More have failed. Not everybody posts when everything happens. I know of more....

 

No one says you are required to bump compression just because you upgrade pistons. In fact, I would prefer to reduce compression. Regarding longevity of aluminum alloys, I guess it would be up to the buyer to make the right choice, eh?

 

The longevity of the piston depends on what aluminum alloy the piston is made from I believe. I think the expansion rates of the alloy used in the piston are what accounts for piston slap. This brings me back to part of my original question. Will upgraded pistons be able to last to 100,000 miles, or are they going to wear out or wear the cylinder wall. It seems that most places are using Ross pistons at this point and Eagle rods as a combination.

 

for the long haul try looking into www.swaintech.com for piston coatings (anti friction) and www.calicocoatings.com for bearings. I have used them with great results in previous projects. The builder makes a differance Build a tighter spec motor versus a loose motor. Ring end gap should be set to the smaller number within the tolerances provided in the service manuel.

 

since we're on the topic..

how long would you guys predict a JUN 2.2L stroked 4G63 to last- running a maximum of 21psi@93octane, not abused, and not driven past 7000/7500 rpm?

the reason i ask is because i am looking to eventually build a strengthened, reliable, and of course torquier motor with Buschur's upgraded 10.5"/20G twin scroll compressor upgrade, ported exhaust manifold, and the onslaught of bolt ons, electronics, and top-end modifications. 450whp on 93 octane with a conservative tune is my ideal goal.

 

If you do not need to upgrade the part beyond stock you shouldn't mess with it, if the stock motor will handle 350whp then don't worry about it. The internals on the 4G63 Evo motor are very strong, if you want to up grade things with out getting into the motor then add a turbo with a full 3-inch exhaust, bigger turbos are less stressful because you can run the same boost and not create as much heat plus push more air. Look at doing a mild turbo upgrade with a full standalone or custom tuned ECU. Run Intercooler and Injector upgrades plus pipes with a solid DV. Get yourself a fuel pump and run with out a Cat if you can that should be enough to get you to 350awhp, I'm at 275awhp with just boost up at 22psi peak, fuel pump, Xflash, I/C, cat delete, 3-inch exhaust and that is on a non dyno-jet dyno.

Do not mess with it if you don't need to, stock parts are best when it comes to long term.
-James

 

You are correct. Required clearances depend largely on the alloy used. High silicon alloys, while more brittle, expand less and therefore require smaller clearances. If piston wear is a concern, talk to your engine builder or contact a piston manufacturer directly and tell them what your goals are. There's no reason an aftermarket piston can't live as long as a factory piston if not at least close. Proper blueprinting of the lower end will also help improve longevity.