rj Posted October 30, 2006 Share Posted October 30, 2006 Peter, One thing I'd check is whether you've got the later or the earlier oil pump. The early has a narrower rotor, the later rotor is 11.5mm thick. QED do a steel rotor, which I'll use in my engine. /regin Link to comment Share on other sites More sharing options...
Jason Plato Posted October 30, 2006 Share Posted October 30, 2006 QED do a steel rotor, which I'll use in my engine. Caution Regin - I have rejected 2 steel oil pump rotors from QED as they were machined in correctly and would have caused the pump to seize if used . I stuck with the Rover one and replaced each year . Dave here is C7 TOP South Wales AO Link to comment Share on other sites More sharing options...
Jason Plato Posted October 30, 2006 Share Posted October 30, 2006 If you are running slicks and doing a lot of trackwork then the stock crank may be vulnerable across the rear main bearing. Always my concern when using a std crank - even when using tyres like 48R's on standing sprint starts covering the first 64 feet at 1g . Or kerb hoping slightly on trackdays and sending shocks through the transmission. My other big concern has also been the center line bore of the bores and ovality - especially when not using original Rover liners or other interference fit liner systems. I would certainly check this under compression with a troque plate if I were to use another interference fit liner block again. I have also rejected 2 blocks for this problem. If budget wasnt an issue than I would certainly use the strengthened super 1600 block and fit PTP or perfect bore liners and go for a 2L engine or 1943cc or whatever the capacity works out to be for the rover touring car engine. here is C7 TOP South Wales AO Link to comment Share on other sites More sharing options...
Leadership Team SLR No.77 Posted October 30, 2006 Leadership Team Share Posted October 30, 2006 Keep it coming guys, great thread Stu. Link to comment Share on other sites More sharing options...
rj Posted October 30, 2006 Share Posted October 30, 2006 Thanks Dave! Maybe one should have his own made up then... Link to comment Share on other sites More sharing options...
Peter T Posted October 30, 2006 Author Share Posted October 30, 2006 What block is the srengthened version Dave? Certainly Perfect bore liners would be much better to use than the standard Rover items? Why do the liner go oval when bored? Is it that the machining work has to be done with a torque plate? R500 Mango Madness Link to comment Share on other sites More sharing options...
oilyhands Posted October 30, 2006 Share Posted October 30, 2006 The machining work is done with a torque plate and at the engines operating temperature. I have not had any issues with Scholar blocks but there is a lot of flak flying around the internet at the moment. I routinely measure the ones I use with a torque plate attached and have never seen and OOR values that have caused concern. Dave Link to comment Share on other sites More sharing options...
Rob Walker Posted October 30, 2006 Share Posted October 30, 2006 Peter, Even with the use of a torque plate and the block heated to operating temperature it still difficult to replicate the exact forces that are placed on the liners by the actual head, as the head warps when correctly torqued down. In order to understand the problems lets look at the head gasket and there are a few different types of these, basically there are two restrictor plates one at each end of the gasket .050" thick and the fire rings are .070" thick as the head is pulled down to its full torque the fire rings compress until the restrictor plates contact the block and head gasket faces. So to put it crudely the head is bent over the protruding liners. If you now check the cam ladder face it will have distorted .001-.002" this is why it is better to shim the cams with the head in place. I digress, This distortion is not confined to the head we know this because one cannot easly turn the crank without some head bolt tension. This is because the journals have been line reamed in manufacture whilst the block was under the compressive loading of the head bolts. What I am trying to say is that the whole lot distorts when the head bolts are torqued up and the torque plate does not replicated the head exactly. As the loading applied to liners when they are machined in situ is not exactly the same it is reasonable to assume that they will be a different shape when the head is fitted. Rob Link to comment Share on other sites More sharing options...
Peter T Posted October 30, 2006 Author Share Posted October 30, 2006 Crikey, it sounds very difficault to actually measure anything correctly How do Rover check clearences then if you cannot actually check them yourself ?/ Why has something so simple been made so hard? How can you check if the crank binds in the block? Why was it designed to flex that you cannot accurately measure? R500 Mango Madness Link to comment Share on other sites More sharing options...
oilyhands Posted October 30, 2006 Share Posted October 30, 2006 The differences between clamping with a head and with a torque plate should be minor Rob. An alternative is to use a head as a torque plate and use and excavated oil rail that will allow the bore to be measured from the bottom. I always check crank rotation after assembly with a torque plate and standard gasket, you only need around 30-40NM applied to straighten the main bearing tunnels. The distortion you get with the stock loose liners when the head is tightened down can be major. Selection of the correct gasket and setting correct liner heights can help. Dave Link to comment Share on other sites More sharing options...
Rob Walker Posted October 30, 2006 Share Posted October 30, 2006 Peter, Sorry I can only answer part of your posting. How acn you check that your crank does not bind inthe block? Its is straightforward to measure the crank OD journal faces with a micrometer, next you select the correct bearings as per the lettering on the block and crank. Asemble the engine and its should be possible to rotate the engine with 33lb ft torque applied at the crank pulley bolt. obviously there could be other reasons why the engine may be harder to turn than the prescribed 33lb ft but it does indicate that further investigation is required. Rob Link to comment Share on other sites More sharing options...
Rob Walker Posted October 30, 2006 Share Posted October 30, 2006 Dave, Good tip I had never thought of checking the crank with the torque plate on. This would certainly highlight any problems with the crank , block and bearings without the influence of the valve gear etc. Rob Link to comment Share on other sites More sharing options...
Peter T Posted October 30, 2006 Author Share Posted October 30, 2006 So Dave the answer is to fit better fitting liners that can alliviate the distortion problems that arise through torqueing of the head? Rob, just measuring the crank journals is clearly 'that is stated ' of no use because the whole unit flexes before the head is torqued down and the unit becomes as one. What process as an engine builder of these units would you suspect if 30-40 Nm would not turn the engine? Does this mean that some do go out with a slight binding? Also this procedure is very time consuming and expensive to the person having an engine built. Perhaps the horror stories are from non reputable builders who have ignored these stringent rules who have given the ' K ' the reliability issues that proceeds it? R500 Mango Madness Link to comment Share on other sites More sharing options...
martinwhitcher Posted October 30, 2006 Share Posted October 30, 2006 excellent thread guys Martin MW 51 CAT Superlight No.171 now known as:Superlight DVA 207 Link to comment Share on other sites More sharing options...
Peter T Posted October 30, 2006 Author Share Posted October 30, 2006 Feel free to inject any questions. R500 Mango Madness Link to comment Share on other sites More sharing options...
martinwhitcher Posted October 30, 2006 Share Posted October 30, 2006 Peter, What are you planning to do to your engine? as you may well know I am/DVA is building me a *reliable* 240+BHP. be interested to know what spec/ideas you have? Martin MW 51 CAT Superlight No.171 now known as:Superlight DVA 207 Edited by - Martin Whitcher on 30 Oct 2006 21:19:55 Link to comment Share on other sites More sharing options...
oilyhands Posted October 30, 2006 Share Posted October 30, 2006 The block and ladder require a *lot* of preparation before the bearings are layed. It is also important to thoroughly inspect the bearing shells themselves to ensure that there are no burrs on the ends of the shells that could affect the assembled alignment. These are mass produced items and can often suffer due to production machinery nearing the end of a calibration. The crank too requires proper cleaning and preparation. quite often the crank drillings do no exit to the bearing at the correct angle and the ends of the holes require work to encourage the oil out into the bearing as easily as possible, similarly with the feeds from the mains where the crank is cross drilled. Great care has to be taken here to ensure the journals are not marked and that the oilways are properly cleaned. If the crank is difficult to turn with the torque plate fitted then either the bearing clearance is wrong, the crank is bent or the bearing tunnels are disrupted in some way. This has only happened once that I can remember and the resistance to rotation was very small, after removing and mic'ing the crank one of the bearings was larger than the stamped number indicated, a thinner shell commensurate with the correct dimension did the trick. Oily Link to comment Share on other sites More sharing options...
Peter T Posted October 30, 2006 Author Share Posted October 30, 2006 Thanks for the clarification on the shells. Many questions i know but if i don't ask then i don't learn Again my quest for better engineering quality components is ... why can't i use a better bearing that has far superior tolerances than the Rover parts offered? Surely this simple solution can lessen the risk of malfitting bearings? Do cleveland Vandervell bearings make the standard rover supplied units? Is this a weird way to find what fits works method? So far on my enlightenment of this new engine to me is throwing up complicated issues with widely accepted parts that possibly render the ' K ' unreliable. R500 Mango Madness Link to comment Share on other sites More sharing options...
oilyhands Posted October 30, 2006 Share Posted October 30, 2006 Since the crank is graded for size and the bearing ladder/block/rods are also graded for size it is necessary to select bearings of the required thickness in order to maintain correct bearing clearances. Only the Rover bearings come in the required selection of thicknesses to do this, after market bearings such as VP2, Cleevite and AE come in just one size, therefore the bearing clearances will be hit and miss at best unless the size grades on block/crank and rods all happen to be perfect for the intermediate size. The later TF160 type bearing is quite tough and seems adequate for over 280BHP so there seems little point in using anything else. The 1600 bearings in the older AS15 material are notorious for breaking up and I have seen two engines suffer failures due to bearing fatigue. Even on standard engines these bearings are known to have suffered collapses. Inpecting the bearings for small manufacturing anomalies is necessary *whatever* the source, be they Vandervell, Cleevite , AE or Rover, I have seen sufficient quantity of all to know that problems can occur on all. Oily Link to comment Share on other sites More sharing options...
Peter T Posted October 30, 2006 Author Share Posted October 30, 2006 Would it not be easier then to line bore under tension the ladder block? This way all the bearings would be the same size and rebuilding would be far easier would it not? R500 Mango Madness Link to comment Share on other sites More sharing options...
oilyhands Posted October 30, 2006 Share Posted October 30, 2006 That would require remachining of all the flat surfaces as well, since the crank bearing tunnels are graded at the factory and the cranks pins are also graded, all that is necessary is to measure the tunnels under the influence of a torque plate and mic the crankpins. If these are as expected then the normal selection process can take place. The beatings would only be all the same size if all the journals were also the same size and intermediate size at that. Oily Link to comment Share on other sites More sharing options...
Rob Walker Posted October 31, 2006 Share Posted October 31, 2006 Dave, It may surprise you that two of the UK `s well known engine builders simply fit the Blue Blue medium grade main bearing shells and carry out the simple torque to turn the crank test. It is a bit difficult to do anything with vandervell VP2 big end bearings as the surface is so easily damaged and they are not size graded. Rob Link to comment Share on other sites More sharing options...
Rob Walker Posted October 31, 2006 Share Posted October 31, 2006 I understood that the main bearing tunnel was line bored and reamed whilst under head bolt torque by the manufacturer ? I aways assumed this to be so as the whole lot only goes out of line when the torque is removed and the slight differences in sizes due to the machining process? Link to comment Share on other sites More sharing options...
Steve Cragg Posted October 31, 2006 Share Posted October 31, 2006 This is a great thread Someone should post a link to this thread on Exige.com to demonstrate how people can have an adult discussion about engine building without getting into a slanging match. Steve Superlight #63 Link to comment Share on other sites More sharing options...
Leadership Team SLR No.77 Posted October 31, 2006 Leadership Team Share Posted October 31, 2006 It may surprise you that two of the UK `s well known engine builders simply fit the Blue Blue medium grade main bearing shells and carry out the simple torque to turn the crank testWhy would any engine builder do this? Having watched Oily rebuilding my bottom end ( 😳) It's not rocket science - just care and attention to detail that any quality engine buider should do AFAIK the torque test will only really check for a tight shell - they can be under size also! Stu. Link to comment Share on other sites More sharing options...
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