SVX Network Forums Live Chat! SVX or Subaru Links Old Lockers Photo Post How-To Documents Message Archive SVX Shop Search |
IRC users: |
#46
|
|||
|
|||
Re: 11:1 Engine Rebuild
Quote:
Looks like the crank worked fine out-of-round, It comes down to whatever you can live with, as it seems the engine was able to live with it. As for machining the deck surface, with 187K, the surface is not likely to 'clean' with a .0015" cut, considering aluminum and 'floating' cylinders. The idea is to cut the same from each deck, unless going to the trouble to measure each corner and 'blueprint' the deck. LAN has done a few, he would have a better perspective than I would. However, .006 sounds very reasonable for clean, flat and true Did LAN supply the pistons? If so, ask him about the deck surface, he should be happy to comment about the .006" cut.
__________________
Special Thanks to Our Friends and Sponsors: * http://www.alcyone.org.uk/ssm http://www.PhenixWheels.com http://www.dba.com.au/ http://www.ClassicSoftTrim.com http://ToyoTires.com/tire/pattern/versado-lx Gillman Subaru of Houston "QuickChange" http://www.TransGo.com/ http://www.PlanetSVX.com Bontrager Works, '92 Subaru SVX LS-L Claret ORIGINAL OWNER '92 LS-L Pearl~ '92 LS Pearl~ '92 LS-L Teal~ '92 LS-L Silver~ '95 LSi Polo~ '92 JDM Alcyone SVX Version-L 4WS Pearl~ http://www.subaru-svx.net/forum/showthread.php?t=54143 '92 JDM Alcyone SVX Version-L 4WS Ebony~ http://www.subaru-svx.net/forum/showthread.php?t=54117 |
#47
|
|||
|
|||
Re: 11:1 Engine Rebuild
I have asked LAN about the cut, and he said I would have to feel for contact between the pistons and heads. He didn't seem to think it would be a problem though.
As for being out of round, with the oil clearances where they are, I am going to say it is going back together as-is. Like you said, it worked before. And I am not taking it much past the stock RPM range, and even with the increased compression, it should survive. I am masking everything off (heads and block) for paint now. Once the enamel is fully cured I will begin reassembly. I know there are a couple tiny pieces I will be forgetting, but save waiting for parts this build is about to begin. I will post pictures of my progress as I get the chance.
__________________
Cam '92 Ls-L Dark Teal 11:1 CR ECUTUNE pistons ECUTUNE .256 duration intake/exhaust cams ECUTUNE STAGE 2AV1 ECU Z32 MAF/SR20DET injectors Balanced & Blueprinted |
#48
|
|||
|
|||
Re: 11:1 Engine Rebuild
Quote:
LAN knows the piston specs, so, whatever he says. If Piston has stock compression distance [pin center to top] and you are using stock headgasket, .006" removed may be perfect for octane tolerance with 11.1:1. Again, whatever LAN says, he would know the specs Waiting for pictures
__________________
Special Thanks to Our Friends and Sponsors: * http://www.alcyone.org.uk/ssm http://www.PhenixWheels.com http://www.dba.com.au/ http://www.ClassicSoftTrim.com http://ToyoTires.com/tire/pattern/versado-lx Gillman Subaru of Houston "QuickChange" http://www.TransGo.com/ http://www.PlanetSVX.com Bontrager Works, '92 Subaru SVX LS-L Claret ORIGINAL OWNER '92 LS-L Pearl~ '92 LS Pearl~ '92 LS-L Teal~ '92 LS-L Silver~ '95 LSi Polo~ '92 JDM Alcyone SVX Version-L 4WS Pearl~ http://www.subaru-svx.net/forum/showthread.php?t=54143 '92 JDM Alcyone SVX Version-L 4WS Ebony~ http://www.subaru-svx.net/forum/showthread.php?t=54117 |
#49
|
||||
|
||||
Re: 11:1 Engine Rebuild
Bet these guys would have the answers---IF they would share.
http://www.youtube.com/watch?v=KhGu0...eature=related Oh, to have some major bucks. Lee
__________________
SVXx2 92 SVX LS-L Silver 92 SVX LS-L Burgundy (structurally challenged with 2792 miles) 96 SVX LSi Red 92 SVX LS Pearl (Parts) 01 F150 4X4 Red (+6 with other members of the family) FREEDOM IS NOT FREE |
#50
|
|||
|
|||
Re: 11:1 Engine Rebuild
They are taller than the stock pistons, IIRC. I can verify that though pretty easily. When I put the short block together I am going to measure to the best of my ability how far the piston protrudes from the decks, and then subtract my clearances on the head.
Depending on what I see, I may shim the heads (I could probably get myself some .006" titanium and seal it to the block after gasket matching it). The other option is find an aftermarket HG that is slightly thicker than ours. (COMETIC?) I may have plenty of room...we shall see once the short block goes together.
__________________
Cam '92 Ls-L Dark Teal 11:1 CR ECUTUNE pistons ECUTUNE .256 duration intake/exhaust cams ECUTUNE STAGE 2AV1 ECU Z32 MAF/SR20DET injectors Balanced & Blueprinted |
#51
|
|||
|
|||
Re: 11:1 Engine Rebuild
Quote:
You would not be able to visually see the difference to say the pistons are taller than stock, that must be measured.
__________________
Special Thanks to Our Friends and Sponsors: * http://www.alcyone.org.uk/ssm http://www.PhenixWheels.com http://www.dba.com.au/ http://www.ClassicSoftTrim.com http://ToyoTires.com/tire/pattern/versado-lx Gillman Subaru of Houston "QuickChange" http://www.TransGo.com/ http://www.PlanetSVX.com Bontrager Works, '92 Subaru SVX LS-L Claret ORIGINAL OWNER '92 LS-L Pearl~ '92 LS Pearl~ '92 LS-L Teal~ '92 LS-L Silver~ '95 LSi Polo~ '92 JDM Alcyone SVX Version-L 4WS Pearl~ http://www.subaru-svx.net/forum/showthread.php?t=54143 '92 JDM Alcyone SVX Version-L 4WS Ebony~ http://www.subaru-svx.net/forum/showthread.php?t=54117 |
#52
|
|||
|
|||
Re: 11:1 Engine Rebuild
I have the tools to measure that, as well as a spec sheet that came with the new pistons. Being that they are 11:1 pistons as opposed to 10:1, the diameter was increased, and I believe the height as well. I have my old pistons still and my new ones laying in the garage wrapped in foam. I will go check them once the paint on the block and heads is applied. I am almost done masking...what a tedious process.
With respect to LAN, I will not post any actual dimensions on the pistons. Only whether or not they are changed. Pics are a different story though
__________________
Cam '92 Ls-L Dark Teal 11:1 CR ECUTUNE pistons ECUTUNE .256 duration intake/exhaust cams ECUTUNE STAGE 2AV1 ECU Z32 MAF/SR20DET injectors Balanced & Blueprinted |
#53
|
||||
|
||||
Re: 11:1 Engine Rebuild
You might want to take thermal effects into account and consider laying the head back a tad to ensure that the pistons tops don't come in contact with them.
-Bill
__________________
Retired NASA Rocket Scientist Most famous NASA "Child" - OSIRIS-REx delivered samples from asteroid BENNU to Earth in Sept. 2023 Center Network Member #989 '92 Fully caged, 5 speed, waiting for its fully built EG33 '92 "Test Mule", 4:44 Auto, JDM 4:44 Rear Diff with Mech LSD, Tuned headers, Full one-off suspension '92(?) Laguna, 6 spd and other stuff (still at OT's place) My Locker |
#54
|
|||
|
|||
Re: 11:1 Engine Rebuild
That is what I am worried about. By taking the material off the decks, the heads have moved close to the CL of the engine. Pistons will not have moved though, tightening up the room between the pistons and the heads.
What do you mean by laying them back a tad?
__________________
Cam '92 Ls-L Dark Teal 11:1 CR ECUTUNE pistons ECUTUNE .256 duration intake/exhaust cams ECUTUNE STAGE 2AV1 ECU Z32 MAF/SR20DET injectors Balanced & Blueprinted |
#55
|
|||
|
|||
Re: 11:1 Engine Rebuild
METHYL ETHYL KETONE!
the answer for all your paint mistakes
__________________
Cam '92 Ls-L Dark Teal 11:1 CR ECUTUNE pistons ECUTUNE .256 duration intake/exhaust cams ECUTUNE STAGE 2AV1 ECU Z32 MAF/SR20DET injectors Balanced & Blueprinted |
#56
|
||||
|
||||
Re: 11:1 Engine Rebuild
Quote:
Hope this makes sense. -Bill
__________________
Retired NASA Rocket Scientist Most famous NASA "Child" - OSIRIS-REx delivered samples from asteroid BENNU to Earth in Sept. 2023 Center Network Member #989 '92 Fully caged, 5 speed, waiting for its fully built EG33 '92 "Test Mule", 4:44 Auto, JDM 4:44 Rear Diff with Mech LSD, Tuned headers, Full one-off suspension '92(?) Laguna, 6 spd and other stuff (still at OT's place) My Locker |
#57
|
|||
|
|||
Re: 11:1 Engine Rebuild
Makes perfect sense. I will have to make a judgement call once my short block is all together. Won't be long now. Paint is drying. I can handle it in 3 hours, but I probably won't start assembling it until tomorrow or thursday.
I really don't want to remove material off the pistons, they are thermal coated and that was not cheap. Is shimming a viable option? I just measured my head gaskets and they are .066" thick...same as cometics maybe they would throw another layer of steel in there for me...?
__________________
Cam '92 Ls-L Dark Teal 11:1 CR ECUTUNE pistons ECUTUNE .256 duration intake/exhaust cams ECUTUNE STAGE 2AV1 ECU Z32 MAF/SR20DET injectors Balanced & Blueprinted |
#58
|
||||
|
||||
Re: 11:1 Engine Rebuild
Quote:
Do not gamble....measure the compression height of those pistons and calculate your CR properly. One should not use a shim on the head gasket to obtain proper deck clearances on the pistons. Not that it can't work, it's just not the right way to be doing this on such a motor. Proper way to do it is to flycut the pistons to achieve the right clearance. CC chamber, measure CH and DH, calculate requires specs(CR, piston height, etc, etc). Machine/correct CR as needed and rebalance. Just my thoughs in a nutshell over dinner here |
#59
|
|||
|
|||
Re: 11:1 Engine Rebuild
Thanks for the input Boxersix.
I am trying to get a hold of cometic. Since they make custom gaskets, I am going to get a price quote on some EG33 gaskets .070" thick. Just in case I need them. By flycut the pistons are you talking about removing height off the dome?
__________________
Cam '92 Ls-L Dark Teal 11:1 CR ECUTUNE pistons ECUTUNE .256 duration intake/exhaust cams ECUTUNE STAGE 2AV1 ECU Z32 MAF/SR20DET injectors Balanced & Blueprinted |
#60
|
||||
|
||||
Re: 11:1 Engine Rebuild
Best to alter the head rather than the piston IMHO. I personally would make the measurements and add a safe amount of expansion clearance and order a custom gasket from Cometic.
Tom |
|
|