TA Collector

iTrader: (1)

This may or may not be a dumb question but need some answers. My LS1 is built, pump gas, 500+ flywheel hp motor, and am wondering if there is any advantage to putting 110 octane in it, or will that gas possibly melt down my o2 sensors due to more heat overall everywhere? Will this also affect the ecu tune done to it as well? Is there any power/performance to be gained by doing this? Appreciate any feedback possible, thanks.

TooLateVTEC

iTrader: (2)

If its built to run on pump gas than it wont gain anything just by dumping 110 in it except kill the cats and probably the 02's.

In order to take advantage of the higher octane, you would need to add timing or more compression.

Not worth it.

Ive got 6 gallons of 112 left over from last racing season and if I knew it wouldnt kill the o2's and cats I wouldve already ran it through my car.

garygnu

you can buy hi-octane unleaded,good if you run NOS.

LS1MCSS

iTrader: (18)

If you are going to dump anything in it that's higher octane, get 100 octane unleaded.

SweetS10V8

iTrader: (4)

Does your car need more octane?

TA Collector

iTrader: (1)

Probably not, I was considering experimenting with it if it would yield any better results (not that I'm unhappy with it now). Like anyone else, just looking for gains anywhere I can at cheaper costs. Thanks for all of your guys' input so far.

bww3588

iTrader: (49)

as unbelieaveable as it might sound, right before i put LT's and TD's on my car, i ran it on 93, then dumped 5 gallons of 110 in it right before i made 3 more runs, and as the 110 got in the system, it picked up 3mph in the 1/4. this was basically stock car. i didnt care if it killed the cats or O2's because i was ditching the cats and getting new O2's.

02 BLK WS6

iTrader: (11)

110 leaded race gas will kill your O2 sensors quickly. You also need a tune for race gas.

SweetS10V8

iTrader: (4)

Race gas makes ZERO power over pump gas. It has no more BTU content to make more power. It only resists detination by being harder to ignite.

bww3588

iTrader: (49)

i dont quite beleive this...

for one reason, and its real world....

i had my dad's 402 BBC on the dyno at school, (the same place the jegs engine masters is held every year) and we tuned it and timed it to run on 93, then switched the fuel to 110 CAM2, changed nothing else, same 30* total timing, same jets same everything back to back dyno runs, and just the switch in fuel gave us 15 more HP average over 3 runs.

then we gave it 6* more timing and picked up another good bit of power...

blackLS1m6

iTrader: (14)

Sweets10v8 is right, you wont pick up any power by simply switching to race gas. You will either make the same power or possibly less from an incomplete burn.

bww3588

iTrader: (49)

no offense, but your telling me the dyno lied?

back to back runs within 10 minutes of eachother


3 runs with 93

then 3 runs with 110 and 15 horse just came out of the woodwork?

bww3588

iTrader: (49)

i realize the chemical and paper reasoning behind this, but you cant argue with what happens when it all comes together.

blackLS1m6

iTrader: (14)

Nope never said your dyno lied. What is the compression ratio on your dad's 402?? Is it high enough that it might detonate on pump gas???

blackLS1m6

iTrader: (14)

Matter of fact ive had a few big block chevys myself and have run each one at the track. I have also used 93 and switched to 110 octane with no gains in MPH and identical ets.

bww3588

iTrader: (49)

it was a 10:1 engine, aluminum heads. it ran fine on pump gas, no detonation or spark knock.

01'SSLSX

this is Correct

01'SSLSX

if this was true, then lets say i take a 4 cylinder that runs on 89 octane and then go ad 93 octane, it will make more power?? i dont think so!

some fuels are more knock-resistant than others. thats why we have octane ratings. Octane rating does not relate to the energy content of the fuel (see heating value). It is only a measure of the fuel's tendency to burn in a controlled manner, rather than exploding in an uncontrolled manner.Since higher octane fuels have higher activation energies, it is less likely that a given compression will cause autoignition.

It might seem odd that fuels with higher octane ratings are used in more powerful engines, since such fuels ignite less easily. However, an uncontrolled ignition is not desired in an internal combustion engine. The fuel must be fired at a precise time. An ignition too early will cause detonation.

A fuel with a higher octane rating can be run at a higher compression ratio without causing detonation. also more timing is aloud for its slow burning characteristics.

A common misconception is that power output or fuel mileage can be improved by burning higher octane fuel than a particular engine was designed for.
Since switching to a higher octane fuel does not add any more hydrocarbon content or oxygen, the engine cannot produce more power.

the engine and tune have to be set up for a specific octane to BEGIN with, simply switching octane levels effects nothing

SweetS10V8

iTrader: (4)

Very possible... Or operator error, or you were knocking and need more octane from the begining.

You need to make about three runs, make sure they overlay well and then average them all together to get one set of data. Then swap parts and do three more runs. Throwing out any high or low flyers along the way, and theres a few runs in every session that just arent good data..

Best case senario, you reinstall the original part and rebaseline for the most accurate and beliveable results....

bww3588

iTrader: (49)

read my posts, we made 3 back to back runs with 93 then 3 back to back with 110. averaged them all and picked up ~15 hp.