mike#9

iTrader: (3)

I am going to be getting a set of stage 2 heads from Absolute Speed. They are 5.3's and I was wondering if 93 octane would be ok?

If not let me know please.

If it is ok... what kind of gas do you guys like Mobil, Chevron, Sonoco...

BergerMan

I've always run Amoco, Mobil or Shell 93 and will continue to do so with my 5.3's. My H/C package should be running in less than a week.

mike#9

iTrader: (3)

You mean... you sell a package?

LS1derfull

You should be ok, i run 11.2 to 1 with my own reworked #241 castings(5.7) with no problems. I have Slowhawk's Edit tuning, and i run 94 Sunoco Ultra, but i have also ran Mobil 93 with no knock issues.

highgmc

should be fine

CamM

11.2:1 compression with 93 octane and Texas upper 90s degree heat with no problems here.

Buckshot

Should be no problem. I run Chevron 93 with my 11.3:1 5.3l heads with zero problems.

98TAauto

iTrader: (2)

93 here and doing fine. Its all in the tune and just the gas in your area. I have one edit file with a little more timing to help driveabilty around down and I got slight ping in the 1500-2500 range but that was only after I put city gas in my car. not sure if the gas there was bad or not. Im running 29-30degrees of timing at WOT with no issues though

some gas just sucks though cause its water and crap in it

mike#9

iTrader: (3)

I am out here in central Florida, and it was 97 degrees yesterday, and I think 130,000 % humidity!!

so 93 should be ok... or it will definitely be ok.

We have Chevron, Mobil, Amoco, all the major playas in the gas industry.

Hope everything works out.

Also... about 8 months ago a Sunoco was put in... does every station have the 94 stuff... and how is there 93 octane (do they have that?)

Taspeed

iTrader: (1)

ok..i'm running the 5.3's and F1 cam...no tuning. I'm closer to the 11.5 mark and on really hot days with the ac running it will ping a bit on the interstate. 93 octane here and no major problems here. I think with tuning you would be fine...its all in the timing.

98_1LE

iTrader: (17)

A lot of it depends on what cam you are running. Bigger cams typically allow more compression.

mike#9

iTrader: (3)

Which means what.... I would have to run higher octane than that.

Or is it that since it is a bigger cam (will be 230/236 .592/.605 112 lsa) It will allow me to run 93 will less worries?

99 Black Bird T/A

iTrader: (4)

Very true. Stock cam with stock heads my car would show a KR on the top end with 93. The car would ping on the dyno etc. With more compression ie ~11 to 1 compression & 224 cam using 93 KR was like .1 and no audible ping etc.

Taspeed

iTrader: (1)

it really depends on a lot of things...timing, duration, lobe separation, and overlap of the valves. Its really hard to predict predetenation in an engine. I said it once and will say it again...its all in the timing...and a little a/f ratio's. If you can use LS1 edit you have the ability to keep it from pinging, but you have to remember that by removing timing you will sacrafice a little hp. Usually not more than a few. you can also adjust the a/f ratio's..just richen it up a bit....So in retrospect everyone here is right in some way. The best thing to do it pick the cam you like and tune it. It will run without pinging on pump gas!

OSoSlow

What about with Californias 91 octane?

Fireball

iTrader: (21)

.040 off my 5.3L heads. Run 93 octane with no issues

Reboot

iTrader: (5)

I'm running 11:1 and 27 degrees of timing on 91 octane without any issues.

99 Black Bird T/A

iTrader: (4)

Have 11 to 1 with 5.3 heads, run 93 all the time. Car's never shown more than .1 degree of KR. Should work fine with a decent cam. 11 to 1 with a stock cam might not work too well. My car would ping with the stock cam & stock heads at high rpm.