oldeskewltoy Posted April 8, 2015 Report Posted April 8, 2015 Got this via FedEx yesterday.... I've gotten heads in all kinds of containers/packaging. But this one is unique, and lead to the title..... :) It has very interesting latches.... I wish all clients would be able to do this....... Safe and secure with plenty of protection around it the head is clean, and it comes with all the hardware.... ..... along with a set of Pon cams!!!! More to come....... :yes: Quote
snot35 Posted April 9, 2015 Report Posted April 9, 2015 Ah, Poncams! 264? I'm interested to hear what power this ends up with. Quote
oldeskewltoy Posted April 9, 2015 Author Report Posted April 9, 2015 Ah, Poncams! 264? I'm interested to hear what power this ends up with. A similar build planted around 150whp, or about 170 @ the crank hmmm...military owner by any chance?...we use those cases for equipment/parts That's a flight case' date=' often used by musicians and such. The latches are very similar to those used in Military cases (non Peli type) as they have a high latch strength and low profile :) [/quote'] Now I (we all) know about this kind of case/latch :thumbsup: While OST-031 is being cleaned and pressure checked, it gives me a few days to work on OST-030... Besides the Poncams, my client is using a piston with a 3.2cc dome. He has to check, but believes he has .005" of positive deck - piston slightly ABOVE the blocks surface. He wants to run a squish of .040". What chamber volume does he need for a 11.3 to 1 compression ratio? My clients said his head had been already run through the mill once... .008" Seems pretty close to me.... btw... look at the "round" exhaust port... :wtf: 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, I'll be checking these journals for similar issues..... Work begins on the bowls and seats of chamber #1 More to come.... :D 1 Quote
oldeskewltoy Posted April 10, 2015 Author Report Posted April 10, 2015 What do you do about bad cam journals and caps? not ignoring you... not quite ready yet to show that part of the process :) Is this a CA customer? 11.3 on 91 octane' date=' better have clean chambers, and management dialed in nicely, my recommendation from experience... I would even worry that improved breathing/VE would skew things even more toward a little less CR. If this is 93 octane, probably it's fine, but potentially close to incipient detonation.[/quote'] Other side of the country..... Part of the issue is opening the chamber to accommodate the piston. With the clients deck, and the piston volume, the chambers may need to be "opened". Most pistons can be milled a few ten thousandths, which could drop the piston volume under 3cc example of piston milling The piston I designed could be milled .030" and drop the dome volume from 2.5cc to about 1.8cc. 1 Quote
oldeskewltoy Posted April 10, 2015 Author Report Posted April 10, 2015 #1 is almost finished... Here is #1 exhaust bowls/port in transition And a closer view of the short radius, and the port in the background More to come....... :D 1 Quote
oldeskewltoy Posted April 13, 2015 Author Report Posted April 13, 2015 2 down.... 2 to go..... Chambers..... exhaust ports..... More to come....... :D 1 Quote
oldeskewltoy Posted April 14, 2015 Author Report Posted April 14, 2015 further progress... 3 down 1 to go.... this time the intake view - first short radii... followed by the view down the ports The exhaust... And the chambers... 3 panel this time so you can see the progression More to come..... :D 1 Quote
oldeskewltoy Posted April 16, 2015 Author Report Posted April 16, 2015 4 down...... Next stop valve job and resurface... and then we set chamber volume.... More to come....... :D 1 Quote
altezzaclub Posted April 16, 2015 Report Posted April 16, 2015 ooohh shiny! You do bring them up nicely! Isn't there more to take out of the exhaust port to match the gasket? or doesn't that add enough flow to worry about? Quote
oldeskewltoy Posted April 16, 2015 Author Report Posted April 16, 2015 (edited) ooohh shiny! You do bring them up nicely! Isn't there more to take out of the exhaust port to match the gasket? or doesn't that add enough flow to worry about? Shiney is a bit mis-leading... yes it is shiny... but much of what you see is the lighting I used. The last frame in the gif showing the intake port above actually shows the deshrouded chamber, as well as the ports... the chamber is suppose to be shiney.... as is the exhaust ports. The intake ports are brought to a consistent finish with 125 grit Matching the gasket doesn't "fix" the problem inside the 4AG head, it just tend to mask it. So what is the problem in the exhaust ports of a 4AG head? The taper inside is all wrong..... Here is what I do inside.... Notice the inside wall has been significantly changed, while the outside hasn't.... How about a positive view of my work.... After is on the right..... A straighter path lowers pumping losses.... Problem with gasket matching... if the engines installer doesn't hang the exhaust correctly, the top of the matched exhaust port can be interfered with because the gasket tends to have about a millimeter of slop on the studs... so I port the roof so that when the gasket is hanging on the studs, the roof is less than a millimeter from the gaskets edge. As to "opening" the floor of the port exhaust... I've only done it once, to an O/S valve head I made a few years ago... As to improvements while keeping the outlet nominally @ the stock opening Edited April 16, 2015 by oldeskewltoy 1 Quote
oldeskewltoy Posted April 16, 2015 Author Report Posted April 16, 2015 Back to OST-030..... Besides the Poncams' date=' my client is using a piston with a 3.2cc dome. He has to check, but believes he has .005" of positive deck - piston slightly ABOVE the blocks surface. He wants to run a squish of .040". What chamber volume does he need for a 11.3 to 1 compression ratio? My clients said his head had been already run through the mill once... .008" [/quote'] Here is what is now known.... 82mm bore or 3.229" 77mm stroke or 3.031 .012" piston sticks out of the bore .052" Cometic gasket 3.2cc piston dome So I ask again what chamber volume does this build need to have a static CR of 11.3 to 1??? Now how do I achieve that target volume on a head already cut .008", and will be cut an additional .002"???? Quote
altezzaclub Posted April 16, 2015 Report Posted April 16, 2015 if the engines installer doesn't hang the exhaust correctly, 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. Quote
altezzaclub Posted April 16, 2015 Report Posted April 16, 2015 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! Quote
bruce Posted April 17, 2015 Report Posted April 17, 2015 What did you use to create the port moulds? Something like silicone RTV? Tricky to pull out? Quote
Mechanical Sympathy Posted April 17, 2015 Report Posted April 17, 2015 These threads make for great reading. Don't ever change! I'd love to see what you could squeeze out of a 2TG but I don't expect you'd come across many of them in the U.S. Quote
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