100mm barrel options...

[Porschekid962]

I could go with the Mahle set but I would rather have custom pistons.

Then there is LN engineering with their very nice product.

Can 3.2 barrels be opened up to 100mm or is that just asking for problems?

How about using 3.6 barrels on an older case, need to machine out, move headstuds around, bla bla bla.

I have a set of 993 p&c's. I have a 78 3.0 to use or a euro spec 3.2. Then there is the 964 twin plug dizzy and 95 993 plastic intake all boxed up and hidden away. So many ways to go and so many ideas mean that I am getting distracted such a tough life. Oh and the gt3r oil pump still in it's plastic along with some other goodies I found cleaning up the shop.

So I was thinking of replicating to some extent what Henry did with his mfi 3.5 only go the efi route. 3.0 rods on the 3.2 crank, calico bearing, supertec headstuds, twin plug, 11.5:1 cr JE pistons, 993 heat exchangers, gt3r pump, hot cams, head job, bla bla bla all until I can get some time on the cnc at school and run off my itb's. At this point the LN nickies are looking pretty good but what does everyone else think?

yes this motor is going to take a while longer but it will be built i have almost all the nonsense for it just need to finalize a few things and get a free stand at the shop and get goin. thanks all, btw its going in a sub 2000 pound car.

cheers, ryder

[cnavarro]

Like you thought, boring out the stock 3.2 cylinders is a bad idea. At 100mm, that leaves you with a case spigot of 103mm which means the skirt is roughly ~102.9mm. The actual aluminum thickness on average would be deducting for plating thickness would be 102.9-100.2, or 2.7mm, or 1.35mm per side. Just to give you a point of comparison, i've made custom Nickies before with just over 1mm per side, but you have to consider cast vs. extruded material properties, strength, and fatigue life, etc. The case register of a standard 3.5 conversion cylinder is upped 2mm, to give you added skirt thickess, so that they don't break off in the case like thin cast vw cylinders do on a regular basis. Those cylinders ended up in a hot rodded vw about 4 years ago and are still running strong. So I guess it would be similarly possible to make a slip in Nickies 100mm that wouldn't need the case machined, but no one ever wants to be a paying guinea pig :-)