oldeskewltoy Posted April 17, 2015 Author Report Share Posted April 17, 2015 What did you use to create the port moulds? Something like silicone RTV? Tricky to pull out? Fair enough. I pin the extractors to the head so they go on exactly each time, and I glue the gasket onto the head in a couple of spots to hold it in place. Many of my clients don't fully understand the effects... in many cases the detail I show in the headwork goes a long way to educate them. Remember MANY 4AG powered cars are in the hands of low budget, or first time owners.... Without checking it.. stroke volume is 3.14x41x41x77=369.5 piston sticks up 3.14x41.41.0.3=1.6 gasket is 3.14x41x41x1.3=6.86 Let X be the head volume. So the BDC volume is 369.5+6.86+X-1.6-3.2 which is 371.56 + X The TDC volume is X +6.86 -1.6-3.2 which is X + 2.06 For an 11.3 to one CR BDC volume = 11.3(TDC volume) 371.56 + X = 11.3(X + 2.06) 371.56 + X = 11.3X + 23.28 371.56-23.28 = 11.3X - X 348.28 = 10.3X so X = 34.83 ..and can I have 25minutes of my life back please! oh' date=' and account for the gasket too. so chamber volume will need to be so swept volume is 406638.3mm^3 so your desired theoretical chamber volume will be 35985.7mm^3, just add or subtract the various volumes from this, no? is the "dome" of the piston convex or concave?[/quote'] As to the chamber volume I'll need... I find to save time, and poor calculating skills on my part - I use one of the online compression calculators..... https://www.rbracing...staticcalc.html or http://www.csgnetwor...m/compcalc.html in both cases we come up with about 37cc (37.3 in the RB racing calculator) Quote Link to comment Share on other sites More sharing options...
oldeskewltoy Posted May 7, 2015 Author Report Share Posted May 7, 2015 So with OST-031 now @ the machine shop getting its valve job and surfacing we delve back into OST-030 I've gotten the head back from the machine shop, they have provided a minimum resurfacing .003", to add to the previous clients report of a .008" resurfacing, the current surface is not quite @ .011, closer to .0102". This head is now 115.74mm thick, having had a total of .26mm removed. Typically with a 10 thou cut you can expect chamber volumes to drop to about 35cc, the deshouding adds about .4cc, to gain volume I had the valve seats machined an extra .003" to gain 1cc in chamber volume, this lowers the valve on the seat allowing for a bit more volume in the chamber. The valve tips were cat an equal amount so use of more common shims sizes is retained. So right now the chambers sit @ 36.4cc (1/10cc tolerance) All the cam journals look pretty much the same as this... Since MR2tailbreaker noticed a "small" problem in his cam and journal clearances using the Poncams' date=' I'll be checking these journals for similar issues..... [/quote'] The FSM(BGB) states the cam to journal clearance to be .035mm to .072mm, with nothing greater then .1mm Using the Plastigage PL-X - The PL-X range is a bit on the tight side for measuring the whole range of the cam to journal - a bit too small for perfect accuracy, but in this case it works adequately. This is one of the measurements, you can see it is quite a bit narrower then .045mm which is middle tight of the span in the FSM. By carefully surfacing the cam cap "feet" we can get this dimesion closer to the center of the specification Here is a 2nd journal going from a bit loose.... to middle of the spec Of course the worst one I didn't get a photo of, that was #5 on the intake side... farthest from the oil supply, it was so loose that most of the Plastigage thread was intact when checked, and it too was brought into spec. Now that the cam journals are all within tolerance, assembly can begin..... More to come..... :D 1 Quote Link to comment Share on other sites More sharing options...
rian Posted May 8, 2015 Report Share Posted May 8, 2015 :y: I'm loving how technical/well documented this thread is. Quote Link to comment Share on other sites More sharing options...
oldeskewltoy Posted May 8, 2015 Author Report Share Posted May 8, 2015 :y: I'm loving how technical/well documented this thread is. ;) thanks... Showing off her angles.... Now that the cam journals are all within tolerance' date=' assembly can begin..... [/quote'] The head and hardware are all laid out, #1 cylinder already has the valves in.... Now half assembled... sometimes during assembly you see something that you just don't like.... tossed the retainer on the left for the one on the right. There was no other damage, I just didn't like that kind of a flaw. Fully assembled... now whats left is setting the valve clearances, and getting it back to my client. More to come..... :D 1 Quote Link to comment Share on other sites More sharing options...
oldeskewltoy Posted May 12, 2015 Author Report Share Posted May 12, 2015 Valves @ full lift... Exhaust.... Intake... Fully assembled... now whats left is setting the valve clearances' date=' and getting it back to my client. [/quote'] Its packaged back in its case.... with the latch zip tied down... I heated the end of my punch a bit so I could get it to impress into the ziptie. All that is left on this is shipping back to my client.... Quote Link to comment Share on other sites More sharing options...
altezzaclub Posted May 12, 2015 Report Share Posted May 12, 2015 I heated the end of my punch a bit so I could get it to impress into the ziptie. Haha! cute! Quote Link to comment Share on other sites More sharing options...
oldeskewltoy Posted May 24, 2015 Author Report Share Posted May 24, 2015 All that is left on this is shipping back to my client.... Why I insist on insuring the finished product for its shipment back to it's owner...... I've been told the head itself did not sustain any damage... but this shows significant intrusion.... so when I say the insurance adds $20' date=' or $30 to the return shipping cost... its just to [u']COVER YOUR ASSets.[/u] Quote Link to comment Share on other sites More sharing options...
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