How inaccurate could a 20cc syringe the Chemist gave me be? Very I think so I'll have to wait for the posty to deliver a burette. If it's accurate 47cc + 2cc for the pockets 3.7mm deck (new battery in vernier) 104x71 8.5:1 47cc I don't believe BTW. Frustrating.
Why don't you believe it? Fill syringe twice, squirt into head, fill a third time, squirt until full, then do simple subtraction. What am I missing on, where that can go wrong?
I didn't trust (couldn't read very well) the 60ml syringe I had.. so weighed it before and after on the kitchen scales at 0.1g accuracy 1g = 1cc Sent from my SM-G930F using Tapatalk
Have you got a set of digital kitchen scales? If so the specific gravity of water is exactly one so 20grammes is exactly 20cc or 20ml etc. So set of digital scales with one decimal place
1700 heads are meant to be 49.5cc before the chambers were enlarged. Exactly as you say 20+20+7. Did it twice. He has decked them a bit though?
I don't have scales sadly...but just checked syringe against a medicine measuring cap and they agree. 8.5:1 it is then...ish. Now I need to make more effort with the deck measuring.
Anyone got a vernier, a 1700 head and 5 minutes? I'd like to know... Depth of the cylinder register from that thicker bit surrounding it. Depth from there back to the fin surface. He also milled that whole fin but from there to the the bottom I have about 6mm.
Perimeter wont effect your combustion chamber? Any resurfacing just takes hole away. Sent from my SM-T580 using Tapatalk
I think zedders meant the perimeter of the combustion chamber. But I could be wrong. You can see in the ‘work in progress’ pic that one chamber has been opened up opposite the spark plug, the shallowest part.
Exactly that. What do you think of my minimum 8.5:1. If I bolt the barrel down to measure the deck it might increase.
8.5:1 is probably too high for a standard cam. I’d aim for 8.0:1 and it wouldn’t take much to open up the chambers a few cc – something for you to do on the boat while you’re waiting for the rain to stop? Incidentally, I think it was Wreck that said you could dish the pistons. A shallow dish down to the depth of the valve cut-outs would help a lot and would avoid taking more out of the combustion chamber.
The dish in the piston isn't just a cut out.. you can see the recess on the back face so not sure how thick the top is.. I considered it on my AA's trying to ease me CR Plenty to go at each side of the spark plugs. Sent from my SM-T580 using Tapatalk
Burette coming later this morning, but it's going give the same result. These pistons can't be dished, not enough meat, as Deefer says. I need to have the heads decked true which will reduce the chambers even more, then find 10cc plus whatever is lost decking them. And that's WITH the huge deck height. I honestly don't think it's a sensible thing to try, even if it were possible. Attempting squishable deck? Hahaha. It's been educational to have my head in my hands (see what I did there? ). There's so little left of it even now, I'll show with photos/vernier later. EG between the fins where it's cut for the barrels, another 2-3mm radius on the 115mm dia cut and you'd be right through.
