Electrichead

my car comes factory w/ 9.5:1 CR. can anyone tell me how much hp i will gain ,and if my car can handle 11:1 or higher CR? or will something else splode?

JAWS 021

raising compression = more power but your more likely to ping

lower compressio = less power, but safer with turbo type setup

IF you are sticking NA... raise the compression

Red

What car/engine are you dealing with?

Electrichead

a 2k2 kia spectra 1.8l I4 ..im unsure if its a hyundai engine or kia's own but most likely a kia engine i dont think hyundai put there engines in kias at that time..and what would i do to keep from pinging? higher octane or timing adjustment? most likely im staying NA

[ September 05, 2002, 11:58 AM: Message edited by: Electrichead ]

Red

Higher compression will do very little until you address other points in the engine:

Cylinder head ports
Cylinder head combustion chamber
Valve sizes
Cam shaft profile
Intake manifold
Exhaust manifold

Until you've attacked these first, raising your compression will not do a lot. This goes for any motor, V8's follow the same process as we do.

Electrichead

ok so my process should go

BIM & BBTB
Headers/Full exhaust
Cams
Port/Polish
Pistons

what would be a good CR 11:1 11.5:1 higher/lower?

MaierApril

can these Kia's even handle the higher compression?

MechaniX_034

Uhhhh dude just remember that the higher compression you run the higher RON Fuel you're gonna have to use. Go too high and you're gonna be shelling out the $$$$ for specific race fuels, and that stuff dont come cheap, or very easily.

Electrichead

i figure maybe goin 11:1 because accents and tibs are already at 10:1 i think the kia can handle an extra 1.5 and i dont think id have to go to high with fuel either just raise the octane? to 97 with some octane boost?

MechaniX_034

What fuels are conveniently avalible in your area???