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i have a set of brand new rb30et acl race fordged pistons complete kit with pins and rings and a race series head gasket 1mm steel for sale 1000ono pistons retail for $1100 head gasket $240 or so all brand new in og box and packaging.

ps i think pistons are 20thou over size check in the morning

Edited by ELMOHASA33

hi these are the specs i have if you need any more info contact david bird at mahle i did work out the comp ratio once for a twin cam head using these figures i think it was 8.5:1 but you should be able to work it out with the specs below

COMPRESSION HEIGHT: 32.100 mm

BOWL(-)/CROWN HEIGHT: -2.50 mm

BOWL/DOME VOLUME(-): 12.00cc

RING SET SERIES : M1686

PISTON LENGTH : 64.000 mm

PIN DIAMETER : 21.000 mm

David Bird

Applications Engineer

MAHLE Engine Components Australia Pty Ltd

2-8 Oxford Road, Laverton North, 3026. Victoria. Australia.

Phone: +61 (0) 3 8368 1825, Fax: +61 (0) 3 9931 1531

email: [email protected], Internet: http://www.mahle.com

this is the formula for working out compression ratio

one cylinder swept volume + deck cc + head cc

deck cc + head cc

Example: 545 + 3.378 + 48 = 596.378

3.378 + 48 = 51.378 = 11.6:1

In this example, 11.6:1

the deck cc =12ccs

neo head has 50 to 54 head ccs

using this formula and these pistons bore would be 87 stroke 85

gives a 3031 ccs with a swept volume of 505.29887 per cylinder

so 505.29887 + 12 + 50 =567.29887

12+50=62

567.29887 %

62 = 9.1:1 this is the unadjusted compression ratio "dosnt include head gasket

any change in any of these figers will change comp ratio so ceck what you have

Edited by ELMOHASA33

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