_________________
'15 Chrysler 200S V6
'74 Duster 360, factory 4 speed car

What is the piston pin size on the 2.5 piston.
The main reason I use the 2.2 pistons is because the pin size is the same as the SL6

For any "one-off" hybred engine combo, you need to get enough parts to "mock-up" the combo and take some measurments.
Many piston manufacturers will often send you a sample of an off the shelf piston or ask around for people who work-on those type of engines, many machine shops just throw all their use pistons into a big scrap barrel and I have found interesting options by looking at those.
DD

There are three kinds of basic pistons in 2.2/2.5

2.2 is what you are famillar with, 81-94. If you need flat tops, get one for carbed 2.2 (81-88 ), need dished, use turbo or TBI for different dish depths from the 2.2 or the common block 2.2 pistons (n/a or turbo).

Tall deck 2.5 uses 2.2 pistons with deeper dish and long rods (almost like turbo 2.2 pistons), three year deal: 86-88.
2.5L used in common block using same rods as 2.2 and use 2.2 deck height but the 2.5L pistons pin location moved up and a stroked crank (different casting), 89-95

Oh the wrist pins are same size for all. In fact, you still can find flat tops for neon 2.0 or 2.4 used for performance applications. Same wrist pin size and piston bore (3.44").

Small end of rods size determines the wrist pin as press fit or floating.

Cheers, Wizard

I do know that the difference in pin height between the 2.2 and the 2.5 on the one I did was around .220 or so. The machine shop put 2.2 pistons on the rods and I had a deck height of +.200". When he put the right 2.5 pistons on it was -.020".

_________________
Official Cookie and Mater Tormentor.

What combination is that (block, rods, crank)? Flat top pistons or dished?

Sounds about right, CH numbers I have been using are 1.5945" for a 2.2 and 1.37" for a 2.5. Difference would be .2245".

As noted, 2.2 and 2.5 rods are all identical (minus the tall block 2.5 rods), and in fact, all later 2.5 turbo motors got the same rods as the 2.2 T2 motors, including the full floating piston rods. So, if the 2.2 rods use the same piston pin as the /6, the the 2.5 matches as well.

_________________
'15 Chrysler 200S V6
'74 Duster 360, factory 4 speed car

I was told the later 2.2/2.5 used the same pistons and that the one I did was an early version. All I know is that it wasn't the original motor to the car. Car was a '94.

_________________
Official Cookie and Mater Tormentor.

Ah, you weren't talking about a /6. My mistake.

The later 2.2 and 2.5 do not use the same piston, they use the same rod. Longer stroke requires a shorter piston. I think even the tall deck 2.5 requires a different piston as at least the dish would need to be larger to keep the compression comparable.

Don't look in the Mopar 2.2/2.5 book, though. It says the 2.5 all use a 40.5mm CH piston. With a 1/2" of more stroke, the piston has to be shorter.

_________________
'15 Chrysler 200S V6
'74 Duster 360, factory 4 speed car