Hi, I just got a 227k mile SC400 and once I have some more dough lying around I'd like to go for a high compression N/A build.

I'm making this thread to ask about the many different way's I've found of making some extra compression with these engines, and to hear y'alls advice on which make sense and which will just hurt my engine.

1: Head Gasket
- .73mm Gaskets available XAT, unsafe?
2: Mill to lower deck clearance
- Expensive and not much compression to be gained?
3. Custom Piston heads
- Easiest way to go? Can accommodate boring out?
4. 2UZ crank swap
- The 2UZ crank has a through of 3.31" over the 1UZ's 3.25", would make *A* difference but a noticeable one? Seems fairly cheap at least.
5. Extended connecting rods
- Standard Have a length of 5.7455 (Lextreme) where as aftermarket can go to at least 5.751 (Eagle)

I'd also like to check the numbers I have for calculating compression, cause they don't seem to be adding up to 10:1 like they say should be the stock ratio:

- Bore - 87.5mm
- Stroke - 82.5mm
- Cylinder Head Volume - 43.50cc
- Effective Dome Volume - 8.5cc
- Deck Clearance - 1.25mm
- Compressed Gasket thickness - .325mm

These numbers on Summit give me 9.1:1 CR, so that seems wrong.

Of course I want to do these in association with intake, header, exhaust, cam, and cylinder head upgrades, and maybe even boring out.

Also please let me know it would be better to post this on the Lextreme forum, or even Reddit, I can't really tell where the active users are.