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You'll need to actually measure the surface finish. There is a tolerance requirement for the finish, and if it's out of spec, the head gasket might not seal up. Which head gasket are you going to use - stock or cometic?
Was going to go stock, but whatever might make it work best. How do you measure? I would certainly not want this machine shop to do it.
Perhaps I could use a belt sander to fix the finish....jk
It will have to be done by a machine shop. These are very specialized instruments that can be incredibly expensive. If the roughness wasn't so obvious from pictures, I wouldn't bother to mention it, but after seeing those pics I would be concerned about even the stock HG sealing up. I think you need to aim for a roughness average of 50 Ra.
As far as cometic vs stock, I will have to defer to the builders on this forum. I think the majority of responses will recommend the stock HG for this rebuild. You'd have to pay a lot more money for a mirror-like finish on the gasket surfaces to use an MLS gasket like the cometic.
Hopefully others will chime in here and I don't mean to be a doubting Thomas, but I thought I should mention it here. I picked up a sleeved block recently. The story I got: it was tore down after ~20K miles because the owner had it on track and it started spewing blue smoke so they flagged him. Steel sleeved block with stock pistons/rings and apparently the rings wore down (cylinder walls look like they need to be homed again too).
I'm looking to go the stroker hybrid route with it but am not sure if the walls are thick enough to bore it out for a 2.8...
Well I have been on a trip for a week so far. What was supposed to be a 4 day trip to U.K. and back turned into another mission from UK, Spain, Lajes, then home. Figures we broke the second to last day in Lajes. Turns out that we cannot control one of our 6 hydraulic pumps due to a failed solenoid in the pump itself, so we are awaiting a maintenance person to come out with the solenoid to fix it. But it has been a fun trip so far.
Last post for the day... this has been beginning to concern me. That one scratch on the block, will that seal up? I remember being able to feel that scratch. My guess is it is about 2-3 thousandths deep. They already took 6 off. I'm looking in the manual right now for the limit of how much can be decked, but how thick of a head gasket can one use if this is salvageable?
If I have to get a used block, I am going to this shop and requesting reparation as well as a refund for their mistakes.
eh.. Don't want to ruin your world, but if that's what you've seen out the window over alps, you are still missing a lot.. I've been flying on the jumpseat last year quite a few times over the Alps, and the air was much clearer and the view usually is astonishing - more like:
I never made a picture though this image was found on google and is from http://velvetescape.com/2012/04/plan...european-alps/
btw i may be wrong but your photos don't look as high as FL390.. more like 290... ;P
in other words: you have to visit the old continent again, my dear overseas folk!
sorry for the offtopic i can't help you on the gasket question though
I have been reading up on what hondadustr did to deglaze his alusil cylinder walls. Looks like he basically used a honing stone covered with scotchbrite pad and etched the aluminum between the silicon. Anybody have any success with this?
just saying, can't wait to start working on this engine. I will hopefully get home in a month or so.
been talking with Mike down in Maryland about doing the machining on it. sounds like he really knows his stuff. no more back country machinists touching my block.
06-06-2014, 04:29 PM
this image was found on google and is from http://velvetescape.com/2012/04/plan...european-alps/
i can't help you on the gasket question though 
