WhitePheonix

A gas station near my home is now selling 110 octane racing fuel for 3.75 a gallon. The TA is in storage now, but once the weather turns and I bring it out I was thinking of filling up the tank with this stuff. I want to know if this is a bad idea and what are some possible disadvantages to doing this. Or if its ok to use the high octane fuel and grab a few extra ponies.

felton316

Just make sure its UNLEADED racing fuel.

Pro Stock John

iTrader: (34)

Well that is most likely 110 leaded.

First of it will slow down a stock engine car. Octane cools things down, so if you don't have a hi compression setup you will have lazy combustion.

Secondly, lead will coat your 02 sensors, they will become sluggish, and they will ultimately stop working. They are expensive.

I am using 110 leaded in my car for dynoing, but my total compression with the blower is more in the 14-15:1 range.

If you did an open loop tune and had some mods, you could try 110, I recall a contact running 36 degrees of WOT timing at the track with 110.

Rogue Leader

anything over 100 octane is gonna be leaded, so unless you have a Denso O2 sensor or a heated O2 sensor, dont bother. It will kill your O2 sensor within the first block of driving, and the stock computer will have a seizure seeing it lol...

samz28

whats so special about the fbody o2 sensor? Isn't it a standard issue bosch 0-1V heated sensor? Like $38 for a generic at autozone.

One tank will not kill it, trust me. I've run on various cars several tanks worth.

Anyways gotta love the white tips

Really fun if you got boost, that 114AV can be

Just buy the 100 octane unleaded and google toluene faq and roll some nasty over 100 like gas.

p.s. octane goes from 0-100, there is no such thing as 101 octane.. There is gas that behaves as 110 octane, but to say 110 octane, well its a scale of 0-100 for regular gasoline. nifty tidbit to remember.

Cummins

iTrader: (2)

i thought the computer didnt register anything over 94 octane? plz correct me if im wrong.

BlackWS602

Exactly what John said. If you don't have the compression to need it, it won't help. It will hurt performance, kill cats, and kill O2 sensors.

samz28

thats why you have ls1edit or equivalent, CRANK that timing up for the octane. or added protection (high octane) can give from unwarranted detonation under the hose. But remember the nitrous fuel jets are designed for a specific gravity of gas, so throwing in 114AV C16 can alter the dynamics of the fueling on the hose

DrkPhx

iTrader: (15)

I ran 2 gallons of 110 leaded at the track and on the way home the SES light came on and sure enought it was the O2's. Cranking up the timing doesn't neccesarily equate to more HP. When I increased my timing from 28 to 30 degrees, I actually lost a couple of hp. If you're worried about detonation on a hot day at the track, mix some octane booster or dd a gallon of unleaded 100 octane gas, but never run 110 leaded on a stock car with O2's and cats.

samz28

definitely won't hurt to tank 1 gallon of toluene or xylene in on those 95F track days when hot lapping.. Better than getting thrown towards the low octane maps.

lead is bad you don't need leaded unless your running some mad compression or mad boost (preferably). Amazing what you can do with some high octane leaded and boost.

JaysGone

chevyzz8 You happen to be correct the stock ECM wont give a tiddly wink about anything over 94 octane. But if it makes you feel faster.........................

Rogue Leader

Adding Toluene or Xylene is NOT the same as running 114 or 105 or whatever race fuel. Those can add a bit in terms of performance but as I said in another thread, if youre looking to get a major incease out of it, forget it, they are like tuning tools.

Toluene and Xylene are used as active ingredients in octane booster, and are essentially 117 Octane dry unleaded fuel, it has similar combustion properties, except it needs some Marvel Mystery Oil for lubrication. 1 or even 2 gallons mixed with unleaded 94 octane fuel will not bring the octane higher than about 99 and wont harm the engine, but you wont really gain much either.

Any race fuel over 100 octane is leaded gasoline, and yes what samz28 said is basicaly right the properties are increased over 100 octane based on the amount of lead and other factors in the mixture.

Finally yes the computer is tuned for 94, thats why I mentioned changing the computer, You arent going to gain a lot by advancing the timing , in fact as was said before you may lose... The only reason we used to use Xylene and Toluene mixes in our Turbobuicks is to keep base timing and prevent knock retard at higher boost levels, the gain was in the boost we could handle not the timing advance.

samz28

i agree completely. But on a hot day when you're hot lapping, and seeing any KR you will lose that KR with a little go go juice in the tank.

Also if your a/f is unusally lean you will find the extra octane will resist detonation a little better but you best keep an eye on egt's regardless.

I don't know much about tuning ls1 (yet), but if you guys say the extra timing from 100 octane doesn't add much, i'll believe ya guys. I come from boost heritage, where extra octane+extra timing = huge gains. Especially when you put the hose on top of the boost Then again the "dynamic" compression ratio of a boosted motor is WAY higher than the (10.1?) of the ls1.

there's a calculator somwhere to roughly estimate boost+static compression = dynamic compression and you'll see why us boost heads need higher octane. It's like 9:1 compression with safe 15psi of boost = 18:1 "equivalent" compression. Obviously it would be hard to run 18:1 n/a (i guess). the joys of boost

hows that turbo buick run? Thats a car one day i wish to have the pleasure of having..

Rogue Leader

Oh I agree that using Xylene or Toluene at the track on a hot day to keep KR down is a GREAT idea on an LS1... You wont gain much but you'll be more consistent and less risk of engine damage.

I come from Boost too, my old TTA used to run 12.83@108 at 19lb of boost on 100 octane and Cooper Cobras, ran 11.99@113 with 21 lbs of boost on C-16 on ET Streets. That was a basically completely stock Turbo V6 exscept for a adjustable wastegate, straight dynomax exhaust,with test pipe and ATR downpipe, chip, intake pipe, tcc lockup switch, and valvesprings. It made 414 HP at the rears like that. I had a 87 Grand National also but it got stolen before I could make a good pass down the track.

I sold the TTA to buy the 99 TA after my daily driver 91 Firebird got smashed by someone in too much of a rush to wait for a traffic light. Plus I got tired of it breaking so often.