Engine Selection

[Twistchi]

I am currently working on a 84 cutlass supreme brougham and the time has come to find a powerplant. The original 307 4v is long gone.

I need to strike a balance between power and economy.

What are some good ways of increasing power AND fuel economy at the same time. I only know of one and that is increasing your compression ratio.

[techinspector1]

Currently available pump gas limits the compression ratio you can run without detonation. About 9:1 with iron heads and 10:1 with aluminum heads is considered the optimum today.

This equates to somewhere around 170 psi cranking pressure. You may be able to run a little higher than that with a good, tight squish and piston/chamber massaged to eliminate hot spots.

[chappy_692000]

porting the heads will also give you what you are after by letting it breath it will effectively increase hp