360 balancing.

Anonymous · Post by **Anonymous** » Thu Feb 09, 12 1:16 pm

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

db · Post by db » Thu Feb 09, 12 4:34 pm

I've been wading through it for the last few days...

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

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

db · Post by db » Thu Feb 09, 12 5:22 pm

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...

Cannonball · Post by **Cannonball** » Thu Feb 09, 12 6:03 pm

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,

db · Post by db » Thu Feb 09, 12 6:08 pm

Well put

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

autofetish · Post by **autofetish** » Thu Feb 09, 12 6:53 pm

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,

And post of the month goes to duncan

Anonymous · Post by **Anonymous** » Thu Feb 09, 12 7:30 pm

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!

If you get any change outta a £100 you is a lucky man after ALL!!!

HH

Anonymous · Post by **Anonymous** » Thu Feb 09, 12 7:34 pm

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!

Best wishes HH

db · Post by db » Thu Feb 09, 12 8:22 pm

Thats splendid of you Mr Bacc but it would suck around £250 in juice just to get there

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

Les Szabo · Post by **Les Szabo** » Thu Feb 09, 12 9:41 pm

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?

db · Post by db » Thu Feb 09, 12 9:53 pm

Oh Les, what have you just walked into

Some strong opinions will be along shortly...

Les Szabo · Post by **Les Szabo** » Fri Feb 10, 12 12:14 pm

db wrote:Oh Les, what have you just walked into

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

....
unlike the £3000 engine I bought from another source which you all know about

db · Post by db » Fri Feb 10, 12 1:39 pm

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...