my slant buildup

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IDK if anyone out there is following this, (I did say early on that I was doing this largely for my records and a place to "look back on") but project creep is showing its ugly head again//// Now that I found out (and am disappointed by) that, even after a 30-thou block deck shave, my pistons still wound up that far in the hole, at TDC even after the shave.....
All along, I have been kicking around the idea of doing a draw thru turbo.... I went by the machine shop yesterday to check progress on the head... and they asked if I had a "number" to mill off the head yet. I told him I need at least 1-2 chambers CCd before I can tell him.... at this point I'm again wondering if I should.....or stay the course, and build the strongest NA motor I can that will run on pump 87?
Has anyone here, CCd a stock #447 casting combustion chamber? What do they run, unmilled? Anybody? (please don't give me links to places to figure out CR... I got a few of those from people already.... I don't yet have the number to fill in the blank for "starting combustion chamber CCs")
 
volaredon said:
IDK if anyone out there is following this, (I did say early on that I was doing this largely for my records and a place to "look back on") but project creep is showing its ugly head again//// Now that I found out (and am disappointed by) that, even after a 30-thou block deck shave, my pistons still wound up that far in the hole, at TDC even after the shave.....
All along, I have been kicking around the idea of doing a draw thru turbo.... I went by the machine shop yesterday to check progress on the head... and they asked if I had a "number" to mill off the head yet. I told him I need at least 1-2 chambers CCd before I can tell him.... at this point I'm again wondering if I should.....or stay the course, and build the strongest NA motor I can that will run on pump 87?
Has anyone here, CCd a stock #447 casting combustion chamber? What do they run, unmilled? Anybody? (please don't give me links to places to figure out CR... I got a few of those from people already.... I don't yet have the number to fill in the blank for "starting combustion chamber CCs")
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Yeah. They are usually between 53-56CCs. That's the same casting as my closed chamber head. It measured 56CCs. Being closed chamber, it was cast a little different so the chamber was a tad deeper to make it still the same volume as the open chamber heads. That's generally about where all the open chamber heads come in. The heavily milled head I have on the 225 I just put in Vixen started out at 55CCs I think it was and is not 34CCs. lol
 
My .060 over block was decked to .130" over the pistons, the head was cut .055", & using a Print-o-seal gasket it cc'd at 9.47:1 with the carbon, 9.35:1 after I cleaned everything. If You want to run that #819 OCG cam, this # is going to serve the torque below 2800 well. Or You can buy a converter that stalls at 2600+ & You're golden. The 2106R is a better torque cam, it will make a higher peak #, but less hp 3.5k & up. If You bump the CR to 9.5 You gain back 80% of the tq deficit to the 2106R, & match it at 3k. Peak would be just a tick higher as well.
Those were modeled with the same head, 8.8:1, int/exh systems.
 
Killer6 said:
My .060 over block was decked to .130" over the pistons, the head was cut .055", & using a Print-o-seal gasket it cc'd at 9.47:1 with the carbon, 9.35:1 after I cleaned everything. If You want to run that #819 OCG cam, this # is going to serve the torque below 2800 well. Or You can buy a converter that stalls at 2600+ & You're golden. The 2106R is a better torque cam, it will make a higher peak #, but less hp 3.5k & up. If You bump the CR to 9.5 You gain back 80% of the tq deficit to the 2106R, & match it at 3k. Peak would be just a tick higher as well.
Those were modeled with the same head, 8.8:1, int/exh systems.
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Geez guy.....I gotta question your numbers and math. Here's mine. Pistons in the hole at TDC .175". Block not decked. Head milled .155". Measured static dead nuts on 10:1. And yours has had .130" knocked off the block and .055" off the head and you're only at 9.47? I ain't buyin it. You're math is off somewhere. I'm running a cam with 250@ .050 duration ground on a 108 LSA with a 70 degree intake closing event and STILL have 175 PSI cranking pressure. I really think you need to recalculate. Either you've not removed as much material as you think, OR somehow you've mis calculated.....or both. You're probably closer to 12:1 if you really have that much material removed. I know mine is right from not only measuring countless times, but from the cylinder pressure and from the fight I just won with detonation.

I'm not trying to argue.....just strongly suggesting you recalculate everything. ....unless maybe you're running a dished piston.
 
Rusty... you read that wrong... He didnt say he TOOK .130" OFF the head deck, he said that he milled the deck to where the piston was .130 "in the hole" at TDC.....
2 different things (I believe)
 
volaredon said:
Rusty... you read that wrong... He didnt say he TOOK .130" OFF the head deck, he said that he milled the deck to where the piston was .130 "in the hole" at TDC.....
2 different things (I believe)
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OH! Ok, my bad then if that's what he meant.
 
volaredon said:
Rusty... you read that wrong... He didnt say he TOOK .130" OFF the head deck, he said that he milled the deck to where the piston was .130 "in the hole" at TDC.....
2 different things (I believe)
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Yeah since you threw that view out I read it again and it does appear that's what he meant.
 
got a call from machine shop yesterday, says chambers on head are at 60cc, Im surprised they came out that large. so now I could tell him how much to shave, I want to get down to ~46-48cc.... I told him from out of the air calc (hey I was driving at the time) to shave 70 thou.... I later figured out the 0.0066 per CC wanted removed, looks like maybe I should have told him closer to 80?
He did say it "checked out at" 60, which was the same as what he looked up and was listed as "typical/common".... I do know taht machine shops do have more access to such info than we do, I wish I had some of their resources.... He did say that it came out as 60cc, same as what he was able to look up, makes me wonder if he actually measured mine.... he is putting my O/S SI valves, into it.... which even if that was all that was done, that would alter the chamber volume, wouldnt it? HE also finished my porting job and is supposed to be putting seats in on the exhaust side per my request. Nothing yet has been said as to whether he had to do any guide work, I was anticipating it for sure.
 
The valves can certainly affect the volume. I used BBM1.74" exhaust valves for intakes, but they were more tulip-shaped, & the chamber face of the valve-head was very recessed. I cc'd it, & it checked at 2.4cc, the Max-Wedge 1.88" face checked at 1cc,..& was larger.
With the 1.74/1.41 setup My drool-tube head checked at 58.6cc, & ended up at 50.5cc after takin'.055" off. Oh, & after close to 30K on the unit, it lost a bit over .5cc due to carbon buildup that wouldn't brush/wipe away. Hope that is helpful.
 
Somehow that double posted, but that's OK, meant to add that I cleaned the chamber's as-cast surface up pretty good. (see pic in My "Glimpse of the past" thread)
 
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Good lord. Sounds like a nice haul. Glad yall made it ok.

Just for the record, there's no way in hades I'd ever swap a 904 when I already had a 727. Even behind a slant six. Is you crazy?
 
RustyRatRod said:
Good lord. Sounds like a nice haul. Glad yall made it ok.

Just for the record, there's no way in hades I'd ever swap a 904 when I already had a 727. Even behind a slant six. Is you crazy?
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No not at all. I ain't the one wanting to drop to a 904,never said I was, but so many are trying to talk me into it. Especially being it is still a truck, although a very light, "light truck".
 
volaredon said:
No not at all. I ain't the one wanting to drop to a 904,never said I was, but so many are trying to talk me into it. Especially being it is still a truck, although a very light, "light truck".
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Well if you do can I have the 727? lol
 
Yeah it was a crazy run getting down to GA
I hadn't realized you'd already posted a reply, I thought afterwards that my trip to GA didn't really have much to do with the motor build, so I canned the post. I'll repost trip details elsewhere.
I will say I'm disappointed, how many newer Hondas and Toyotas are running around down here, major YUCK
I'd have certainly expected to see lots more 80s and 90s cars and trucks without gaping rust holes, running around. I haven't been off of interstates yet but still. Maybe even older.
I came down in a 01 Durango with only 280k miles on it, I seem to be driving one of the oldest vehicles on the road on the way down
 
volaredon said:
yeah quite maybe if I do go ahead with the swap. Haven't completely decided yet but leaning towards leaving the 727 alone like I originally planned.
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They couldn't make me pry it outta there with a bulldozer.
 
ok, update time. Been to the machine shop a few times lately, to get a fire going as I made the mistake of saying "I wasn't in a hurry" at the beginning.....they made a "back burner" out of my slant build.... every time I go by, "Oh I was gonna call you"...... or "did the other guy call you"? No, to either version of that q.... at least every time I go in, what progress they do make between my visits, looks like they're doing a good job. Definitely cautious along the way (maybe too much so)
They were leery to shave the head 0.070" didn't realize the deck was "that thick" I told them to "just DO it".... and then I explained my predicament of the combustion chamber overhanging into the fire ring and that meant Id most likely be using an Aussie HG which is 1/2 again the thickness of "typical" aftermarket, parts store head gaskets, and I'd need "that much" to get to even "advertised" CR.... given the "piston in the hole" dimension, and the head combustion chamber "CC dimension that they came back to me with.
Yesterday, I went out there with 3-4 different HGs in hand, and showed them what I was worried about.... They are a "jack of all trades" machine shop, they do anything from SBC to Ford, Mopar, imported crap, as well as industrial and farm/ag engines. and I left one of my asbestos looking, pre-print o seal Fel Pro's behind and told them that if the OD of the chambers "shrinks" a bit/ as they do the head shave, that I could get away with a 0.050-0.055"shave ....as I could get away with about any aftermarket HG, and not have to use the (thicker) Aussie one that I showed them that one against the head, so they could really see what I meant about fire ring interference on my Fel Pro and my McCord HGs....
but if not, I'd really need the 0.070" dimension shaved off, that I originally gave them. They said "well if I know for sure that shaving that much won't bother anything, they'd do it.... "
I also talked to them about how much room I had with the cam I am running, regarding retainer to valve guide interference, and that they might have to shave the tops of the guides a bit..... I just need them to "get a move on," so I can finish assembly and get it all sealed up.
have to go thru my pile of sheet metal that I dragged back from GA...... nother story.
hope all this makes sense to "somebody" out there/
 
many years ago, I installed a 2800 on a certain slanty I had, and I really liked it.
On another slanty-build, set up for fuel-economy; I asked the machine shop to get the Scr up to 9.5, and didn't care how they got it there. I actually never checked their work. On this one I installed an A998 without a loc-up, and a lo-stall. It's a dog off the line, but does make the mpgs. I think it has 2.45s in the back. It plows snow in second gear real nice........ until it gets hung up..........
 
well FINALLY!!!
I went by the machine shop last week, 2x. In between those 2 trips they called me (see, they DO have my number!!) and he gave me a final price, all done, all in. The 2nd trip was Friday to drop off the $$... and was told "that's IT, even if they "find something else" and that it was time to "treat that head like I'm in a hurry whether I am or not". An improvement, the block and crank took 9 months, the head "only" took 3 months.... I can't get out there today, as I had a "service call" of sorts to check on for work, on the way home today... oil leak on a state cop car that the guy wanted to have towed to me.... actually in the direction I have to go, to go home anyway....(it's fixed, no tow needed) machine shop is 15 miles the "wrong" way....
am going after it tomorrow after work.
the biggest problem has been that even though I hunted and pecked out a "spec sheet" of sorts detailing what I wanted done to the head.... and they seemed to have "forgotten" about that/ though I saw it on the bench right next to my engine's head when I went in Friday..... each time I went by and asked if they had done "X" to my head yet it was like "surprise" that I'd wanted that operation done. and looking at my sheet I left with the head originally, I haven't asked for anything that wasn't on there to begin with. I asked for new guides if needed. I dunno if they needed that yet.
I dunno if they did a single angle or 3 angle VJ.
They DID finish off my start to a port/polish, and they did mag the head to be sure that neither I, or they, broke thru while porting. I dunno how much time they have in that part of the job, I know I had a day and a 1/2 into porting as far as I dared to go, before I took it in.
I told them I want 100K durability restored, this is a "truck motor" that will be sometimes used as one.
had to ask them 3x to be sure to add seats at least to the exhaust side. They initially ground new seats sized to the O/S valves (that I supplied) directly into the head casting. and then acted "surprised" that I wanted actual seats put in. which is all things that happen to a "back burner" build, things wanted get forgotten.
the other hangup was they were worried that the 0.070" I asked for the head to be shaved would be "too much" for a /6 head. Got them past that issue too.
Ive used these guys before and they do, do good work.
 
I do have a question now that I have enough stuff here to actually finish assembly...
When I get to setting the valves, Oregon Cams had a tighter spec than OE. It's still a factory /6, just a freshly rebuilt one. Thermal warming and cooling should be the same as stock, maybe a bit more "heating" with the block + head shave to bump CR. My cam is still the stock cam it left the factory with, just reground. How come the lash wouldn't still be as listed "stock"? Not looking at the cam specs right this second, but I do know they list "desired lash" the same, on both intake/exhaust. I believe the number is 12-thou. Again w/o having that sheet right in front of me. using all stock/OE original pushrods and rocker assemblies.
How/why are they spec'ing a tighter lash on the exhaust? I would think that I'd want to keep that as-factory-stock. Why wouldn't I?
 
volaredon said:
I do have a question now that I have enough stuff here to actually finish assembly...
When I get to setting the valves, Oregon Cams had a tighter spec than OE. It's still a factory /6, just a freshly rebuilt one. Thermal warming and cooling should be the same as stock, maybe a bit more "heating" with the block + head shave to bump CR. My cam is still the stock cam it left the factory with, just reground. How come the lash wouldn't still be as listed "stock"? Not looking at the cam specs right this second, but I do know they list "desired lash" the same, on both intake/exhaust. I believe the number is 12-thou. Again w/o having that sheet right in front of me. using all stock/OE original pushrods and rocker assemblies.
How/why are they spec'ing a tighter lash on the exhaust? I would think that I'd want to keep that as-factory-stock. Why wouldn't I?
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Valve lash setting specifications for mechanical cams can vary a lot depending upon the initial ramp that is ground into the cam as part of the lobe shape. I would go with what is on the cam card. Remember the valve lash that is set into the valve train is really lost valve motion. The grind that you put on the cam is probably more of a performance grind than the OE grind is. So the performance grind is all about getting the valve open sooner and keeping it open longer. A tighter lash helps with that. Bottom line is the valves in the engine will have higher opening acceleration and closing de acceleration rates compared to the stock valves. But motor oils are also much better today than they were in the 70’s so you won’t have all that sludge built up around the rocker chamber.
Question, have you worked out the valve spring height and closed and open valve spring pressures? And did you go with positive or umbrella valve seals?
 
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The modern trend is tighter lash. You don't see many 0.028/0.032" lash cams these days.
 
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