inxs
Parking Attendant
Posts: 11
|
posted August 05, 2006 07:22 AM
1270 ring gap/milling head
I picked up my block from Millenium & I checked the ring gap on all 4 holes.Top ring is .012"-.013,second ring is .013-.014" From experience,does anyone have info on proper ring gap?Pistons are Wiseco 2.5mm over with a c.r. of 13.5-1 Any other assembly advise would be appreciated.I'm also considering decking the head instead of eliminating the .010 base gasket.Can you take off .010 and still have safe clearance and run 92 octane? The Wiseco pistons look more finished than they did in the past. CW
  
|
droid
Expert Class
Posts: 133
|
posted August 05, 2006 08:10 AM
Standard piston ring gaps are
0.009 to 0.016" Top
0.016 to 0.022" Second
if this helps
Service limit 0.03" top and 0.031" second
|
Y2KZX12R
Needs a job
CompetitionCNC.com
Posts: 3762
|
posted August 05, 2006 09:30 AM
Removing the base gasket and milling the head dont do exactly the same thing.
The compression bump would be the same.
But milling the head wouldnt tighten the squish areas. It doesnt change the deck height.
Forged pistons rock in the bores when cold and on some engines you can here a "knocking" or ticking noise when cold. They require more skirt clearance when cold vs. the cast stock pistons. Once they heat up to temp they tighten up and are ready to be hammered on. So do a mockup and measure the rocking action without the rings on a piston when checking the deck height on forged pistons.
This is why you should never rev up a cold engine with forged pistons.
____________
Y2KZX12R
CompetitionCNC.com
|
|
|
HOME
NEW TOPIC