rebuilder86 Posted February 9, 2018 Report Share Posted February 9, 2018 (edited) Giday all. On my way out of cebu, back to perth, I went to the middle of hell, the streets of old cebu city, stopped in at all the stores that sell surplus engine parts and found the worlds holy grail of toyota k engine parts. ANGELS SING!! So, when i head back, i will have myself a correct 4K-U cylinder head, with the lugs under 1 and for indicating its for dished 4K-U pistons. FYI, this head was stamped number "1" so our wiki page is incorect. The combustion chamber section of the head is notably smaller in volume than my non twin squish head, designed for flat tops. In photos you cannot really tell, but when its in your hand, u can visually see with depth perception fro your 2 eyes, that the chamber is much smaller. My question to you all. How much of a difference do we all predict this will give me with economy and power? That is; going from the incorrect low compression setup, to the correct compression setup. I have no way of measuring power output, so i will be basing my findings on economy alone. Just wondering if anyone has any experience with this or has any idea how much improvement i might expect to see.. I believe i will have to do something with the push-rods as Banjo has warned me the thickness of this head would be different to that of a std flat top 4k head. Also the man at the suprlus store, in broken english, mentioned this head being different height to another (some other head, not specific). Our wiki page shows this information for push rods: 4K - 186mm 4K(with lugs) - 180mm 5K(solid lifter, D-Dish piston) - 180mm I didnt measure mine because i didnt think about this, but i think this data shows that the 4k with lugs (for dish pistons) would have a shallower head height... is this correct? If so I'm thinking ill be able to just cut and weld my pushrods down from 186 to 180 mm. Every second man is a welder with a welding shop where i live, so that wont be a problem. Further info for others. The Toyota genuine model number for a 4K-E head is exactly the same as that for a 5k head. this means heads will line up bolt together wiht differnet size blocks, and are relatively interchangeable with some other adjustments necessary. They share the same head, and compression ratio is just slightly different due to the bore size. the 5 k (d dish) has higher compression ratio (than 4KU D dish) purely because its bore size is larger.er Edited February 9, 2018 by rebuilder86 Quote Link to comment Share on other sites More sharing options...
Banjo Posted February 9, 2018 Report Share Posted February 9, 2018 (edited) That is incredible Jeremy ! I figure that guy is standing at the door looking in, because he can't get any further into the building. The sign next to him says NO PARKING, I believe; so I guess, that if you park too long outside, they just dissemble your car, or truck, & take the bits inside. So what happens, if you say you want that gearbox I've arrowed ? I suppose we'll never know, as it is a little bit big & "heavy duty" for a Rolla conversion. (come back in a month ?) Amazing ! I guess you are asking how much extra HP you are going to achieve, with the increased CR, by fitting the correct head. You will have to measure & calculate cylinder & head combustion areas accurately, before & after, to work that out. I think its a case of suck it & see, but it will be an improvement over the very low CR you currently have. Enjoy your trip back to Perth ! Have you got a "shopping list" of things you need to take back ? P.S. For heavens sake, do not cut & weld push rods ! A recipe for a disasaster. Cheers Banjo Edited February 9, 2018 by Banjo Quote Link to comment Share on other sites More sharing options...
parrot Posted February 9, 2018 Report Share Posted February 9, 2018 What a classic. i reckon that bloke is paid to stand there and his left foot stops the whole lot from collapsing outward. Quote Link to comment Share on other sites More sharing options...
rebuilder86 Posted February 9, 2018 Author Report Share Posted February 9, 2018 hahahaha. i think they are a little bit foolish for stacking al those usefull parts liek that, but they simply have no room. and the truth is, if you walked up to the manager in the back office with a sample part, he would remember what is under that pile and tel u if he has it or not. All the back is organized, but the marketing in this country is different. they liek to have as much stock visible from the street as possible, and it works; i wanted to walk inside to explore. i was rewarded by what i saw. What exactly are pushrods made of, it can't just be carbon steel, i left mine on the drivers seat while i was doing the head rebuild and there was no rust on them after a week in the humidity. I really trust the welders there. they are quite amazing. i recon they would sleave it and boodgie weld it. Maybe not goood enough to weld pushrods but i recon if one snapped, the valve would just close... maybe not? Quote Link to comment Share on other sites More sharing options...
rebuilder86 Posted February 10, 2018 Author Report Share Posted February 10, 2018 ok so i think what i will do is. Return to cebu with my turbocharger which i am testing for an Australian turbo manufacturer. (don't ask, long story) I will install it with the existing setup, engine in poor state with poor compression ratio. The poor ratio will make the turbo able to run relitively reasonable bost without much danger of detonation. Then, once all testing is done, ill take the engine apart, measure the combustion chamber volume in the head and pistons, and work out the ratio. then do the same with the new head and work out the new ratio. Quote Link to comment Share on other sites More sharing options...
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