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Is this a 360 balancer?

Posted By: tmef

Is this a 360 balancer? - 07/14/16 08:21 PM

I came across a project truck that has a 360 that was rebuilt a long time ago but never fired. I took it all apart to see what it had inside, to get the block tanked and the cylinders honed. This was the balancer it had in it. It doesn't have the external counter weight?

Attached picture 0714161120.jpg
Posted By: JohnRR

Re: Is this a 360 balancer? - 07/14/16 08:23 PM

What year is the engine ? I have had some early 70's 360's and they didn't have a balancer like that .

The bad thing with that balancer is once the rubber goes bad enough to allow the other ring to slip the engine will also be out of balance .
Posted By: tmef

Re: Is this a 360 balancer? - 07/14/16 08:27 PM

The cast date on the block is mid 1975.
Posted By: RTshaker

Re: Is this a 360 balancer? - 07/14/16 08:27 PM

yes later 360 balancer
Posted By: 451Mopar

Re: Is this a 360 balancer? - 07/14/16 08:30 PM

That looks like the 360 balancer on my engine. If it is all apart, you could have it balanced with the B&M 360 flexplate, that will allow a larger selection of torque converters.
Posted By: tmef

Re: Is this a 360 balancer? - 07/14/16 10:25 PM

Thanks for the replies guys. Like I said, the engine was done some time ago, I am gonna guess late 90's. Everything inside was dry and luckily he only used engine oil, no assembly lube so it cleaned easier. It is bored .060 over with Silvolite H405P flat tops, J heads with 2.02 intakes and the cheapest timing chain set I think I have ever seen. The cam I rolled over with the dial indicator, lobe lift times 1.5 and came up with what I believe is an old MP 340 reproduction cam, 429/444 lift. It also has an old, very clean Holley Street Dominator intake.
Posted By: tmef

Re: Is this a 360 balancer? - 07/14/16 10:57 PM

My plan is to run that cam with a set of small valve heads and a Performer intake.
Posted By: RapidRobert

Re: Is this a 360 balancer? - 07/15/16 08:45 AM

I would want to find out if it had been balanced. best would be to neutral balance it on both ends so to speak with a neutral dampener then as said you can swap commmon neutral aftermarket converters as desired or with an external dampener he can still neutral balance it for a neutral TC or if he makes it external balanced then use the 10239 B&M scalloped flexplate (for a 904) then you can still use any neutral converter
Posted By: Michael Ecks

Re: Is this a 360 balancer? - 07/18/16 08:31 PM

As already stated it is a late 360 balancer. Not sure what year, but at some point the engineers realized they could remove the old style eccentric weight and hollow out the same amount of material from the opposite side of the outer ring and have the same balancing effect while reducing rotating weight. So, your part is "good-er" for that engine. Double check your pistons, I don't think Silvolite//KB makes the H405P's. If I recall correctly the 405Ps are a stock weight replacement for the 360, so there should be no need to have the engine re-balanced as long as you have the offset weights on the converter or a weighted flexplate.
Posted By: dogdays

Re: Is this a 360 balancer? - 07/19/16 02:26 AM

ABSOLUTELY ON TARGET! Mr. X

OP, If you strip the paint off you may see the damper is marked "for 360 use only" Maybe I'm imagining things.

Anyway the 405P is a Sealed Power stock replacement piston and no rebalancing is needed. I for one would never try to internally balance a 360 unless either:
1. I owned stock in Mallory Corp, or,
2. I had replaced both pistons and rods with parts that weighed significantly less than stock.

This one is a no-brainer.

R.

PS: The 5.0 ford engine has about 3 times the external imbalance compared to the 360 and they manage to run pretty well.
Posted By: tmef

Re: Is this a 360 balancer? - 07/21/16 07:56 PM

The pistons have H405P cast into them and the little "S" inside the shield kind of emblem that I thought was Silvolite. Also "Made in USA" cast into them. Anyway I am not going to do any balancing to it. I just scored a pair of freshly rebuilt 596 small valve heads for it, just need to get the block back from the machine shop and score some A/C, alt brackets.
Posted By: dogdays

Re: Is this a 360 balancer? - 07/21/16 09:31 PM

The "S" is for "Sterling" which is probably the company who made that particular piston many years ago, or else was a trade name.

R.
Posted By: tmef

Re: Is this a 360 balancer? - 07/21/16 10:09 PM

Originally Posted By dogdays
The "S" is for "Sterling" which is probably the company who made that particular piston many years ago, or else was a trade name.

R.


Oh yes, forgot about Sterling. Good to know. Thank you. Other parts with paperwork I got with this truck makes me believe the engine was done in 1997.
Posted By: RapidRobert

Re: Is this a 360 balancer? - 07/22/16 02:00 AM

My H405P's are Sealed Power & are 1.637 CH with 10 CC valve reliefs & were .037" in the hole on my 360
Posted By: Evil Spirit

Re: Is this a 360 balancer? - 07/23/16 08:39 AM

[quote=Michael Ecks]As already stated it is a late 360 balancer. Not sure what year, but at some point the engineers realized they could remove the old style eccentric weight and hollow out the same amount of material from the opposite side of the outer ring and have the same balancing effect while reducing rotating weight. So, your part is "good-er" for that engine.

I wouldn't agree the "scalloped" dampeners are "good-er" for any level of a performance build. The imbalance is moved outside of the elastomer bond, placing more stress on it, and they are prone to the outer ring walking around when used on engines that see much use over 5000rpm, especially as the dampener ages and the elastomer deteriorates. The style with the counterweight cast on as part of the center hub doesn't have that issue, and will keep the outer ring in place in the event of elastomer failure. So while the scalloped dampener may reduce reciprocating weight, IMO it is the poorer choice in the long run - both reliability and safety wise.

In some ways this is a moot point, because a performance build should be running some level of an aftermarket performance dampener.
Posted By: RapidRobert

Re: Is this a 360 balancer? - 07/23/16 04:30 PM

Evil, VG info, I woulda never thought of that! Ma would of had to of had a learning curve like we all do
Posted By: Evil Spirit

Re: Is this a 360 balancer? - 07/23/16 07:08 PM

Originally Posted By RapidRobert
Evil, VG info, I woulda never thought of that! Ma would of had to of had a learning curve like we all do


IMO they went the wrong direction, since they went from the weight on the balancer hub to the earlier ones to the scalloped outer weight on later engines. Probably a cost saving move to pinch pennies.

It's also possible that the engineers saw some type of harmonics advantage to the scalloped style dampener. But any of the aftermarket dampeners that I have seen that have the 360 balance weight - there are a few that are zero balance and you add a cast crank 340 or a 360 weight as needed - it is always mounted to the hub side.
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