can you use reg unleaded in new 06 civic si?
 

Can you use regular unleaded in the new Si??

i think it recommends premium

I know it recommends that, but I don't want to use premium, $$$$$$$$
so, is it cool to use regular unleaded is what I am asking, is it safe for your civic??

no it is not safe, run what the manual says and stop complaining!

you can but your gonna have a lot of engine problems...because of the high compression (11.1:1 i beleive) you need a higher octane gas which is harder to burn...when compression gets to higher levels there is a lot more heat produced and with lower octane gas which is meant for easy combustion (the higher the octane the harder to burn) will cause it to pre-ignite or pre-detonate because of the heat...(funny how we pay more for gas thats harder to burn) thats the main reason why diesel engines dont need spark plugs because they are at tremendously high compressions but the rpms only go up to 4000 or so

you can only use 87 on an engine lower than 10:1

i am not complaining
 

I don't have one yet, but I have one on reserve, if I have to run premium gas, forget it, too much money pissed away, gas is a rip off as it is.......a fool like you can burn premium if you want and you have the $ to burn...I don't

running high quality gas is a price you pay for a high performance car. i will also tell you that if you hate high gas prices call your local airport and ask them how much 100 low lead is, its about 3.70 a gal here

simple conclusion.. if u dont wanna buy premium, dont buy an SI.

its only a couple dollars more everytime you fill up. there isn't much difference between reg/prem when you're paying 20k for a car.

but its not a sports car. Its still a honda civic. yeah its faster than a normal civic but its a 20k car. it should be able to run 87.

^^
no. Like the RSX type S. You must use at least Premium unleaded 91 octane. You WILL run into engine problems if you dont. And yes, the Civic Si IS a sports car. In the regular civics you can use regular unleaded 87. However with the Si MUST use at least 91 octane. The compression is very high.

If you use 87 it'll knock like crazy hell.
If you use 89 it'll run, but run like crap.
If you use 91 or more like it says, the car will run happy and last a while.
Its a 14ish gallon tank. So its less than 3 bucks a tank. You're buying a 21K car that still gets 30MPG. Do the math. If you can't afford the gas, don't bother with the car. Leave it for someone who's gonna take care of it.

thanks ya'll...keep info coming

most higher performance cars require 91 and up.... I would assume ppl who can afford to pay off an Si in full can afford gas for it.... the gas milleage isnt horrible on it anyhow..... but if you cant pay up, dont play the game.

simple and short ^^^ read this over and over again..
everyone that has posted is telling the truth and on the dot. The engine require the octance because of the compressions, so give the engine what it wants.

thanks , I really appreciate this ya'll, the dealer here would never even mention this, I thought of it (as I thought of my payments for the si!- my civic is paid off that I have now!), so, I put a $500 deposit down, which is refundable, but I may have to get my $ back. I love how my civic takes reg unleaded and gets 40 mpg on highway trips!

:tup:

thanks...I am decided...keeping my civic...not buying an Si.....for now