just wondering..i want to go backwards of most people and build an engine that will run on 87 regular and still produce upwards of 300hp at the crank..

i might be limiting myself but on my lg4 the cr is 9.5:1 and i'm running 87, which is recommended in the manual.

would this be ok for a high hp car?

 

If you plan the engine right, then yes, you could have 300hp on 87 octane. Mostly you just have to keep the dynamic compression ratio in check and don't go overboard on the timing.

 

my cars got like 320 at the crank as it sits, can easily run on 87 but I put 89-91 for my own satisfaction and because the motor deserves it lol.

 

i think the compression ration is 10.3 or lower and it's safe to run 87. anything higher it's 89-92 or even higher. have fun

 

Current issue of Hot Rod "Engines" 87 octane 406...490 HP

 

10.3 on 87?? Thats REALLY pushing it...

 

My old motor made 345HP Fly on 87 with 9:3:1 Comp

 

My L69 (9.5:1) liked 87, but I wouldn't go any higher that that for CR unless you have a whopping huge cam.