Timmay Zoom Zoom Posted July 13, 2010 Share Posted July 13, 2010 I am looking for some parts to re-build up the bottom end of my C20XE to a good spec. Omega 86.25 pistons, I still have 2 good ones left. Upgraded Con Rods Lightned fly wheel ARP bolts Bearings Lightned and Balanced crank, I can get the one I have lightned and balaned Anything else anybody can think of that I might need for the bottom end re-build. I have another thread asking about best upgrade piston size. Thanks Tim Link to comment Share on other sites More sharing options...
peterm135 Posted July 13, 2010 Share Posted July 13, 2010 Upgrade oil pump and relief valve ? Link to comment Share on other sites More sharing options...
Timmay Zoom Zoom Posted July 13, 2010 Author Share Posted July 13, 2010 Will be running a dry sump system so no probs there. What is the relief valve? Do you mean for a turbo? am not running a turbo on this engine? Sorry for naivety, am still learning. Link to comment Share on other sites More sharing options...
peterm135 Posted July 13, 2010 Share Posted July 13, 2010 http://www.sbdev.co.uk/Info_sh....kit.htm Thats the easiest way to explain. Link to comment Share on other sites More sharing options...
Dave Eastwood (Gadgetman) - Club Chairman Posted July 13, 2010 Share Posted July 13, 2010 You don't need the relief valve with a dry sump system that's doing both the pressure and scavenge roles. If you still use the regular oil pump for pressure duty, then I'd consider the mod. Though you can achieve the same thing by turning the original steel relief valve insert down a little. Link to comment Share on other sites More sharing options...
dabar Posted July 13, 2010 Share Posted July 13, 2010 Tim, Just so you know,the engine I gave you has the sbd nylon relief valve fitted. Graham. Link to comment Share on other sites More sharing options...
Robert Posted July 15, 2010 Share Posted July 15, 2010 If it is any help I bought a set of used Omega Intruders from SteveD a few years ago for a future project which is still not started. They may be too small for you they are 86.0mm with rods and rings fitted and have 3157 stamped on them. Let me know if any interest ? Regards Robert Link to comment Share on other sites More sharing options...
Timmay Zoom Zoom Posted July 16, 2010 Author Share Posted July 16, 2010 Hi Rob, Thanks for the offer. I beleive 86 is the standard size so am looking to go a bit larger that. What CON rods do they have? Uprated steels? Still not sure what size. I have 2 86.25 that are okay, and possibly just going to source another 2, to try and keep the costs down. Can anybody give any advice/experience of re-bore oversizing pistons on a C20XE lump, pro's/con's of larger etc. I am thinking bigger is better, apart from potentially weakening the cyliders by having too thin walls. Thanks Tim Link to comment Share on other sites More sharing options...
Spannermonkey2016 Posted July 16, 2010 Share Posted July 16, 2010 Just dropped you a PM. 87mm gives 2 more possible overbores 87.5mm and 88mm. I don't think there is much performance advantage by going to 88mm unless you have big valves and want to unshroud them. I also have a SBD lightened std early type flywheel any good to you ? BTW Early or late spec engine ? Ben Link to comment Share on other sites More sharing options...
Timmay Zoom Zoom Posted July 16, 2010 Author Share Posted July 16, 2010 Hi Ben, Just sent you PM, also interested in your fly wheel. I beleive its the early engine as it has the round tooth pulleys as opposed to square ones. Link to comment Share on other sites More sharing options...
westy turbo Posted July 16, 2010 Share Posted July 16, 2010 Just go to then next oversize from what u got,88mm will give u 2.1 but thats the max. Link to comment Share on other sites More sharing options...
Timmay Zoom Zoom Posted July 16, 2010 Author Share Posted July 16, 2010 Just to advise, the engine that blew up has a hole in the side of the block. It is dead. Was gutted I have a replacement Donor block, with standard size pistons at the mo, I beleive these are 86, that I am looking to re-fresh with a re-bore for 2 reasons: 1 more Power , 2 to match the head work that I have already (QED 450 Rally cams and solid fifters with 11.5:1 CR). as with most of us, also trying to work to a tight budget so trying to work out what is best. Thanks for all the great advice, keep it comming! Link to comment Share on other sites More sharing options...
Spannermonkey2016 Posted July 16, 2010 Share Posted July 16, 2010 PM'd you back Link to comment Share on other sites More sharing options...
Robert Posted July 16, 2010 Share Posted July 16, 2010 The 86mm pistons I have are Omega Intruders and give a compression of 11.8:1 I will have to check the rods - probably standard but will let you know. Robert Link to comment Share on other sites More sharing options...
Recommended Posts