bigL

iTrader: (3)

Im taking her to the track tonight and would like to buy some race fuel to maybe get a little extra kick.Does anyone have an octane suggestion or any advise.I have used race fuel in other cars but never in bigL.Thanks

Burton

What do you have done. If it is mostly stock I would run 104 unleaded.

Ben

EDIT

This may help also

http://www.vpracingfuels.com/vp_01_fuels.html

bigL

iTrader: (3)

I have an Srt intake full exhaust including S&S headers TC,valve body,3;76 lsd and all the suspension goodies.

Burton

Yah I wouldent use anything over 104 unless you have some sort of fuel tuning device to lean the car out.

Ben

bigL

iTrader: (3)

Thanks.What Ive done in the past is 1/4 tank of 94 and 1/4 tank of 110.Ive never done this in my GS but may have to if I cant find 104.Thanks for the info.I'll post times early next week.

LBC

Your car doesn't need that level of gas. 91-94 octane is fine. It will go slower with anything higher.

bigL

iTrader: (3)

How so??????

LBC

well, the lexus computer was tuned to run on 91-94 octane. the mods you have would hardly cause any detonation that would need the level of increase for higher octane.
higher octane just burns slower and is harder to ignite. so without any addition timing increase or ignition system upgrades it would just be a waste of money, and energy in the engine.

bigL

iTrader: (3)

I can see the computer part but Im pretty sure higher octane will ignite faster and burn faster.

Lexmex

We sell 100+ octanes at our track here in Mexico City, all leaded. It really won't have any effect in a vehicle unless two things, the gas is poured in when the tank light is on or as we recommend, completely empty.

Second, we tell people to check their timing as I have seen on repeat occasion people just fill the stuff up, go to the track and get maybe .1 benefit at the most in the 1/4 mile. From our experience, the leaded gas won't immediately hurt the catalytic converters on just one tank, and one of the benefits is better valve seating, but the goal is to go faster.

LBC

nope, higher octane burns slower to help with knock and cool down the cylinders before ignite.

87 burns the fastest and hottest, thats why it causes "knock" is so many cars.


you'll go slower, stick to premium pump gas.

LBC

100-104 sunoco or vp or torco is all unleaded.

leaded will not clog the cat up, but it will very easily kill an 02 sensor, and quickly and foul plugs out.

Lexmex

Sunoco is the one we sell (since Pemex is crap). We haven't had anyone report a problem with their cat or O2 sensors, but a few people who work on their vehicles said their O2 sensors were a little whiter.

If you run leaded enough time of course that cat is going to say meow, as it doesn't have nine lives.

LBC

sunoco 100 and 104 is unleaded.

Lexmex

Oh, I was referring to the 110 to 116 range.