Hmm I don't know about which piston is actually stronger but but like you said, the higher compression 2g piston is usually favored and have not heard anything about either or being stronger/weaker. Have you also looked at maybe going with the EVO 9 pistons? They are forged and alot lighter than both with a higher compression than the 2g pistons. You can pick up a used set for a good price and get your 1G rods modified to accept then alot like the 2g pistons.

The oem pistons are both cast so one will not be stronger than another. The strength comes in the forging found in aftermarket pistons. The ability to hold power is directly related to the rods since they are what take most of the abuse and they are usually what fail first on a high powered motor. So with that being said the 1g rods are going to be the deciding factor in how much power the motor can handle and not which pistons you have swinging on them.

GRAVEDIGGER said:

The oem pistons are both cast so one will not be stronger than another.

Click to expand...

Just because they were both cast does not mean they are the same strength.

Assuming a 6-bolt engine, are non-turbo pistons not also cast? They use the same rods as a turbo engine; so, by your logic, they should be able to withstand the same power (cylinder pressures) as a turbo piston.

In fact, this is not true. People always say that non-turbo pistons do not like boost. Two major factors are the cause for that: non-turbo pistons have a thinner top ring land than turbo pistons and they provide higher compression. Assuming the same material in any case, thinner top ring land means a weaker top ring land, forever and always. Higher compression provides an interesting outlook on the matter. For a non-turbo piston (9:1 CR), the volume of air entering the cylinder is initially 9 times the final, compressed volume within the cylinder. Realize that on a non-turbo, that incoming air is basically at atmospheric pressure as opposed to pressurized air on a turbo equipped vehicle. It takes more work/force to compress already pressurized air than atmospheric air, meaning the pressures on the turbo piston under boost will be greater than a non-turbo in normal operation.

Which is stronger? I dare say if the turbo piston can hold up to greater pressures due to its design including, but not limited to, piston ring location, it must be a stronger piston.

But we aren't discussing non-turbo pistons, we are comparing 1G and 2G turbo pistons. For simplicity's sake, we will say all 1G engines are 6-bolt and 2G engines are 7-bolt. Disclaimer for the noobs: This is not actually true! 2G pistons have a smaller top ring land compared to the 1G piston as well. The interesting part is, again, the compression ratio. A 2G piston provides an 8.5:1 CR, greater than the 1G's 7.8:1. The difference between the 2G piston and non-turbo piston, obviously, is that the 2G piston sees boost pressures.

Follow the same line of reasoning as the non-turbo piston above for the 2G piston. The 2G piston experiences greater pressures in the cylinder than a 1G piston, assuming all properties are the same for the air brought into the cylinder. This seems to point towards a 2G piston being the stronger of the two, though I do not think that is conclusive evidence to make that determination.

Other factors that have gone overlooked thus far are longevity and increased air flow (boost pressure in particular). Based on my assumptions, sure the 2G piston experiences higher cylinder pressures in stock form. Mitsubishi would not have used any of these pistons if they couldn't last forever in those conditions. But under modified conditions, increased air flow, higher cylinder pressures, etc., perhaps the life longevity of a 2G piston is less than a 1G piston because of that thinner top ring land. On the other hand, perhaps the 2G piston is capable of obtaining higher power levels the 1G piston never sees because of the higher compression it brings to the table. Does that make it stronger or just more capable?

Obviously this is just kicking rocks around, but it gives you more to think about. I cannot say one way or another which is actually stronger. While the 1G piston has a larger top ring land, it has a smaller second ring land in comparison to the 2G. The 2G piston is said to have a ceramic coated dish as well. To answer your question, a 2G piston will be able to make more power simply because of the compression ratio it provides. There are reasons 1G guys upgrade to 2G pistons -- it helps produce more low end power and it is affordable. However, with greater compression comes a greater likelihood for pre-detonation and, consequently, broken pistons. There is always trade-offs in these types of things so choosing the strongest or the best may depend solely on what you wish to get out of the engine.

Here's some threads you can read about the capabilities of both 6-bolt and 7-bolt stock blocks; as you can see, they are perfectly "capable":
http://www.dsmtuners.com/forums/drag-strip/378744-fastest-stock-block-7bolt.html
http://www.dsmtuners.com/forums/drag-strip/382944-finally-hit-10s-stock-block.html
http://www.dsmtuners.com/forums/hangout/383023-mike-rizzotti-9s-stock-block-1g.html
Same as above: http://www.dsmtuners.com/forums/drag-strip/383090-9s-finally-stock-shortblock-internals.html

It is also important to note that the piston strokes are different and account for a part of the compression difference, meaning that the compression ratio of a 2G piston on a 1G rod may be closer to 8:1 than 8.5:1.

I would suspect the top of the 2g piston is thicker than the 1g.

There is a reason that budget builds use 1G rods with 2G pistons. That should answer your question. The rest is research, research, research.

You can get all scientific about it, but they both will handle around the same. Both are proven. 7.8:1 is a little low compression for any car IMO. I run the 1g rod/ 2g piston setup.

1g!!!!!