360 magnum. 1 piston lower in cylinder??

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Ya know what.....I think that I am going back to my original, original, original plan when I first bought the motor. Low dollar with good fun factor. I found a build on FABO that I think will fit my needs nicely. I may swap out the pistons if they can get me a little more compression but I may not. I already have the EQ heads with Comp springs, 3.55 gears, 2500 stall converter, Patriot headers, 600 1406 carb. Will use Crosswinds intake, .028 head gasket and H pipe. Of course new HV oil pump, bearings and rings. I may also treat myself to a new Holley 670 street avenger.

Here's what I found:

"Buy a Magnum 5.9/360.........buy EQ CH318b's assembled. Send roller cam for regrind (210/215 @.050" 112 LSA about .475-.490" at valve) Edelbrock RPM intake, stock rebuilt bottom maybe .020" -.030" stock cast pistons etc.. Start, idle will be amazing, expect to smile when foot is above 1/8-3/4 throttle, enjoy 370-400 HP and 430-440 ft/lbs on 87 octane. 360's are the way--tons of torque so you can cruise @ 75mph all day with a sane gear. " Posted by member RAMM.
 
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nm9stheham said:
Or grind out the chambers some. 66 cc's with ICON 742's and a .050" head hgasket getsd you at 9.4- 9.5.

KB362's drop you to 9.1-9.2 with .039" thick head gaskets.
Click to expand...

Those KB362's may be the ticket. IF I am calculating this properly I get almost 9.5:1 with .028 gasket and the piston/pin weight is 616 grams vs stock 610.
There is a notation on KB's website that says:
Piston may protrude on 1992 and up Magnum truck blocks. Magnum rod must be narrowed to 1".
I'll have to contact them and find out what that is all about.
 
Another set-back? Today I weighed the piston/pin/rod assemblies (no rings) that I removed from my 360 Magnum. The number eight assembly is from a donor vehicle and replaced my original that had the bent rod. The piston is also not usable due to damage from my removal from rod. The weights in grams are as follows:
1- 1401 2- 1406
3- 1405 4- 1404
5- 1405 6- 1399
7- 1402 8- 1394

Since the difference between number five and six is close to seven and replacement #eight, I should be good to go. Correct.
Should I swap six and seven or five and eight to balance out?
I will be using new rings and bearings of course.
This was a low mileage, good running motor even with rod benty.
 
Well, that is not the way to work out the bobweight which is what is used to figure up balance. Actual bobweights that would result from correct weighing of the individual parts would yield different numbers.... the overall set might have more or less max to min variation.

But, what you are showing is that none of the combinations are way outside of a reasonable tolerance relative to each other, and very probably are within factory tolerance.

Your best guess at best balance would be to match the lightest set with the heaviest. But I seriously doubt it is going to make any difference for this type of build.
 
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