Speed Pro 3400 V6 Hypereutectic Pistons

[bob442]

first off, what do you want? you can achieve any other compression ratios with the speed pro pistons than i already stated, which is 9.5:1 or 9:1 or 12.5:1 or 12:1, (the first sets of numbers are for a 3400, second are for a 3400/3500 hybrid, which has 3500 heads with larger combustion chamber)
you seem to have a lack of understanding of how you get a higher CR, in laimest terms its making the combustion chamber size at TDC (Top Dead Center) smaller or larger. So a piston with a lower pin height is going to have a higher CR, As the whole piston has moved up. figuring out all this information for yourself is kind of a pain in the ass, but its possible.
If you select 3.4 iron head in the CR calc. you will have your values for the piston dome volume, same goes for the 3400.
when i wake up i might figure the whole equation out again

[GrandAmGTTT]

I understand that to increase compression you must move the piston up, and increasing the size of the combustion chamber allows for more air to be compressed. I am just having trouble calculating how to get the compression i want using the 3400 heads. Apparently i cannot get the compression i want (11.5 or greater) using the speedpro pistons, that is my understanding of that unless i use the 3500 heads correct?

sorry i am slow at understanding lol i just want to learn

[bob442]

you can get 12:1 with RWD iron head pistons and 3500 heads thats as close as you'll get with out spending some $ on custom pistons.

[mfuller]

I understand that to increase compression you must move the piston up, and increasing the size of the combustion chamber allows for more air to be compressed. I am just having trouble calculating how to get the compression i want using the 3400 heads. Apparently i cannot get the compression i want (11.5 or greater) using the speedpro pistons, that is my understanding of that unless i use the 3500 heads correct?

sorry i am slow at understanding lol i just want to learn

Okay, here's the deal:
There are basically 6 options (some maybe used in combination) if you want to increase compression, but not all are necessarily feasable with this engine.
1. Decrease the size of the cylinder head combustion chambers
2. Decrease the size of the piston dish
3. Change the piston pin location (move it lower in the piston) to push the piston up higher
4. Use a longer connecting rod
5. Use a thinner head gasket
6. Get a crankshaft with a longer stroke

3500 heads use a larger combustion chamber than 3400 heads, so if everything else remains unchanged, the compression ratio decreases.
You'll have to work the math of different combinations to acheive what you want.

[GrandAmGTTT]

k thanks guys!