will the addition of a cai and a tune with xcalII shorten the engine life, i just switched from the 87 cct. to 93 oct. tune but i may switch back in the future, does this cause excessive stress on the engine. I love the way my car performs with the tunes but i donot want to hurt its life.

 

my opinion is that it already has already been tuned at the factory to run on 87.....chances of tuning it for a higher octane should not hurt. It's how you drive after the tune that could hurt it

 

I agree. What you need to keep in mind, though, is AT ALL COSTS try to prevent detonation. That will surely raise the potential for engine failure. Let's say you decide to switch back to the 87 octane program and don't like the reduced performance level. So you re-tune to 93 octane BUT you still have a full tank of 87 - BAD, BAD, BAD. Make sure you use up all the 87 to the empty red-line, fill up with 93 octane, THEN re-tune to the 93 octane program. Just remember that and you can ignore the rest of this post, but if you're interested:

Detonation is definitely not cool. Detonation causes sudden pressure changes in the cylinder, and extreme temperature spikes that can be very damaging on engine pistons, rings, rods, gaskets, bearings, and even the cylinder heads. Even the best engine components cannot withstand severe detonation for more than a few seconds at a time. More severe detonation obviously leads to more severe forms of engine damage. If there is enough heat and pressure in the combustion chamber, detonation can begin to occur before the spark plug even fires, which would normally initiate the combustion. Under these circumstances, known as "pre-ignition", the piston may be travelling up towards a wave of compressed, exploding gas. These are the worst kinds of detonation conditions, and can bend connnecting rods and destroy pistons.

John