Flat top pistons
I noticed that the 2.8l flat top piston swap is addressed, but seemingly never been tried.
When i rebuilt the 2.9l at 215k i swapped the 2.8l pistons into the 2.9l. It was VERY complicated to figure out if they would actually work, lots of measurements and math, (how far a rod stretches at high rpm?!) but it is possible with a few modifications.
so, The Tech:
I bored my 2.9l .025 over, and used STL-433NP20 sealed power flat top pistons, with chromoly rings.
The piston skirts on the 2.8l pistons are longer than the 2.9l pistons, so approximately .030 will need to be shaved off the crankshaft counter balance weights.
The Effect:
Running a stock replacement cam, high volume oil pump, 16lb injectors, full intake port and polish and flat top pistons.
Definite power increase, NO drop in low end power and it will pull all the way to redline even on 87 octane gas.
The Conclusion:
Its everything you could want for a performance increase on a budget, it worked for me, and even passed CA smog.