Higher compression to gas mileage and power (?)

Is it the 1.8 rods with the 2.0 pistons that raise compression, or is it the 2.0 rods with the 1.8 pistons that raise the compression.


I heard that higher compression engines run more efficiently if there is adequate cooling and I was just wondering what it would take.

Here in cali we have **** for gas 91 octane rating, do you think it would be safe to run an 11.5:1 CR or somewhere in the ballpark with 91 octane?

If the piston/rod combo raises it to 11:1 shouldn't shaving a bit off the head achieve closer to an 11.5:1 without clearance issues?

I have read that on a stock engine at 11:1 it should net around 4-5 horses, but with it somewhere around 11.5:1 and a cleaned up mildly ported head and some odds and ends, shouldn't it achieve around 15-25 horses with a pretty mild tune?

Odds and ends are like ported throttle body and port matched intake manifold.



Just throwing this out there, because I am just wondering why people rarely point out the efficiency increase and better fuel economy provided by a higher compression motor.

Been thinking about it, and everything should cost a little over a grand.

I need the fuel economy, but I also want more power.


Would it be worth it to run a good sized turbo with the stock compression to retain fuel economy and gain power. Maybe get a turbo with an assload of lag, like an old 1990's HKS turbo or something so you will be out of boost until like 4000 rpm.

A lot of guys seem to have problems rigging up their turbo setups and they seem to cost more than anticipated for them, so I thought that this NA setup should be more predictable and easier.

I've looked around and have searched a lot on the forum, and I just needed some clarification on some things.