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what is engine limits ?!

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salaam to All ,

Is there a method to know the limit of a particular engine when for example boost added to NA engine ?

website or database anything ?

or should i damaged few engines to reach such information !.

Unfortunately there isn't. With popular engines you can usually research what others have achieved with them and get an idea of the safe limits. Other than that it is often down to experimentation. You also need to understand that the power level that may be safe for a few dyno pulls may prove to be excessive for a dedicated race car so it's very application dependent.

As Andre implied, it will depend on the engine - some may be very tolerant of massive increases, like some Honda engines, but some may be stressed by 5psi boost. There is also the question of how well the tuning process is done on each - a bad tune can kill a NA engine but a careful tune may allow that same engine to survive quite high levels of boost.

What engine(s) do you have in mind, as most already have people playing with them and finding their limits. Sometimes the weakness(es) are something quite different from what might be expected - for instance, one engine I'm familiar with has a factory ignition cut at 6k8 rpm and is fitted from the factory with notoriously weal big end bolts that have been known to fail at even that low rpm - but with ARP, or similar, replacement bolts the engine has been taken as high as 8k5 by some, although over 8k is generally thought of as the 'safe' limit. Some other engines may have conecting rods with insufficient compressive strength, some may have pistons that aren't up to the additional loads and temperatures that will be applied - every engine has weaknesses, it's just a question of what is reached first, for the modifications made.

Don't forget the rest of the supporting systems - fuel system capable of the required flow AND pressure, cooling (oil and water), clutch capable of the increased torque, etc - different manufacturers are going to have different levels of 'reserve' and that has to be born in mind.