all the trims and boost cuts in the world wont save everyone.

example.. I had a kid with a turbo honda, it made good power, etc..

he calls me up 3 weeks later talking about its blown up and all last week it was missing and wouldnt go past 6000 rpms at wot... Turns out he changed the vac lines going to the wastegate, melted one in 1/2 and was driving around for 2 weeks holding it on the boost cut and melted a piston.. not saying lower compression would have helped b/c i have never tried this but you get the idea.. lol

I have had kids change cams and intake manifolds, turbo's, you name it, then wonder why their car blew up, or drive to a state where there is only 91 octane and blow their stuff up, its crazy

 

Oh i understand. I try and spend a ton of time educating them to keep this from happening. I tell them, if it doesnt run PERFECT, every day, every time you drive, you call me.
If its my deal, ill fix it. If its your deal ill show you what you did wrong.
The FWD kids are VERY hard headed and so i dont build many of them anymore.

 

With these pistons you can still get quench, and combustion chambers with flat top pistons almost always have better burn characteristics anyways.

While true that when not under boost your loosing some overall thermal efficiency of the engine, in almost every actual case I have seen, people don't usually loose gas mileage but get almost the same or better due to a better after market tune vs the tune from the factory.

Around here I know that some gas station routinely put regular in their premium tanks. I don't trust pump gas whatsoever, I would always take lower compression for a street car.

Although suggested by the definition, dynamic compression isn't the exact compression experienced by the engine over all operating loads and RPMs. It's merely a number to make overall judgments on the tune of an engine, just like the static compression. Different combustion chambers have different burn attributes and respond differently to compression. So theres no universal compression numbers to go by--although there are pretty good models we still establish the proper compression through empirical evidence for the most part.

When an engine is tuned properly the finite wave interaction between the intake and exhaust can actually bring the pressure in that combustion chamber for a naturally aspirated engine above atmospheric pressures, thats how volumetric efficiencies of greater then 100% are reached without forced induction--This absolutely suggest that "dynamic compression" isn't the actual compression numbers under those conditions.