My 360 build.

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Maybe...but if they are lightening it, they are removing metal correct?
I've never heard or seen a balance quote on a piece of paper. So I cant say one way or another. I can only imagine that there is a fair amount of calculations and weighing involved, which equals a lot of time=$$
RustyRatRod said:
We wish! Mallory metal now has far eclipsed the cost of labor. It's ridiculous.
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4spdragtop said:
Maybe...but if they are lightening it, they are removing metal correct?
I've never heard or seen a balance quote on a piece of paper. So I cant say one way or another. I can only imagine that there is a fair amount of calculations and weighing involved, which equals a lot of time=$$
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Well it depends, Steve. They may need to remove metal from one side and add to the other. It's all about gettin the bob weight right. Sometimes it's a trick.
 
Wyrmrider said:
OK
my 2 cents on the balance
you balance 100% of the rotating weight- you are not changing that
you only factor in 50% (or so) of the reciprocating weight
which is the rod small end, piston, pin, rings
not an exact science
so what? 50% of the difference in piston weight?
so you end up overballanced a little figure out how much
what impact does an overballance that size make
who overballances Dilibertly and why?
in which plane would any overballance shake be felt- H or V
would motor mounts hide?
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FWIW...... 50% of the piston weight change is doubled because there are 2 piston/rod assemblies represented by each bobweight. So, if you're thinking of it in that fashion, then think of 100% of the piston weight change going into the bobweight.

The over- or under-balance creates a rocking motion in the engine at the same rate as the RPM's. Imagine passing an imaginary axle through the #3 main bearing, and the engine rocking back and forth on that... .front is going up while rear is going down and vice versa, back and forth once per crank rotation. The trannie and its mounts tends to limit this rocking motion, but then those forces all go into the front and rear of the bearings, crank, block etc.

The balancing of the piston/rod assemblies minimizes a different imbalance around the main axis of the crank.
 
4spdragtop said:
Maybe...but if they are lightening it, they are removing metal correct?
I've never heard or seen a balance quote on a piece of paper. So I cant say one way or another. I can only imagine that there is a fair amount of calculations and weighing involved, which equals a lot of time=$$
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I've already posted...the math is simple. Takes no time.
 
4spdragtop said:
Math might be simple, but the time it takes to come up with numbers to plug in??
Gotta weigh every single piece right?
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Yes. But I seperate out the math from the time to weight and equal each part. Today we are pretty lucky. Most Pistons and rods are now well within a gram. So you are really just making sure something from a different run didn't get boxed together.

Once you have the big end, pin end, piston, rings, pin, pin retaining clips and a rod bearing weighed, you take about 5 minutes to add up the bobweight.

Then the real work begins.
 
I really wish the crank manufacturers would make cranks unbalanced for machine shops, especially the cast versions. I hate when you need to add weight right where they drilled a hole. Usually this is on stuff with hyper pistons and cast cranks.
 
FWIW...... Getting the end weights for stock rods matched can be time consuming.
They will vary a fair amount. Checking 1 set of light SBM rods yielded bobweight variation of over 20 grams across the set if the piston and pin weights were all identical. So yes IMHO, lots of labor there.

And for info.... The rod end weighing part is the area most subject to errors.
 
I agree, but what RRR is saying is that IF you need to add metal...... I don’t think anybody will give a quote on the dollar amount and much less stock to it. Typically, I get, it starts at $ *** ....

4spdragtop said:
Maybe...but if they are lightening it, they are removing metal correct?
I've never heard or seen a balance quote on a piece of paper. So I cant say one way or another. I can only imagine that there is a fair amount of calculations and weighing involved, which equals a lot of time=$$
Click to expand...
 
89on35s said:
I can't remember who, but someone I was talking to out at the track recommended Precise Engines to me for my Car engine stuff. I have used them in the past, but it was for Snowmobile stuff. @79410aspenrt do you have a recommendation?

Cley
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i have used Precise Engines in the past. i don't think i will go back there. i recommend Bruce from ABS in regina. but he's a one man show and it takes time, lots of time. i have used Northside Engines for some small stuff.
 
Was it a particular issue with Precise? I know they are expensive but I have been happy other than that.

Cley
 
I guess it all depends if u want to ship or travel. Yes, Bruce is the best. I hear Northside does good work but I haven’t used them. Kim
 
this is what i get from the machine shop along with the bill....print out of the balance job...plus he keeps one on file for the future should something needs to be fixed. This a 360 .070 small block cast crank that had been previouly internally balanced. New pistons weight pretty close to old pistons but went from a 660 gram H beam rod to a 595 gram I beam rod. Weight had to be removed from the crank....I wonder if i could have gotten a rebate on the mallory metal...lol

20171031_210729_resized.jpg
 
I can not find the second sheet where they spin it and shows the numbers.....
 
Well I got it tore down completely now. I'm going to follow along with @krazykuda and his awesome how to that he was kind enough to put together. So far the crank bearing surfaces look awesome. Both the crank and bearings are marked .010 so I know what main bearings to get now. The rod bearings are not marked but I can read the part number. I have yet to try and find what they are.
20191201_151035.jpg
20191201_151043.jpg

The bores look good at .030 over. I'll hone them up and drop new pistons in with the stock rods and ARP rod bolts. I ordered most of the stuff I need like pistons, rod bolts, oil pump, etcon Summit's black friday sale saving a whopping 50 bucks but free shipping to Canada is always sweet!
20191201_155400.jpg

If anyone wants a used MP 508 cam it's out and available too.
20191201_160614.jpg

Looks like a new double roller in it so that is a bit of a bonus too! All in all it was a good couple hours in the shop!

Cley
 
89on35s said:
Well I got it tore down completely now. I'm going to follow along with @krazykuda and his awesome how to that he was kind enough to put together. So far the crank bearing surfaces look awesome. Both the crank and bearings are marked .010 so I know what main bearings to get now. The rod bearings are not marked but I can read the part number. I have yet to try and find what they are.
View attachment 1715431446 View attachment 1715431447
The bores look good at .030 over. I'll hone them up and drop new pistons in with the stock rods and ARP rod bolts. I ordered most of the stuff I need like pistons, rod bolts, oil pump, etcon Summit's black friday sale saving a whopping 50 bucks but free shipping to Canada is always sweet!
View attachment 1715431448
If anyone wants a used MP 508 cam it's out and available too.
View attachment 1715431449
Looks like a new double roller in it so that is a bit of a bonus too! All in all it was a good couple hours in the shop!

Cley
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If there are no size markings on the bearings, they are usually standard, however I would recommend measuring the journals to be sure....
 
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I've got 2 sets of stock rods and the ones in my car as well. Is there a benefit to new rods?

Cley
 
Good to know! If you're in town some time you should stop by for a Christmas drink and give me a second opinion on what I have!

Cley
 
oldkimmer said:
Cley, u can buy new rods on Speedmaster 79. For less than $200.00
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89on35s said:
I've got 2 sets of stock rods and the ones in my car as well. Is there a benefit to new rods?

Cley
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89on35s said:
Good to know! If you're in town some time you should stop by for a Christmas drink and give me a second opinion on what I have!

Cley
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However, I prefer to use rods with oil squirt holes and many of the aftermarket rods do not have them... That's why I prefer to recondition old rods and have new bolts installed so I can have squirt holes....


but if you don't want oil squirt holes then look into new rods...
 
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