Use the thick industrial gauge solder - plumbers stuff . Slight bend on the end to get into the edge and off you go . Looks like you've got a good edge to aim for which will help and don't worry about losing it , that'll never happen if you wrap the excess around your fingers . Done it hundreds of times building bike engines but not on a van - in situ .... Good luck Sent from my SM-G960F using Tapatalk
Original 1700 chamber 49-49.5cc So if he'd done nothing and deck is 3.5 CR would be 8.7 To get 8:1 chambers would need to be 56cc I'm guessing this is about how they are. But he's made them say 60cc and deck is 3.5mm, CR is 7.7:1 I do need to confirm that deck height.
Who knows? I wouldn't run it with blutac in the cylinder though, I'd have to dismantle. 5mm dia sausage, 3.5mm wouldn't squash it too wide to get back out. I can try smaller first just in case it's tighter than I've been informed. I'll be ignoring piston tilt as I'm guestimating chamber size anyway.
Just get the piston an inch btdc , insert your sausage of choice into the edge . Manually turn engine over tdc which will squish the sausage, remove said sausage and measure . It's that easy , I assume you were trying to measure it static ?? Sent from my SM-G960F using Tapatalk
What if... The reason I have so much deck is not that the cylinders are "long", but I have a 66mm crank not a 71mm. 66 x 104 = 2243cc, 55cc chambers, 3.5 deck, 7.6:1.
Your going to be raiding a school laboratory for bell jars and rubber tubes to see how much displacement your actually getting soon.. Sent from my SM-G930F using Tapatalk
You're not wrong! The more I think about that, the more likely it seems. Exactly the same with 71 crank and 0.5mm shims would have 1.5 deck but be 9.9:1 CR. The naughty so and so has found an easy solution to the CR problem, knew I'd be peed off so kept quiet. He had both 71 and 66 cranks that I gave him myself! I should laugh, story of my life, DIY or get screwed. Maybe I'll put him on the spot and see if he owns up.
Have a chat with him otherwise the only other way your going to know exactly how everything is is a complete strip down and measure up
Hang on , I have missed something here - is there a problem with your motor Steve ? Sent from my SM-G960F using Tapatalk
Yes, though not this one and maybe not the engine itself...but maybe. Prepare for the worst and all that. Say I need new heads. If I was doing that, while it was apart I might see if I could tighten the deck depending on the max chamber size AA can supply. To that end I was doing some calculating and suddenly thought "what if?' so calculated that. I'm afraid it all adds up, he was scratching his head then bingo. I was pressuring him to finish it. It still goes alright tbh but not as alright as it once did. What annoys me is that 96 x 78 would have made a stronger similar size engine if I'd wanted a 2250 ish one without carving up the case and heads.
Don’t you know what rods and pistons he used? Rod length, big end dia and/or piston compression height would all be different if the crank was 66 and not 71. What happened to your engine build thread? I had a quick look in modified shizzle but couldn’t find it. 96x80 for the win, no machining and a reasonable deck and CR – with the right cam of course.
I hoped you'd join in. Stock 2l length H-beam rods, stock 2L 35.5mm height 24mm pin. If that 3.5mm deck number is correct and barrels are stock length not "long" then 66 crank works out. If that's correct and I swapped just the crank for a 2L, 71mm I'd have 1mm deck with no shims. What sounds most likely? Freaky 2mm extra long barrels (remembering the exhaust went straight on) or a 66 crank? Also the rocker adjustments look completely typical and wouldn't with 2mm extra barrel length. Stock push rods. I know what I think. (78 x 96 would be easier but too small...like my existing engine. Grr and lol, I have a sense of humour.
Just for your entertainment (and mine), I stuck a little camera in a spark plug hole. Not much overlap with a stock cam.
Sorry to be late to the party – I’ve been camping near the Alps the last few days. 1700/1800 rods are 126mm long with 55mm big ends, 2.0l rods are 131mm long with 50mm big ends so you can’t fit 2.0l rods on a 1700/1800 crank. I doubt if 131mm length rods are available with 55mm big ends and I doubt if a 66mm stroke crank would have been machined to have 50mm big end journals, but either is possible. If the 3.5mm deck is correct my guess is you have a 71mm crank with longer than standard cylinders – or base shims. I don’t think you’d have so much torque at so few revs if the engine capacity was ‘only’ 2243cc, you have almost another 200cc. But the standard rocker geometry is certainly strange. With the piston at TDC measure how much oil it takes to fill the combustion chamber, then with it at BDC see how much more oil to fill the cylinder. It won’t be exact but it will tell you more or less what the cylinder capacity is.
That’s possible; mine are 135.25mm (5.325") with a 22mm pin, but that’s with an 80mm crank and 28.21mm (1.11”) compression height pistons.
Thanks, I didn't know about the different journal sizes. Pin height is 42mm on 66 crank engines so 66 crank/rods with my 35.5 pin height pistons would be at least 6.5mm deck...not that them. Phew!!!
