1.6 1.8 - Same Tourqe limit ?
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Hello together,
my name is daniel, i'm from germany. i'm fairly new to this forum. i drive a 99 1.6 nb with a td04l-13t turbo at 10psi (21 degree timing BTDC at redline). runs pretty fine for nearly 30k kilometers now.
I had a hefty discussion with some friends of mine, regarding the power limit of the stock 1.6 and 1.8 liter engines:
- We all know, the first thing that will happen, when driving with extreme high low-end-tourqe is -> conrods, in the shape of a banana, flying through your block into outa space, reaching Saturn, maybe Jupiter... after some hours of traveling....
Now on a 1.6 and 1.8 the rods are the same, and stroke of the crankshaft they are "operating" ist also nearly the same (difference of 1,4mm; so a actual leverage difference of 0,7mm) .
So the point is, if the rods are, apart from the other parts of the engine, the first things to fail, and the they are indeed the same, shouldn't both engines be able to push the same torque savely at the crank? the torque is just the product of the rod pushing at the lever(the crankshaft). so for my understandig, if the rod gets pushed by a big piston with 10psi forced induction or a small piston with 15psi forced induction, shouldn't make any difference at all, for the rod. am i right ?
can somebody confirm that the 1.6 and 1.8 have the same torque limit, or if not, can someone please tell me WHY the torque limit is higher on a 1.8 than on a 1.6 ?
Thanks in advance
Daniel
my name is daniel, i'm from germany. i'm fairly new to this forum. i drive a 99 1.6 nb with a td04l-13t turbo at 10psi (21 degree timing BTDC at redline). runs pretty fine for nearly 30k kilometers now.
I had a hefty discussion with some friends of mine, regarding the power limit of the stock 1.6 and 1.8 liter engines:
- We all know, the first thing that will happen, when driving with extreme high low-end-tourqe is -> conrods, in the shape of a banana, flying through your block into outa space, reaching Saturn, maybe Jupiter... after some hours of traveling....
Now on a 1.6 and 1.8 the rods are the same, and stroke of the crankshaft they are "operating" ist also nearly the same (difference of 1,4mm; so a actual leverage difference of 0,7mm) .
So the point is, if the rods are, apart from the other parts of the engine, the first things to fail, and the they are indeed the same, shouldn't both engines be able to push the same torque savely at the crank? the torque is just the product of the rod pushing at the lever(the crankshaft). so for my understandig, if the rod gets pushed by a big piston with 10psi forced induction or a small piston with 15psi forced induction, shouldn't make any difference at all, for the rod. am i right ?
can somebody confirm that the 1.6 and 1.8 have the same torque limit, or if not, can someone please tell me WHY the torque limit is higher on a 1.8 than on a 1.6 ?
Thanks in advance
Daniel
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I would guess that the 1.8's limit is slightly lower since it has a lower rod ratio (IOW, the rod is at a greater angle in relation to the piston during the combustion stroke). Having said that, the difference between the two is well within the noise of the data. Picking a 1.6 because it's theoretically stronger would be very misguided.
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