :cheers:
Here is how I did mine neutral balanced the crank / flywheel / pressure plate /dampener that way if a have to replace anything just neutral balance it and install. In one of your earlier posts you talked about a blower in the future if you think that you are going to do that then now is the time to prepare for it by going to something better than the stock clutch.
I did away with the dual mass clutch. I bought a centerforce flywheel and pressure plate with the centrifugal weights on it and dual friction clutch it has a lighter pedal than the stock clutch did and is very smooth don't grab or chatter like ceramic just something you may want to consider. :cheers:
Drifting
Joined: Jul 2001
Posts: 1,418
Likes: 1
Re: internal balance or external 406 balance (ld85)
You can use the 350 flywheel with a 12 buck balance plate that goes between the flywheel and the crank. Would still balance the motor assembly though.
BJH makes a 6 inch diameter external harmonic balancer also,it is not certified for race but my BJH balancer has been to 7400 quite a few times and not grenaded ,,,,,,,yet!
Thats the cheapest route,Mallory metal is at a premium these days
BJH makes a 6 inch diameter external harmonic balancer also,it is not certified for race but my BJH balancer has been to 7400 quite a few times and not grenaded ,,,,,,,yet!
Thats the cheapest route,Mallory metal is at a premium these days
Drifting
Joined: Jul 2001
Posts: 1,897
Likes: 0
From: La Fontaine Indiana
Re: internal balance or external 406 balance (mountainmotor)
I'm not familiar with the bjh but if you go with a blower don't buy one with the rubber in it you want one made with all steel hub to drive the blower.
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
Re: internal balance or external 406 balance (black bart)
Hey guys,,,, the builder mentioned a balance plate and basically said that "he didn’t think I would want to hand all that steel" on the crank.
Another buddy I know says that he would balance the crank, pistons, rods, etc as package.
This really has me stumped as to why you can or can not do a certain type of balance,, is it just money difference to do one or the other or are there genuine concerns with a certain method1.
Sorry just relying on the written responses ,.This weekend Iwill get a book this week end and find out the specifics.
Another buddy I know says that he would balance the crank, pistons, rods, etc as package.
This really has me stumped as to why you can or can not do a certain type of balance,, is it just money difference to do one or the other or are there genuine concerns with a certain method1.
Sorry just relying on the written responses ,.This weekend Iwill get a book this week end and find out the specifics.
Burning Brakes
Joined: Sep 2000
Posts: 1,199
Likes: 1
From: NewCastle IN. USA
Re: internal balance or external 406 balance (ld85)
balancing the assembly is a good idea, that means you take your crank, rod's, piston's (ring's too), harmonic balancer, flywheel and clutch/pressure plate to a shop and have everything balanced together.
this can be done to both internal and external setups.
the difference between those two is what you have to keep in mind, the parts are not interchangable (except with the use of an offset weight, but if your buying new parts just get the right stuff to begin with).
the internal balance assembly has the proper weight on the crank throws to offset the piston's, rod's ect.
the external balance assembly does not have all the weight needed on the crank throws, instead it has the extra (offset) weight put on the flyhweel and harmonic balancer.
which one is better? the internal balanced one. but they both work for moderate performance engines.
the external one is subject to more twisting force due to the offset weight hanging on the end's of the crank instead of where it is needed.
RJ
[Modified by ol,RJ, 12:02 AM 12/5/2002]
this can be done to both internal and external setups.
the difference between those two is what you have to keep in mind, the parts are not interchangable (except with the use of an offset weight, but if your buying new parts just get the right stuff to begin with).
the internal balance assembly has the proper weight on the crank throws to offset the piston's, rod's ect.
the external balance assembly does not have all the weight needed on the crank throws, instead it has the extra (offset) weight put on the flyhweel and harmonic balancer.
which one is better? the internal balanced one. but they both work for moderate performance engines.
the external one is subject to more twisting force due to the offset weight hanging on the end's of the crank instead of where it is needed.
RJ
[Modified by ol,RJ, 12:02 AM 12/5/2002]
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Re: internal balance or external 406 balance (ol,RJ)
This will always be a debate-able topic. For sure, the best way I suppose is to have it internally balanced. Only because if it's possible,it's the most foolproof way of doing things. If the couterweights are large enough to balance it all without adding any weight to them, that's great, but not likely in most cases.
If you were likely to be changing things like flywheels etc on a regular basis like a road racing deal and trying to vary acceleration rates for different tracks, then internally makes it a little easier.
But honestly, I don't think it makes much difference for 99% of everything out there. The mallory metal they will have to add to the crank will be done in the end counterweights just to the inside of the front and rear main caps. I don't see a giant difference in adding the weight a little further out to the balancer and flywheel.
I had forgotten about the bolt on weight. They do work and are pretty common. Does the same thing as the tack welded or cast on weight on a stock flywheel
Just depends on how much money you want to spend during the balancing process. I've seen poorly installed mallory metal come out too and it makes a heck of a mess when that chunk hits the block at about 7000 rpm!
Figure that every 454 (including LS-6's and LS-7's)and 400's made were externally balanced. Along with 428 Super Cobra Jets, 460's etc etc etc.
Along with most new 350's (split with extra weight on flywheel only). No big deal.
JIM
If you were likely to be changing things like flywheels etc on a regular basis like a road racing deal and trying to vary acceleration rates for different tracks, then internally makes it a little easier.
But honestly, I don't think it makes much difference for 99% of everything out there. The mallory metal they will have to add to the crank will be done in the end counterweights just to the inside of the front and rear main caps. I don't see a giant difference in adding the weight a little further out to the balancer and flywheel.
I had forgotten about the bolt on weight. They do work and are pretty common. Does the same thing as the tack welded or cast on weight on a stock flywheel
Just depends on how much money you want to spend during the balancing process. I've seen poorly installed mallory metal come out too and it makes a heck of a mess when that chunk hits the block at about 7000 rpm!
Figure that every 454 (including LS-6's and LS-7's)and 400's made were externally balanced. Along with 428 Super Cobra Jets, 460's etc etc etc.
Along with most new 350's (split with extra weight on flywheel only). No big deal.
JIM
