Will High octane make much of a difference??

[Civic Jim]

Every time i go to fill up i see the high octane fuel and wondering if it will make much difference, I have been told by some people that it burns out the valves, but do you think it would be OK to run my D16A9 on it and would I get better performance with it

any help welcome

Cheerz

[crxlvr]

you wouldnt see much of a performance in a low modded car, but it will give you something, plus it has higher anit-knock additives for when you run boost or high rpm applications.

[Tony]

yea, it will make a little bit of difference. Don't know really if its better for the engine or not, but I run 91-93 Octane whenever I can.

[darolh]

If your engine is not knocking it will make no difference and do no harm....except to your wallet. I actually backed off the spark in my car a bit cause I get a tiny little bit of knocking in warm weather. If I climb over the pass in warm weather I put medium grade in so it doesn't ping.

1st: Check your timing. If it's correct and you're pinging either go to higher octane gas or back off the timing a bit. It's your choice. You'll lose a little poop by backing off the timing.

[mellowboy]

Yeh doesn't make any bid difference. I put 100 octane on my car and still the same shit. Its harder to get my car started at first cause of the high octane but then the second crank it starts up fine. Its good for your engine either way if u use 91-94 octane.

[Redrum240sx]

high octane and octane booster can help your cars hp if your car is heavily modified if you run an octane that is to high for your car you could actually lose hp

[Melt]

Originally posted by JDMB16 @ illusiverides.com
ok, don't use 93 octane man, Civics don't need it. Higher octane fuel without major mods like higher compression pistons, turbo, n2o, SC etc. will make your car run rich hurting performance. Stick with 87. And also, you won't actually get more power, with major mods as listed above, you can get detonation hence the reason why we would retard the ignition timing and use a higher octane fuel.

[dfarres]

I only have a DX with a few mods but when I switched from 89 to 91 I noticed a little more pick-up when passing & my mpg went from 33 to 35. Every couple months I put a gallon of MTBE & cleaner in with a full tank & it just gives me a little refresher & a few more mpg's.

[red4thgencivic]

Higher octane fuel burns slower than regular fuel, that's the only difference, the octane level is just a rating of how much the fuel has been processed. Kinda like a rating of how pure it is.

The only reason you would need high octane fuel is if you have very high compression something like 11.5:1 or higher. THis high compression results from mods such as turbo, n2o, and things of that sort, if you're having problems with valves knocking or anything it's probably just your timing.

[mellowboy]

It's not necessarily slower as much as it is cooler. Supposedly the higher octane you use, the cooler the burn is. That's why when you start doing performance upgrades, people recommend going at least with a 91/92 octane fuel to aid in the prevention of detonation(knocking or pinging).

[plkelley]

Originally posted by red4thgencivic
Higher octane fuel burns slower than regular fuel, that's the only difference, the octane level is just a rating of how much the fuel has been processed. Kinda like a rating of how pure it is.

Thats not right. The octane rating tells you how much the fuel can be compressed before it spontaneously cumbusts. Pinging is caused when the fuel ignites before the spark fires, Its called pre-ignition. The reason they recomend higher octane when you start to modify is because usually one of the thing people do when modding is raise the compression or ad some type of forced induction which causes higher compression.

Therefore...if your car doesnt need it then you will most likely see no gain in performance. Those of you who do see a performance between low octane and high is because most gas companies water down the low octane to make more money.

[kris]

:o I will need it when my motor is finished.

[mellowboy]

Originally posted by kris
:o I will need it when my motor is finished.

How high u gonna get? The compression!

[kris]

Originally posted by mellowboy


How high u gonna get? The compression!

Guesstimate is around 12.5:1

[mellowboy]

Yeh i'm gonna be doin the same except on a b-series. I sold my d16a6 to my friend and he got arias 11:5:1 compression with crower rods. Hes gonna do the head soon. He got an upgraded clutch act. that shit pulls hard man. Just imagine fully built...