yoeddynz Posted March 18 Author Share Posted March 18 Well I don't think this dudes earlier 1800 has the same troubles. It just keeps bouncing back! ( I reckon a 1500 would have had its cam belt housing/pulleys smashed) This fella Matt has some cool vids inc a nice offroad trip in Idaho back country on this bike. 1 Quote Link to comment Share on other sites More sharing options...
77magnum13hundy Posted March 18 Share Posted March 18 Loving the fuel tank shenanigans proper design and thought out... not that you do anything less than awesome 2 Quote Link to comment Share on other sites More sharing options...
yoeddynz Posted March 18 Author Share Posted March 18 Thanks man. I'm glad to have sorted that bit out ok. Now scratching my head on exhaust box design. Quote Link to comment Share on other sites More sharing options...
GregT Posted March 18 Share Posted March 18 Exhaust box....An empty tube - say 4inOD 1.6mm wall. Across the back of the car. Your two sides discharging into it straight in 90deg to CL. Discharge pipes from each end. 1 1/2in OD. Length inside box to be perf tube same 1 1/2in OD. Close/blank off the inner ends of this and make them overlap with a figure 8 support in the center of the box. 90 deg bends outside the main tube for the discharge pipes to point them out the back. This will work - and not be too noisy. 4 Quote Link to comment Share on other sites More sharing options...
NickJ Posted March 18 Share Posted March 18 On 17/03/2024 at 21:09, yoeddynz said: Peak Engineering textbook and probably one of the best books ever written Shrink fit the axles is a brilliant idea, love it! 5 Quote Link to comment Share on other sites More sharing options...
GregT Posted March 18 Share Posted March 18 Sprint car and midget full width axles simply have a shrunk on flange for the final drive. It'd be easy enough to scotch key your setup if you wanted belt and braces. Quote Link to comment Share on other sites More sharing options...
yoeddynz Posted March 18 Author Share Posted March 18 I tried removing separating the test sample at local engineers yesterday. Got to 12 ton pressure and it wasn't moving and the shaft we were using to push with started bending. We called it quits before it spat out (had put a shroud around the lot but still...) I'm going back with a beefier press tool. I want to see and hear the bang No way it's gonna shift in my setup that's for sure. 3 Quote Link to comment Share on other sites More sharing options...
Adoom Posted March 19 Share Posted March 19 Can you draw a diagram showing how the K11 surge tank pump box thing works? I need to make a custom tank for my Triumph, to fit between the strut towers it has now. I'll need to figure out some kind of arrangement to prevent surge. I was thinking of putting in curved partitions so the fuel gets trapped in the 'dam' rather than going all the way to the end of the tank. I don't really have the space to make a well in the bottom. Quote Link to comment Share on other sites More sharing options...
yoeddynz Posted March 19 Author Share Posted March 19 It's really just a plastic container that fills up with fuel because not perfectly sealed around the lid. The return line goes into the bottom of the container. The pump is mounted at an angle so it's filter sock sits at the very bottom of container. Very basic and very neat. Use one of these, or a similar item (I figure a k11 pump won't be up to the task of feeding a V8 at full chat) , along with the internal baffles you suggest above and you'd be fine I think. 1 Quote Link to comment Share on other sites More sharing options...
ajg193 Posted March 20 Share Posted March 20 Shrink fits are legit. About 4 or 5 years ago I had to design an extrusion container for making magnesium rods, the container needed to be made of multiple shells of high strength (H13) steel that are shrink fitted together to get enough strength. The shrink fit was used to put something like 600 MPa of compressive stress on the inner liner, giving almost 2000 MPa of pressing capacity. I think it was something like a 0.15mm interference on about a 53 mm diameter sleeve, required temperature difference was about 250 or 300C to get it to all fit together. Was quite stressful as the liner was about 150mm long and had a nitrided surface so any lathe tooling would just bounce right off if it grabbed and needed to be redone. 4 1 Quote Link to comment Share on other sites More sharing options...
yoeddynz Posted March 20 Author Share Posted March 20 I was reading somewhere that some large camshafts are constructed with the lobes shrunk fit in place. I'll try find it. Figure it cuts down on material and machining costs a lot when dealing with big items. 1 Quote Link to comment Share on other sites More sharing options...
ajg193 Posted March 20 Share Posted March 20 Briggs and Stratton camshafts have nylon lobes that are injection molded directly onto the shaft and they never seem to fail Quote Link to comment Share on other sites More sharing options...
yoeddynz Posted March 21 Author Share Posted March 21 Molded onto a steel shaft? Quote Link to comment Share on other sites More sharing options...
tortron Posted March 21 Share Posted March 21 6 minutes ago, yoeddynz said: Molded onto a steel shaft? The black ones look better I think the key is low rpm, and Bic pen valve springs 3 4 Quote Link to comment Share on other sites More sharing options...
thegreatestben Posted March 21 Share Posted March 21 I remember pulling apart the motor that was in the ride on mower I bought off @Nominal a number of years ago and thought the plastic components were surprising and you can’t help but think that can’t be good, but in saying that the reason that motor had given itself an upper cut was due to a metal (cheese) part giving way. I think if any of the plastic gave up it wouldn’t run but unlikely it would have ventilated the case either. Was the little pivot arm 757 in this diagram that let go. 3 Quote Link to comment Share on other sites More sharing options...
ajg193 Posted March 22 Share Posted March 22 8 hours ago, tortron said: The black ones look better I think the key is low rpm, and Bic pen valve springs My steam converted briggs still had the plastic gear and I beefed up the valve seat pressure to over 100 PSI, surprising what those parts can handle 1 Quote Link to comment Share on other sites More sharing options...
VitesseEFI Posted March 23 Share Posted March 23 Quite a lot of modern Euro stuff has camshafts lobes that are either shrunk fit or have a hollow shaft hydro-formed under them. The lobes occasionally move - bad things happen. Destruction. General mayhem. Shrapnel…. 1 Quote Link to comment Share on other sites More sharing options...
igor Posted March 23 Share Posted March 23 1 hour ago, VitesseEFI said: Destruction. General mayhem. Shrapnel… Designed in failure to make the consumer buy more new cars. 2 Quote Link to comment Share on other sites More sharing options...
GregT Posted March 24 Share Posted March 24 5 hours ago, VitesseEFI said: Quite a lot of modern Euro stuff has camshafts lobes that are either shrunk fit or have a hollow shaft hydro-formed under them. The lobes occasionally move - bad things happen. Destruction. General mayhem. Shrapnel…. Some time back, talking to my local camshaft regrinder - who has a contract with Cosworth USA for "import" cams - I was told that 90% of the cast iron blanks come from Turkey. I'm wondering if the fairly recent quakes there have affected the supply to the point where manufacturers are now using alternatives to CI. Quote Link to comment Share on other sites More sharing options...
VitesseEFI Posted March 24 Share Posted March 24 15 hours ago, GregT said: I was told that 90% of the cast iron blanks come from Turkey Dunno about quakes. I do know that QC can be an issue. Previous company went through a fairly short phase of source CI pump casing parts from a Turkish foundry. Sizeable voids stuffed with car body filler and painted over don’t hold pressure very long! Quote Link to comment Share on other sites More sharing options...
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