Stroker Project Final Check up

[yeomgon]

After months of talking I've finally managed to gather all the parts I THINK I need to do this project. So here it goes:

M50TUB25 Block
M50TUB25 Pistons X 6 ?
M52 Piston Rods X 6
S50 Crankshaft
24# Injectors X 6
Misc. Gaskets
ECU tune from AA
Dr.Vanos Stage II

and

MLS Headgasket(not purchased yet)

So this is a Vanos 2.9L stroker based on 325i using S50 Crankshaft. However, I have three more questions that I need to take care of.

1)I am thinking of boring the cylinder into 84.48mm, whilst using .48mm oversized piston rings on M50 Pistons(84mm bore). Would it be wiser to not bore it and go with the standard size pistons?

2)To my calculation, the piston will stick out 0.4 mm out of the block. Therfore I am planning to shave the piston by 0.4mm. If I use stock headgasket my compression ratio would be closer to 11.8:1. Which headgasket should I need?

3)Is there something that I am missing here?

[TCarlisle]

In your calculations, have you taken into consideration heat expansion? If the piston sticks out of the block and you shave just that amount, what happens when it heats up and things expand? Also from below it sounds like you might end up with a lot of pisto to cylinder clearance. A machine shop might be able to tell you what the clearances should be.

My pistons are notched to creat clearance for the valves. So if I were to stroke it and just shave the surface of the pistons, if I didnt also increase the depth of the notch I would smack a valve. Has all the homework been done on all this?

[yeomgon]

Originally Posted by TCarlisle

In your calculations, have you taken into consideration heat expansion? If the piston sticks out of the block and you shave just that amount, what happens when it heats up and things expand? Also from below it sounds like you might end up with a lot of pisto to cylinder clearance. A machine shop might be able to tell you what the clearances should be.

My pistons are notched to creat clearance for the valves. So if I were to stroke it and just shave the surface of the pistons, if I didnt also increase the depth of the notch I would smack a valve. Has all the homework been done on all this?

I am thinking that the stock clearance calculation has taken the heat expansion issue into consideration, right? Since my calculation is based on the stock clearance, heat expansion won't be too much of trouble. Now, after hours of thinking I still can not decide which headgasket to use. Although the thickest I can find is 3.98mm, the thicker it gets the lower the compression. My goal is to have a CR of 11.3~11.5. I am squeezing numbers in but the only problem is that I do not have any data as how the HG thickness will affect the CR ratio. All of my calculations are based on 'if' the HG is at stock thickness.

Anyone else might want to add to this...?