Octane boost?

[wang wang wang]

i just put SOHC pistons on my DOHCand i was wondering if i always have to put octane boost or its ok to run it?oh and i scanned my car today.(Codes)crank position sensor&knock sennsor back 1.Any tips on fixing these?...thank for looking

[Guappone240]

Replace the sensors

[marlin29311]

Octane booster does nothing - it only raises your octane by a fraction per bottle...just buy better gas.

[480sx]

So, you put SOHC pistons in your DOHC, raising your compression to roughly 11:1. Do a compression check and figure out what PSI your at per cylinder out of curiosity.

You have yourself there a detonation cannon. Run the best gas always and i wouldnt stomp on it until you get it tuned. I doubt you guys have access to E85 or any cheap race gas so your kinda sol.

Idk why you did that dude, you shoulda done research. You kinda screwed yourself lol. First off, without a tune the extra compression ratio isnt going to be utilized, so your not really going to see many gains. In addition, that knock sensor code might be the only thing stopping your motor from blowing. Have you done any wide open runs with it yet?
Modified by 480sx at 7:38 PM 6/3/2009

[liquid_cool]

angry hippy is rite man..you need to do a few things if you wana keep it this way.....get a safc..or emanage..allso bigger injectors..you are going to need more controlled fuel to battle the ever present possibility of detonation...i myself run 11.3:1 cr and dont have any issues with just using super...untill you can controll your mixture better..i sugest retarding the timing a little allso ..so you run a tad rich.

[Seishuku]

With higher compression, timing is way more important than fueling and rich mixtures only go so far to prevent knocking.

11:1 isn't really that high, most NA engines these days are 10.5:1, it's not that far off.

Bumping back static timing 5 degrees is actually probably too much, but is ok for safety sake. It's not doing anything for performance though.

12:1 or more would be pushing it for 93 octane though.

[wang wang wang]

k thanks for the tips guys