I own several "classic" jap cars, as such i have had to visit other web sites in the past, let me tell you that Datsun1200 dot com is by far the best.
I have been building up a turbo conversion on my datsun motor recently, before the conversion it only had a few problems, a couple of extra pistons and the cam in the wrong place (L28).
After buy a chinese turbo for my B10 sedan (I realised it was waaaay too big), I thought id put it on uncle cedric (280c).
Now that it all together it has started a rather embarrasing smoking problem I have reduced this problem by replacing the original chinese turbo compressor (dynamic seal) with a compressor and cover from an 13B mazda (positive carbon seal) as this is a draw-thru carby setup on my car ,So there should not be any oil entering from the turbo.
On start-up there is no smoke, occasionally on take off it blows a bit of blue smoke, there is no blue under heavy throttle, but it blows monumental amouts of blue smoke after long periods off throttle (maximum vacuum) it only blows for about a second or so but thats all it takes to make everthing in my rear view mirror to disappear (very embarassing).
When I pull the plugs it appears that its only one clyinder is oil fouling.
I`v replaced all the stem seals (using the old rope trick).
I did a dry compression check and no obvious problems there.
If it was the turbo seal leaking I would assume it would foul all the plugs.
Im leaning toward worn rings but this would not explain the relative similar compression test figures (I repeated the test 3 times) and the suspect cylinder showed the second highest compression every time.
I dont realy want to replace the rings if they are not the problem but I cant see any other option.
So please any comments or thoughts would be appreciated

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