puting SOHC pistons in a DOHC block will raise compression. so logicaly putting DOHC pistons in a SOHC block will lower it. would this be a good idea when turboing a KA? with the low compression ratio it would make less power but be more reliable, no?
why would you want to turbo an E motor ?
really, i dont. just wondering.
There’s nothing wrong with turbo’ing a SOHC motor as it is (providing it has good compression numbers and is in decent shape).
However, I wouldn’t bother changing to DOHC pistons. I’d say leave it as it is for lower boost levels, or rebuild with forged pistons/rods etc for higher boost.
There are much more important factors to a KA-T’s reliability than that, such as proper and careful installation of parts, good clutch and braking systems, good & clean motor oil, gasoline octane & timing, your fuel system and/or tuning, using a good & preferably new turbo, good manifold, and what not else.
Have a look around the SOHC KA-T section on http://www.ka-t.org for some more good info.
Cheers.