Guest iskone Posted March 29, 2005 Share Posted March 29, 2005 It looks my head has been shaved 7 thou. Know where I coould look around to get the camber volume. I don't want to pay for cc'ing but I may look into doing it myself. Who's tried it? Isk Quote Link to comment Share on other sites More sharing options...
JMortensen Posted March 29, 2005 Share Posted March 29, 2005 .007 is pretty minimal. That's not going to significantly effect compression ratio or volume IMO. I cc'd my chambers on on my E31. It's pretty easy. I used a piece of lucite that I got from Home Depot, and smeared a super thin layer of white grease around the chamber then stuck the lucite on top. I had drilled a bunch of holes in the lucite and filled the chamber with water that I poured from a graduated cylinder. I got the graduated cylinder from a hobby store. It was marked to the .5cc, but there was enough space between the marks that my chambers are probably within .2 or .3 cc. I did three things wrong. First I kept putting one of the two valve springs on the cylinder I was working on, so there was a lot of compressing springs going on. Second, I also torqued down the spark plug so that it was water tight. The third thing was I used water. Apparently you can use a little white grease on the valve seat and the spark plug threads so that you don't have to mess with the valve springs and the spark plug, and instead of using water if you use alcohol it's apparently much easier to avoid bubbles under your lucite, which means that I probably wouldn't have needed so many holes drilled into the lucite. Quote Link to comment Share on other sites More sharing options...
Guest iskone Posted March 29, 2005 Share Posted March 29, 2005 I don't know what I was thinking when I posted. Oliver a t Z Specialties told me 7 thou but he must have meant something else. He keeps telling me the head has been shaved a lot. He told me the combustion volume looks at least as small as an E31 if not smaller. Isk Quote Link to comment Share on other sites More sharing options...
katman Posted March 30, 2005 Share Posted March 30, 2005 A lab quality burette (which is what you should be using, check Fisher Scientific) will cost more than the shop should charge you for measuring the chamber volume on 6 chambers. Good grief. The volumes "look" smaller than an E31? Do they know some E88's have E31 chambers? Have them cc it so there's no doubt. Ballpark is every .010 you shave reduces the volume by about 1cc on the '72 version of the E88. The head would have been 4.248 to 4.253 thick stock. Quote Link to comment Share on other sites More sharing options...
Guest iskone Posted March 30, 2005 Share Posted March 30, 2005 A lab quality burette (which is what you should be using' date=' check Fisher Scientific) will cost more than the shop should charge you for measuring the chamber volume on 6 chambers. Good grief. The volumes "look" smaller than an E31? Do they know some E88's have E31 chambers? Have them cc it so there's no doubt. Ballpark is every .010 you shave reduces the volume by about 1cc on the '72 version of the E88. The head would have been 4.248 to 4.253 thick stock.[/quote'] 1cc per .010 that helps. I work at a place that might have some burettes lying around. I'm sure I can rig somthing that would work and be acurate. Isk Quote Link to comment Share on other sites More sharing options...
JMortensen Posted March 30, 2005 Share Posted March 30, 2005 A lab quality burette (which is what you should be using' date=' check Fisher Scientific) will cost more than the shop should charge you for measuring the chamber volume on 6 chambers. Good grief. The volumes "look" smaller than an E31? Do they know some E88's have E31 chambers? Have them cc it so there's no doubt. Ballpark is every .010 you shave reduces the volume by about 1cc on the '72 version of the E88. The head would have been 4.248 to 4.253 thick stock.[/quote'] If it really is a Gerolamy head it's very possible that the chambers were welded to up the compression. Do you have any pictures of the chambers? I'd like to see what they look like. Quote Link to comment Share on other sites More sharing options...
Guest iskone Posted March 30, 2005 Share Posted March 30, 2005 I don't have anu pics at the moment but I'll get some when I have the head. I think I'm going to buy a real camera today. I'll post pics of some of the stuff people are interested in. Isk Quote Link to comment Share on other sites More sharing options...
yo2001 Posted March 31, 2005 Share Posted March 31, 2005 I had an early open chamber 260Z E88 shaved .080". After milled, it became a close chamber With a dished topped bottom end, it cranked 215-220 psi static with a mild cam. If I remember, it was like 33cc or something. Quote Link to comment Share on other sites More sharing options...
Guest iskone Posted April 16, 2005 Share Posted April 16, 2005 Here are the pics of my head. I just got it back yesterday I cc'd the first chamder and got a reading of 43cc, could be off be a small amount. Also when I did the cc'ng I did not have the spark plug installed I made the spark plug hole smooth. I'm kind of pist that after all the money I spent on rockers, cam tower and all the other BS my head didn't even come back clean. For as clean as it looks I did that myself. I'm going to cc the piston dome today as well and get an acurate CR number I'm thinking it will come back higher then 11.5-1 THe head on the top is the closet example to a stock E88 I have the bottom is my head. Chamber 1 Cahmber 6, looks smaller I have not cc'd it. Quote Link to comment Share on other sites More sharing options...
Synlubes Posted April 16, 2005 Share Posted April 16, 2005 Cahmber 6, looks smaller I have not cc'd it. Measure the head at both ends and or all four corners to see if it is evenly cut. Quote Link to comment Share on other sites More sharing options...
Guest iskone Posted April 16, 2005 Share Posted April 16, 2005 Did the measuring, looks like at its worst the front is .004" larger in height. I don't think that is going to make any difference. It is 4.164" thick Isk Quote Link to comment Share on other sites More sharing options...
JMortensen Posted April 16, 2005 Share Posted April 16, 2005 You're comparing 2 different castings. I've heard that there were as many as 4 different E88 heads. The one you've got is similar to an E31. Some other pics for you: http://www.classiczcars.com/forums/showthread.php?t=13114&highlight=E31 Quote Link to comment Share on other sites More sharing options...
Guest iskone Posted April 16, 2005 Share Posted April 16, 2005 Thanks for the link. Looks like I have an early E88 I just finshed cc'ing the domed pistons and got some weird results. bascilly from my math there is alomost no change. I must have did something wrong. Isk Quote Link to comment Share on other sites More sharing options...
Mack Posted April 17, 2005 Share Posted April 17, 2005 all this talk about CC'ing chambers and what not, I just thought Id pitch in that I and 1 fast z CC'ed a maxima N47 that had not been shaved or altered in any way, with a sparkplug in it the number we got was somewhere between 38 and 39 cc's. the reason for the range is because it was leaking mildly thru the valves. needless to say the head is in dire need of a valve job, lol! I know its not an E88, but its an alternative if your E88 doesnt work out. Quote Link to comment Share on other sites More sharing options...
Guest iskone Posted April 17, 2005 Share Posted April 17, 2005 Hmm thanks for the info. I didn't cc mine with the spark plug in I was thining I wanted the chamber volume to be true but I've beeen thinking that with the spark plug in I'd get a better result. Using the numbers from my head and the numbers from my domed pistons I'm looking at 11.6-1 but that doesn't include the sprak plug so I think I'll do some more ccing. Isk Quote Link to comment Share on other sites More sharing options...
katman Posted April 18, 2005 Share Posted April 18, 2005 4.248-4.164 = .084, that's why what's left of the combustion chamber looks like the E31 chambered E88. Hope you have some thick lash pads to chose from and some slots in the curved timing chain guide to take up the slack. Quote Link to comment Share on other sites More sharing options...
JMortensen Posted April 18, 2005 Share Posted April 18, 2005 I think the open chambered E88 is completely different IIRC. Look at the original two heads you posted pics of Isk. If you cut one down, it wouldn't take on the shape of the other. Your lash pads will be an issue, but this engine was running before so hopefully that was already taken care of. Quote Link to comment Share on other sites More sharing options...
Guest iskone Posted April 18, 2005 Share Posted April 18, 2005 Katman: Lash pads are not a problem they have already been adjusted. What is stock 140? Well Mine are 210 or 220 if I remember. What do you mean by slots in the chain guide? I donn't have those from what I can tell. Trust me there is plenty of tension on that damn timing chain!!! John: Yeah I took a closer look at the 2 heads after you posted the link. The top head is a late E88 for sure. My other other other E88 is an early one too. I think I'm gonna sell off all my spare heads and cams maybe even my other N42 block if someone will buy it. Isk Quote Link to comment Share on other sites More sharing options...
JMortensen Posted April 19, 2005 Share Posted April 19, 2005 Slots in the timing chain guide refers to slotting the mounting holes to move the guide farther than stock. Most aftermarket guides are slotted anyway, but it used to be that you had to slot them yourself. What it allows is for you to move the tensioner out of the way so that you can get the chain on, then you push the tensioner into the chain so that it can't whip around quite so much. This relates to your other post too. Your answer to your question there is that the guide should originally have been set up by someone who had the timing cover off. You shouldn't have to take the timing cover back off to readjust the bottom of the curved guide unless something else changed. Since you're just doing a head gasket, you should be able to loosen the top bolt on the guide with a long 10mm wrench, and pull the guide away from the chain. Then you put the cam gear on and push the guide back over so that it touches the chain, and lock down the 10mm bolt. Quote Link to comment Share on other sites More sharing options...
Guest iskone Posted April 19, 2005 Share Posted April 19, 2005 After thinking about it I realized what you meant, I do have a slotted chain guide. Headed to Shucks now to rent the Universal puller. On a side note I measured the intake open area today and the ports are right around 1.83-1.85" of open area. That's about a 30% increase, intake is ported too. Isk Quote Link to comment Share on other sites More sharing options...
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