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Yes - that's what they looked like. I've seen later model turbo pistons with larger dishes and less of a ring, but these were fairly thick. You would probably want something more like your picture, however, although I don't think the squish/quench area around the spark plug does much. You wouldn't need dished pistons at all, of course, unless you either have an unusual head like mine (very small chambers) or you are going for an abnormally low compression ratio - to use boost on later on. The dished pistons allow you to get some squish and still meet your CR goals.
The jury still seems to be out on the advisability of running boost on an overbored B20 - and I must agreee. Makes sense to get some more cc's on a N/A engine, but on a boosted engine it is probably a better idea to leave the block thick and strong, and just turn the boost up a little more.
After a few shakedown problems(*) the PV is feeling quite peppy. It now has about 110 miles on the new motor - due for its first oil change. I'm still holding the revs under 5000 for a while longer, but you can really feel the Isky VV-81 come alive as the revs hit 3700+. It feels quite strong on the highway in 4th and OD - just leaps ahead. I think it pulls about as hard in 4th gear now as it used to with the original tired B18 in 1st gear. I'd probably have more low/mid range torque with a more modern cam profile.
*: - Valve cover gasket keeps popping out - there isn't much to hold it in place between the aluminum rocker bridge and the aluminum valve cover. Permatex gray applied to a meticulously scrubbed and oil free rubber gasket and valve cover seems to come apart as soon as it sees oil - I think it breaks loose when I tighten the cover on and the rubber squirms and flexes slightly. I'm about to try gluing a harder, less squirmy cork gasket on it with something a little stronger if it doesn't stop giving me trouble.
- *argh* A wire popped off the 4th gear switch on the OD - leaving me stuck in 4th on the freeway - the transmission tunnel is so darn tight on the PV that I had to unbolt the crossmember and drop the trans down, and work with long needle nose pliers theough the shifter hole like a surgeon doing orthoscopy). The multimeter showed 12 volts at the connector in the engine bay, and 0 at the solenoid, so I knew something was amiss with it and yes - one of the connectors was off and loose - I must have bumped it putting the motor back in.
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I'm JohnMc, and I approved this message.
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