PDA

View Full Version : What octane are you running, fellow '84 owners?



craig0ry
03-29-04, 01:52 AM
Just curious - the 'vette says "premium recommended" but I was running her off of 87 and I did not hear any pinging or knocking. I ran the tank down pretty low and filled her with premium (36 bucks worth to be precise! Ouch!) and I did not notice any improved performance. Does the '84 even have the ability to detect knock and advance or retard timing to take advantage of the fuel octane?

Bone stock engine, but 136k miles. You'd think the carbon buildup would have raised the compression but she didn't seem to knock at all before.

So what are you guys using?

RichHeald
03-29-04, 05:25 AM
At Carlisle 2003, C4 expert Gordon Killebrew (gordonkillebrew.com) told our seminar class that if the engine wasn`t knocking or pinging, then running the 87 octane would be OK. He said that the electronic engine management systems were designed to compensate for the lower octane. I usually run 93 octane (at least 89) in my Ruby, and believe that I get better mileage with a higher octane.

corvetterider84
03-29-04, 09:35 AM
So what are you guys using?
I've been running 87 octane in my 84 since I got it last August. I've never noticed any pinging or engine knocking whatsoever. I do believe I ran 93 octane a few times and did notice a slight increase in gas mileage, but with the prices of gas today I'll stick with 87 octane. Just my 2cents.

82ColEd
03-29-04, 12:42 PM
I've ran a few tests and am currently running 87, but: I seem to notice a slight decrease in acceleration (both with my test car, a z28 and the vette). So, my planis, once the 87 is gone, i'll put 93 back in like i used to. I dont drive it daily, so the gas price isnt my first concern. 87 doesnt seem to bother my 82 though.
And i believe we have the same engine (82CE vs. the 84), the cross fire 350, in our cars, so i figured you wouldnt mind me replying.. ;)
STefan
:w

tnovot
03-29-04, 08:50 PM
Just curious - the 'vette says "premium recommended" but I was running her off of 87 and I did not hear any pinging or knocking. I ran the tank down pretty low and filled her with premium (36 bucks worth to be precise! Ouch!) and I did not notice any improved performance. Does the '84 even have the ability to detect knock and advance or retard timing to take advantage of the fuel octane?

So what are you guys using?
I generally try to use 89 octane. Have used 87 with no apparent problems but don't really drive it hard enough to see any difference. I buy octane boost when on sale and usually use it if I get 87 octane.

craig0ry
03-29-04, 09:18 PM
I generally try to use 89 octane. Have used 87 with no apparent problems but don't really drive it hard enough to see any difference. I buy octane boost when on sale and usually use it if I get 87 octane.
Yeah, what I was trying to figure out is if the engine can adjust the timing to take advantage of the octane level. If this is so I was going to split the cost of a 55 gallon drum of Toulene with my buddy. This way I could run a consistent 100 octane. An unnecessary expense, I now think.


...At least until down the road when I have the money and I figure out how to rig a blower or run a 75 shot on this crossfire injection. :X