superscan811 Posted June 13, 2014 Author Report Share Posted June 13, 2014 3 steps forward 1 step back.....Block is back.Machined the pistons.Gudgeon pin plugs have been made... BUT..... Dummy assembled the rods, torqued up the rod bolts, and there was .006" clearance between the bearing surface and the crank journal.... Checked the rod journals (without the bearings) and they were .0008" tight which is good. Then I checked the bearing.FUBAR... FROM FACTORY...Have ordered another set of bearings and they should arrive mid next week. Recalculated the Compression ratio, after machining the pistons, and it looks like I'll have a 13:1 Comp engine.. Pistons lost an extra 0.7oz each after machining. Hoping to remove a bit more if it's safe to do so. Standard piston/rings/rod comes to 50.477oz (1.431kg) per assembly. My current setup weighs in at 42.258oz (1.198kg) per assembly. Nearly a 20% weight loss.. Cheers. Link to comment Share on other sites More sharing options...
superscan811 Posted June 26, 2014 Author Report Share Posted June 26, 2014 A few pics (from my phone, sorry..). Casidum coated (Diamond Like Coating) gudgen pins with the aluminium plugs to stop it moving.http://110.174.47.143/SG/Triton/12.5CR/Gudgen.jpg Top edge of the piston has been chamfered 15º (same angle as the valves). http://110.174.47.143/SG/Triton/12.5CR/Piston.jpg Lightened and balanced the pistons. Skirt has been cut down 5mm before the widest point to be safe. Pistons balanced within 0.0035ozhttp://110.174.47.143/SG/Triton/12.5CR/piston-01.jpg Over 35.27oz lighter total in the rods and pistons and while this doesn't sound like much, this weight reduction will greatly reduce the 2nd order harmonic, which is what the silent shafts used to do. In all honesty, I don't know how well the cast pistons will hold up, but this engine is just for testing more than anything else. Cheers. Link to comment Share on other sites More sharing options...
superscan811 Posted July 29, 2014 Author Report Share Posted July 29, 2014 Found a set of pistons off another type of engine, that fit quite nicely.While these are cast pistons, they have quite a few good attributes. 92mm diameter with a 35mm or 39.7mm compression height (std high comp Astron pistons are 36mm).Lighter than the standard 2.6L Astron pistons.Same gudgeon diameter as the Astrons but they are shorter, and therefore lighter.C-clipped gudgeon (perfect for the Ford rods).Drilled holes for the oil ring return rather than a large slot in the piston skirt.Friction reducing coated skirts.Cheap..(also available forged, and I'm currently looking into their pricing). STDhttp://110.174.47.143/SG/HC-ENGINE/std_piston_rod_weight.jpg New and improved http://110.174.47.143/SG/HC-ENGINE/92mm_piston_rod_weight.jpgTotal weight loss on the Piston/rod assemblies is 37.74oz,(1070grams) which is a 19% weight saving. NOT BAD..... Cheers. Link to comment Share on other sites More sharing options...
on4now4 Posted August 4, 2014 Report Share Posted August 4, 2014 (edited) Never mind my question was already answered Edited August 4, 2014 by on4now4 Link to comment Share on other sites More sharing options...
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