Here is the engine information:

Please solve this internal combustions engine question for efficiency $($net work$/$energy In$).$ The assumptions are that it's an ideal gas, compression and expansion are isentropic$.$ Ratio of specific heats is constant during expansion, compression, and combustion, no pressure drop. combustion is instant.

Use the stoichiometric equation and pv$=$nrt $($and other polytropic equations$)$ and Change in temperature$=$q$/$cv$*$n to find the T$3=$DeltaT$+$T$2.$ Fuel type: Ethanol

Equivalence Ratio: $0\mathrm{.}90$

lower heating value: $11,604$ Btu$/$lb

Ratio of Specific heats:

k$=1\mathrm{.}4$ for compression

k$=1\mathrm{.}39$ for expansion

k$=1\mathrm{.}37$ for compression

Compression Ratio: $9\mathrm{.}0$:$1$

Cylinder displacement: $24$ in$^3$

Exhaust manifold pressure: $14\mathrm{.}7$ psi

Intake manifold pressure: $18\mathrm{.}4$ psi psi

Intake manifold temperature: $600$ degrees Rankine

Intake valve opening: TDC

Intake Valve closing: $4$ in$^3$ BBDC

Exhaust valve opening: $6$ in$^3$ BBDC

Exhaust Valve closing: TDC

Energy release: TDC

With this I attached a similar solved example to show you the method. Take your time and please help