azzy_10 Posted October 8, 2012 Report Posted October 8, 2012 i got my 3k engine and i got a 4k head I'm trying to do a head and gasget over the weekend with out taking time off work am i right to say the 4k head is a de compression on a 3k-c engine ? Quote
azzy_10 Posted October 8, 2012 Author Report Posted October 8, 2012 how much do i need to take off to get it to 3k-c 8.5-1 compression and is it still to buy 3k head gasget? Quote
shiryo Posted October 9, 2012 Report Posted October 9, 2012 3k/4k/5k headgaskets are the same so i'd presume so. Quote
snot35 Posted October 9, 2012 Report Posted October 9, 2012 Best measure it. It may have had some already taken off in a previous recondition. Quote
TRD ke70 Posted October 9, 2012 Report Posted October 9, 2012 5K isn't the same, different bore size. Quote
azzy_10 Posted October 9, 2012 Author Report Posted October 9, 2012 how much do i take off the 4k head to match the compression Quote
JDMJared Posted October 9, 2012 Report Posted October 9, 2012 You would have to cc the head, measure piston height at TDC and figure out the the thickness of your headgasket (after it is compressed) to work it out properly. Even after all that, figuring out how much to take off the head for desired CR would be a bit of a guess. If I were in your position, provided the head you are using hasn't been shaved before, I'd take about a millimetre off - it might bump you up around 9:1 but that won't be a problem. You sure as shit won't have any problems with valve clearance untill about the 4mm mark, and a little extra compression on a tired old 3k won't do no harm. Quote
azzy_10 Posted October 9, 2012 Author Report Posted October 9, 2012 well its a the work shop atm but getting it shaven flat then taking how ever much off was guna get 5thou off Quote
snot35 Posted October 9, 2012 Report Posted October 9, 2012 5thou, assuming you're talking inches, is bugger all. 1mm is roughly 40thou Quote
azzy_10 Posted October 10, 2012 Author Report Posted October 10, 2012 They took off 8 thou just to get it flat and heres a pic Needs to know how much needs to be taken off Quote
kickn5k Posted October 10, 2012 Report Posted October 10, 2012 That looks like it came up nice!! I've just thrown my digital verniers over both my spare 4k head and the corroded 3k bigport head I have lying around. The 4k head is 3.1mm or .122" taller than the 3k one. If that helps? That's only a guess as I don't know what's been taken off both. But it's a start atleast. Your still going to have to cc it though to make sure. Quote
JDMJared Posted October 10, 2012 Report Posted October 10, 2012 Judging by the spark plug holes it's had a decent ammount taken off it, I reckon that'll do you nicely. Quote
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