Arais flat tops help

[Tzclark]

I have a question about Pistons that have been sitting around for awhile. They were made years ago so arais has no info on them. They are 60 over flat top but they also list a 4" stroke, can someone explain the 4" stroke listed? Lack of knowledge might be the issue here but why would a piston list stroke?

 

[Seax440Dodge]

different strokes will cause the wrist pin to have to be in a different location, if you put a piston designed for say a 3.75 stroke on a longer rod, everything will stick out the top of the deck when it's at TDC. So those pistons are designed to be used with a 4" stroke

 

[Tzclark]

Can you give me an example of a crank and rods that would work with these?

 

[Seax440Dodge]

what's the application? (small block? big block? what's the bore?)

a .030 over 360 w/ a 4" stroke would yield a 408

 

[Tzclark]

Big block Rb, 4.380, street not race

 

[lewtot184]

back before stroker cranks were available people would take a stock crank and weld it up to increase stroke. the pistons you have are probably for this type of crank. measure the distance between the center line of the wrist pin hole to the top of the piston and then rod length can be determined. i'm pretty sure it will be for a stock length rod but measure to be sure.

 

[66Satellite47]

Measure the distance from piston top to centerline of wrist pin. Then you can back calculate the stroke & rod length that the piston was designed for. I used Arias pistons in my first low deck 452 motor & they were top notch quality.

 

[Tzclark]

I am not interested in using them but wouldn't mind selling them. I've heard they are great pistons. I will get the calipers out next time I am in the shop. I just want to be educated so that when I do sell them the purchaser has full knowledge. I guess the question is, are they worth anything to anyone?

 

[66Satellite47]

Maybe, depends on what they fit. Piston top to pin centerline tells what motor they work with.

 

[lewtot184]

may be hard to find someone with a 4" rb crank now days. doing the math on them; it's possible they would work in a stock stroke 400.

 

[Tzclark]

I looked around the web and can't find much, I'll measure them and post back.

 

[Tzclark]

They appear to measure 1.93 plus or minus a few thou from center of wrist pin to top of piston.

 

[Tzclark]

I made a mistake typing, they are 1.91, compression height. That is stock for a later 440 is it not?