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definitely not overheating it and running cooler would probably help too, but im not too sure about grinding anything off that area, its not that thick from what I've seen to begin with!

its also nearly the hottest part of the cylinder with all the exhaust gasses going in and out past it!! so up against it from the beginning.

My understanding is smoothing out sharp points in the combustion chamber reduces hot spots.

the metal is thin there but thin from valve to valve, quick thick vertically which is the direction is cracks.

well from what I've seen no its not, its thick around each valve but there is a groove close to the bottom that runs between the two valves that is the weak point, and from what I've seen on a die ground out one, its only about 2mm before you hit the water jacket in this area.

I would love to have one sliced in half to see for myself.

Yeah sharp edges are stress raisers for sure, can usually radius them without decreasing the cross sectional area enough to weaken it.

charlay86 wrote:Yeah sharp edges are stress raisers for sure, can usually radius them without decreasing the cross sectional area enough to weaken it.

its would take bugger all to radius it. About 2 sec with a die grinder, very minimal material just to take the sharp edge off.

The edge is a result of the valve seal angles from both seats overlapping

Back on the oil topic i got a 20L Drum of 15w 50 for a good price, so have just done a service and changed back, will be interesting to see if the oil test goes back to normal, im thinking it's just the additives in 5/50 not liking our engines and breaking down quicker.

Been to busy of late at work to have time to even strip the engine down, might get to that in a couple of weeks if i get one off.

Trans is going good, still slipping a little on takeoff nothing serious only me being pedantic in the logs, but a few thousand km's on it now and all good, think ill pull the pump out and check the seals etc when the engine swap happens. Definatly 1000% better than my old worn box, i can tell now after driving mine with a built box and going to wifes wagon with a stock box and vette servo it's so god damn lazy and sloppy with the shifts, mines so nice, not harsh but super accurate, click click click through the gears

Good stuff, sounds like its working very nicely.

The1 wrote:Definatly 1000% better than my old worn box, i can tell now after driving mine with a built box and going to wifes wagon with a stock box and vette servo it's so god damn lazy and sloppy with the shifts, mines so nice, not harsh but super accurate, click click click through the gears

i went the other way, from a kitted T700 to a worn 4L60E, was very painful

pulled the L67 down, only crank and ballance shaft left to get out, only #6 spun bigend bearing. Though havn't pulled the Main caps off yet. I wouldn't say the bolts on the mains both cap and side were tight, side ones were like butter. So perhaps allowed the crank to move back and forward?
Gaskets shot as expected for plastic ones, looks clean the internals All lifters look ok, though not sure inside i have new ones anyway #6 on the left who did the bigend #6 top end looks different colour, like its was running hotter? Would have been out of timing with bearing gone? Other side head/pistons Cam #3 & 4 are like this, the others are ok (just lack of oil cause this?)