**** 360 Piston Options ****

Here are the options for Sealed Power/Speed Pro:



The Speed Pro 405P40

Comp dist = 1.576"
Piston dish = 3.140" dia x .0705" depth

The piston compression distance is slightly taller than my starting point of 1.572" from the pistons that came in it...

1.576 - 1.572 = .004"

.004" x 12.819 in**2 = .05 in**3 = .84 cc

The dish is:

Pi/4 x Bore**2 = .7854 * (3.14)**2 = .7854 * 9.860 in**2 = 7.74 in**2

7.74 in**2 x .0705" depth = .546 in**3 x (16.387 cc/in**3) = 8.9 cc

So take the 8.9 cc dish and subtract the .84 cc's from the increased height and you get 8.06 cc increase...

My original volume above the piston at 1.572" was 34 cc (measured in previous thread)

So my new volume above the piston is 34 + 8.06 = 42.1 cc

This brings my Clearance Volume to:

42.1 + 12.4 + 69 = 123.5 cc

Therefore the compression with these pistons will be:

(123.5 + 752)/123.5 = 875/123.5 = 7.09


View attachment Sealed Power 405P40 B.jpg

http://www.summitracing.com/parts/slp-w405p40/overview/make/plymouth


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The next Option is the Sealed Power WH405CP40

Comp dist = 1.576"
Piston dome = + 10 cc

So for the compression dist:

1.576 - 1.572 = .004"

.004" * 12.819 in**2 = .0513 in**3 (16.387 cc/in**3) = .84 cc increase

Now add the 10 cc for the dome height:

.84 cc + 10 cc = 10.8 cc


Now adjust my old area above the piston for this:

34 cc - 10.8 cc = 23.2 cc

Now my clearance volume becomes:

69 + 12.4 + 23.2 = 104.6 cc

This will make the compression:

(104.6 + 752)/104.6 = 856.6/104.6 = 8.2


View attachment Speed Pro WH405CP40 B.jpg

http://www.summitracing.com/parts/slp-wh405cp40/overview/make/plymouth


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The last Sealed Power/Speed Pro option is the Speed Pro H116CP40:

Comp Dist = 1.660"
Piston Dome = + 5 cc

The increase in compression distance:

1.660" - 1.572" = .088"

.088" * (12.819 in**2) = 1.13 in**3 (16.387 cc/in**3) = 18.5 cc

Now we add the dome volume to the increased compression distance:

18.5 cc + 5 cc = 23.5 cc

Now adjust my volume above the piston:

34 cc - 23.5 cc = 10.5 cc

This will bring my clearance volume to:

69 + 12.4 + 10.5 = 91.9 cc

This will bring my compression to:

(91.9 + 752)/91.9 = 843.9/91.9 = 9.18


View attachment Speed Pro H116CP40 B.jpg

http://www.summitracing.com/parts/slp-h116cp40/overview/make/plymouth