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[Rius]

Stie cineva ceva....o legatura ...sau cum as putea determina ce compresie ar trebui sa aiba un motor cu un raport de comprimare de 13,3:1 ?

Formul magica compresia= 1.55xE - 2.35 unde E = raportul de comprimare ...e un mare fas


Contra exemple : nissan gtr: raport comprimare 9.0:1 compresia standard 9.7 bar / 300 rpm
nissan 370z: raport comprimare 11:1 compresia standard 16.7 - 23.5 bar / 300rpm
nissan 350z: raport comprimare 10.6:1 compresia standard 12.75 bar / 300rpm


Oriunde din exemplele de mai sus ai folosi formula ..nu iese

[BSH]

An equation I use for estimating cranking pressure from static compression ratio (CR) for engines in good condition with standard road cams is as follows.

Cranking pressure (psi) = CR^1.3 x 14.7 x 2/3

CR^1.3 is the Compression Ratio raised to the power 1.3. On pocket calculators you can do this with the x to the y function.

For modified engines, or more specifically engines with long duration cams you need to then apply the following approximate factors.

Fast road cam - multiply by 0.95

Rally cam - multiply by 0.90

Full race cam - multiply by 0.85

Example. A rally engine with 11:1 static compression ratio.

11^1.3 = 22.58

22.58 x 14.7 x 2/3 x 0.90 = 199 psi


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Asta am gasit eu, sper sa fie de folos