Quote:
Originally Posted by deansbimmer
It's so easy a caveman can do it! 
Check out some stroker build threads if you want to pursue. Custom rods and pistons are a requirement. You can't change the stroke without them. And you don't need sleeves either. Most 4.6 S65's run on stock blocks bored to 94mm, most builders will suggest that over sleeves anyway.  |
You *can* change stroke with stock length rods, I have on 1 S85 I've built, and one of the two other's I'm waiting on parts still, but for god's sake, don't use OEM rods.
Most limit the stroke increase to 83mm though on stock length rods though as going beyond 93mm requires either using smaller diameters wrist pins (not desirable) or using wrist pin buttons on the piston due to moving the wrist pin location up into the piston far enough it invades the oil control ring groove. See below for what I mean:
It's more a matter of what you are ok with for rod length/stroke ratio. It's cheaper to use stock length rods anyway, since they are usually an off the shelf item.
The real trick with a 94mm bore is going to be sealing between cylinders. I'd love to see pictures of an S65 block deck with 94mm bore after 20-30k miles. I'm betting you'll see signs of inter-cylinder blow-by.
On the same note, I'd like to see a sleeved S65 or S85 with over 60k miles on it. IMO, sleeving these is a solution for a problem that hasn't been identified yet.