Does anybody know the cc displacement of stock 360 Pistons? Also, how deep are they usually in the bore? Thanks

you mean how many cc's is the dish? there usually 70-80tho down in the bore.

CC's of the dish? If the short block is right in front of you on a stand you could set a thin steel scale across the piston & measure the dia of the dish (A) and slip feeler gauges under it for the depth (B) then 3.1416 X (1/2 of A) squared X B (ie .050") X 16.387064 for the area in CC's or wait for someone to post who has that # handy. Several stock 360's I did the pistons were ~ .100"ish down in the hole (not good).

yes, I was wanting the cc's in the dish

Just the dish of the piston was 11cc's? Wow, I was thinking around 7 from the little info I could find. Thanks

BTW, how far down in the hole is the 2003 360 piston?

I think the LA piston dish is ~8cc.

mine were .080-.1 in the hole of my old motor...still ran strong with a comp XE262 though

I also measured 11 cc's average from 8 pistons from a 1994 Magnum 5.9 V8.

In the 'Magnum Manifesto' article from 1998 Hot Rod Magazine they list what appears to be an official number of 11.20 cc's from Mopar Performance.

Official compression height of those pistons may be 1.622 inches.

I measured 1.626 inches

In the 1995 FSM there is an error in the specs for the 360 V8, where they incorrectly give the piston weight and drawing of the pre-Magnum design, but correct piston drawing and spec's are given for those same Magnum pistons in the V10 spec's section.

Willem Weertman's book confirmed that at least the first years of the 8L iron V10 used Magnum 5.9L V8 pistons as a cost saving measure.

How far down in the hole on a Magnum 360 did you measure or do you know a magnum's official deck height? I can figure it out if I know that using the compression height.

I just measured the CCs of my 72 360 with the pistons at TDC and grease in the ring grooves to seal them and no decking on the block and measureing the total volume in the cylinder I found 30 CCs in there

I didn't measure the piston dish or how far down the pistons were in that motor, on a 97 360 however I find the pistons are .070 down.

30cc, but...how far down in the hole are they dave? 4" bore, .1" down in the hole is 20.6cc. you need to subtract that volume, and probably another 1 cc or so for the crevice volume (beween the piston and the wall above the top ring land) from dave's measurement to get the dish volume.

I've got a '72 I'm playing with and the non-dished pistons are about 0.110" down the hole. This calculates to 22.7cc. All the '72's I've looked at had no dish.

Quote:

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I just measured the CCs of my 72 360 with the pistons at TDC and grease in the ring grooves to seal them and no decking on the block and measureing the total volume in the cylinder I found 30 CCs in there

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The "Magnum Manifesto" article from Hot Rod magazine
and various years of the Mopar Performance catalog list a deck height for the Magnum 5.9 V8 as
9.585
and the Magnum V8 MLS design head gasket compressed thickness as
0.0475

It seems to make sense
considering the old LA V8
deck height spec of
9.599
and later head gaskets of
0.033

When they decided to increase the head gasket to MLS type thickness they milled down the block to compensate?

Blueprint spec for a
Magnum 5.9 V8
might be

09.585
-6.123
-1.622
-1.790
--------
00.050 in hole
+0.0475 gasket thickness
--------
00.0975 quench clearance

Why so bad when 0.026 to 0.060 quench is widely declared to be is what is desired?

The Honda V-Tec factory quench clearance is supposed to be 0.75 mm (0.0295 inches)

Quench clearance on the Magnum 5.9 V8 might be that high and "bad"
in order to reduce unburnt hydrocarbons and carbon monoxide levels during the 'cold start' part of the EPA test.

Chrysler may have had to reluctantly increase the quench clearance until the cold start test could be passed.

We know that they had problems with the cold start HC and CO on the 1994 Magnum 5.2 V8 because they reduced the internal size of the exhaust manifolds and Y pipes to keep the exhaust gas from cooling so much as it expanded as it left the exhaust port. This cooler exhaust gas was failing to heat the catalytic converter up fast enough during cold start. You may have heard about the 5 hp penalty from these smaller exhaust manifold passages compare to the 1992-1993 original design.

When quench pads are working 'right' it does cool down and even snuff out a considerable percentage of the last fraction of the air and fuel mixture to burn, and this effect is greatest when the metal walls are dead cold

If anyone has typical factory 'variances' on
block deck heights,
connecting rods,
strokes of crankshafts,
please post them.

In the past crank grinders have posted that the Chrysler crankshaft tolerances were loose, both on stroke length and proper angle

I have pulled TONS of heads off magnum motors and never seen anything but a graphite type head gasket and NEVER a MLS.

As for the lousy quench thing I think it was because they were too lazy to step up the machining quality where they could consistantly run it real tight.

MLS gaskets are made for iron/AL head motor combos that have different thermal expansion coefficients, MLS allows the AL head to slide when it expands, that is why the RA of the head needs to be like 16, very smooth so the gasket doesnt hang up. My pre magnum 360 (last year for 360) had the slugs in the hole .090 and the dish was 8cc.

Well, what would you call the 1992 design of the thicker factory Magnum head gasket
... composite or impregnated fiber, maybe?

It certainly is not old style metal shim.

http://www.dupontelastomers.com/Applications/Automotive/head.asp

I don't know what they are called but they are really flakey stuff like soft flexible graphite stuff with a one layer perforated steel core.