Sute Posted February 20, 2015 Author Report Share Posted February 20, 2015 Some new stuff appeared. Auxilliary belt drive pulley combined with v-belt drive.. Link to comment Share on other sites More sharing options...
Tightmopedman9 Posted February 20, 2015 Report Share Posted February 20, 2015 Crankshaft bearings are stock ones but the lower bearing will be milled to accept 270 degrees oiling to cam bearing. I'm not quite sure I understand how increasing the lubrication angle will increase oil to the cam bearings. I though that the cam bearings got their oil at the same point as the crank right off the oil pump. What size is your turbine wheel and A/R of the housing? What was your previous turbo? Link to comment Share on other sites More sharing options...
Sute Posted February 20, 2015 Author Report Share Posted February 20, 2015 The oil feed hole leading to cam bearing gets oil (while passing) from crank bearings oiling groove that is 180 degrees wide. As we now look at the phasing of the engine, the oiling shall occur only at the power stroke. When we are increasing the oiling groove to 270 degrees instead of the 180 degrees, the oil feeding hole will now pass the oil groove and furher to the rod bearing on a wider range that is 90 degrees more than stock and the oiling will not occur only on during the power stroke. The side effect will be a higher peak oil pressure on the crank bearing and more stress on crank bearing since the bearing area is reduced on load side of the bearing. Some engines do not benefit at all from this, but there are good experiences in 5 cyl engines this has worked. White block engines tend to be quite sensitive to rod bearing failures at high power levels. Link to comment Share on other sites More sharing options...
Sute Posted February 20, 2015 Author Report Share Posted February 20, 2015 Turbine is 75mm on the outlet (82mm inlet) and exhaust housing 1.15 A/R. It is under consideration wheter to go on 1.28 A/R. At 2.5 bar boost, exhaust pressure was about 0.5 - 0.7 bar lower than inlet pressure, so there was some room left. However, the engine was not really healthy, so thing might be different with the new engine. At least I hope so... Link to comment Share on other sites More sharing options...
Tightmopedman9 Posted February 20, 2015 Report Share Posted February 20, 2015 Awesome, good to know. At what power level does performing this modification usually become a consideration? Link to comment Share on other sites More sharing options...
Sute Posted February 20, 2015 Author Report Share Posted February 20, 2015 Hard to say what is the "power level" in respect of these issues since bearing clearance and used rpms plays a big role over here. I tosted bearings first time when the engine saw 650 horses. Some guys have cleared out 700 horses without bearing issues but one guy tosted at 800 horses. One Swedish guy began to have issues on his 5 cyl engine at 1000 hp level. Link to comment Share on other sites More sharing options...
VulvaS40T4 Posted February 20, 2015 Report Share Posted February 20, 2015 Engine torque seems to be the most importand factor on bearing failures. You can rev to 9500rpm on 4cyl whiteblock engine when your engine torque is maximum 750nm. After that rpm crank starts to vibrate and eats bearings if you sustain high rpm. So max 9500rpm and max 750nm seems to be okay on 4cyl. On 5cyl engines rpm limit is same but torque limit is higher. Link to comment Share on other sites More sharing options...
Midnight Caller Posted February 20, 2015 Report Share Posted February 20, 2015 Is that based on calculations or on personal experience ? Link to comment Share on other sites More sharing options...
VulvaS40T4 Posted February 20, 2015 Report Share Posted February 20, 2015 Experience on my and others engines. :) Link to comment Share on other sites More sharing options...
Midnight Caller Posted February 20, 2015 Report Share Posted February 20, 2015 Oh.. I thought you can do some resonance calculations or somenhing meaning that maybe it's not applicable to all whiteblocks (maybe aome start to vibrate at 8000rpm or lower) Link to comment Share on other sites More sharing options...
lookforjoe Posted February 21, 2015 Report Share Posted February 21, 2015 Pics of the bearing mods? It sounds like you are talking about con rod bearings, since you are referencing the crank feed / but keep saying cam bearings ( which don't exist, since the journal is part of the cylinder head)? Am I missing something? Definiely looking forward to progress pic as this all comes together Link to comment Share on other sites More sharing options...
Sute Posted February 23, 2015 Author Report Share Posted February 23, 2015 Good point Joe and sorry for the language issues! I of course ment con rod bearing. Con rod bearing is actually lubricated "through" crank bearing. Upper crank bearing has a groove and when the con rod bearing oil feed hole passes the groove it gets oil that is in that groove. The width / length of the groove is now 180 degrees and if its widen up to 270 degrees the oil feeding hole has a longer distance to travel and the oil feeding hole should lubricate the con rod bearing more efficiently i.e. gets more oil. I´ll put down some pics once this is completed. Might take some time since things are getting forward quite slowly now. Link to comment Share on other sites More sharing options...
Sute Posted March 10, 2015 Author Report Share Posted March 10, 2015 New intake valve seats and resurfaced exhaust seats in the cylinder head now and crankshaft balanced along with the rotating parts. It´s time for the assembly work. Link to comment Share on other sites More sharing options...
Ol' Dirty Noodle Posted March 10, 2015 Report Share Posted March 10, 2015 Shiny Link to comment Share on other sites More sharing options...
PoLonY Posted March 16, 2015 Report Share Posted March 16, 2015 very nice! Link to comment Share on other sites More sharing options...
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