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360 balancing.

Posted: Thu Feb 09, 12 1:16 pm
by Anonymous
Hi moparFolks,

In a strange way I think the problems that are associated with external balancing of 360's and cast-crank Bigblocks have stopped folks wanting to use them in the past.
There is nothing wrong with cast-cranks and I have never heard of anyone breaking one in a street engine.
Its just a changeover issue when you go from internal balance set-up to external.
The engine should have the damper already fitted and its only the flexplate, converter or flywheel that's the 'fly in the ointment'.
A cast crank 340 uses a different converter to a 360 (but cast crank 318 is internal).
A sixpack 70/71 engine also uses a special converter, different from the cast-crank converter for 383's(71 only)and the cast-crank 400/440's, different again!

The information is out there, on da tinternet and just needs deciphering L0L.
HH

Posted: Thu Feb 09, 12 4:34 pm
by db
I've been wading through it for the last few days... :roll:

I'm learning how to I.D. your flywheel.

360- Cast crank. Externally balanced. Has 3x 1 13/64" holes, see pics...

Posted: Thu Feb 09, 12 5:22 pm
by db
ALL V8 flywheels have 2 mounting bolts closer together.
SLANT 6 ones are evenly spaced.
Hemi and race types usually have 8 bolts

ALL B.B. (except 440 cast crank), ALL 318 and early 340 FORGED crank motors are internally balanced and use a NEUTRAL BALANCED FLYWHEEL.
FROM MID 1972, 340's changed to CAST CRANK with external balancing. The Flywheel changed to EXTERNALLY balanced, but NOT THE SAME AS THE 360. The holes are different- these have 3x smaller holes near the outer edge instead.

130-tooth flywheels are for 10.5 or 10.75" clutches.
143-tooth flywheels are for 10.75 or 11" clutches.

Please correct if needed or add to this (more pics would be good), I'm only going by my intrerenet reasearch... ;)

Posted: Thu Feb 09, 12 6:03 pm
by Cannonball
db wrote:ALL V8 flywheels have 2 mounting bolts closer together.
SLANT 6 ones are evenly spaced.
Hemi and race types usually have 8 bolts

ALL B.B. (except 440 cast crank), ALL 318 and early 340 FORGED crank motors are internally balanced and use a NEUTRAL BALANCED FLYWHEEL.
FROM MID 1972, 340's changed to CAST CRANK with external balancing. The Flywheel changed to EXTERNALLY balanced, but NOT THE SAME AS THE 360. The holes are different- these have 3x smaller holes near the outer edge instead.

130-tooth flywheels are for 10.5 or 10.75" clutches.
143-tooth flywheels are for 10.75 or 11" clutches.

Please correct if needed or add to this (more pics would be good), I'm only going by my intrerenet reasearch... ;)
well get yours Bananarama! machined and get the Bananarama! ohn with it all this Bananarama! wasted time when yours will Bananarama! do the job its not Bananarama! rocket science to many Bananarama! chefs get the Bananarama! on with it i am Bananarama! done with this Bananarama! Bananarama! now, :roll: :roll: :roll: :twisted:

Posted: Thu Feb 09, 12 6:08 pm
by db
:D

Well put :thumbright:

O'course I can't do bugger all for a couple of weeks now cos of the op :roll:

Posted: Thu Feb 09, 12 6:53 pm
by autofetish
Cannonball wrote: well get yours Bananarama! machined and get the Bananarama! ohn with it all this Bananarama! wasted time when yours will Bananarama! do the job its not Bananarama! rocket science to many Bananarama! chefs get the Bananarama! on with it i am Bananarama! done with this Bananarama! Bananarama! now, :roll: :roll: :roll: :twisted:
And post of the month goes to duncan :thumbright:

Posted: Thu Feb 09, 12 7:30 pm
by Anonymous
Good use of Bananas there Duncan!

Please show results of your Flywheel mods as it will be UNIQUE here in the UK, and maybe do a couple more whilst the mill is set-up LOL! :thumbright:
If you get any change outta a £100 you is a lucky man after ALL!!! :D

HH

Posted: Thu Feb 09, 12 7:34 pm
by Anonymous
Hi db again LOL!

Once you get your MOT done you can drive the wonderful Belvedere down to sunny Kent and I will gladly remove your crankshaft, rods and pistons and rebalance the whole KIT and Caboodle at a very special Moparmate rate! :thumbright:

Best wishes HH 8-)

Posted: Thu Feb 09, 12 8:22 pm
by db
Thats splendid of you Mr Bacc but it would suck around £250 in juice just to get there :shock:

If no-one else has done it I'm DEFINITELY doing it :D

Posted: Thu Feb 09, 12 9:41 pm
by Les Szabo
don't see what all the fuss is about.....my 6-pak bottom end (externally balanced orig, steel crank) was all internally balanced with the damper B&M flexplate and everything else needed for balancing, everything was weight matched first, I spun that slugger to 7500rpm, it ticked over like a stocker and run real sweet....sold it on in 1 piece...by the right parts and balance it internally...job done no?

Posted: Thu Feb 09, 12 9:53 pm
by db
Oh Les, what have you just walked into :roll:

Some strong opinions will be along shortly...

Posted: Fri Feb 10, 12 12:14 pm
by Les Szabo
db wrote:Oh Les, what have you just walked into :roll:

Some strong opinions will be along shortly...
Hi db, no mate, don't bother me at all, thats what this Forums for, discussion and opinions..and just giving mine.....were all grown up here!.....just saying what I did when I built my engine and that took 175hp of sniff = 640+HP and 7500rpm and stayed together and ran real sweet :thumbright:....
unlike the £3000 engine I bought from another source which you all know about :deadski:

Posted: Fri Feb 10, 12 1:39 pm
by db
:lol:

My motor's gonna remain as-is, at least until something goes bang.

We're pulling it out Sunday to whip out the flywheel and it's off to my mate for drilling.
This will make some readers happy, some not so... ;)