Race gas questions?!?!?

[mattlqx]

Yeah I'm curious also why do so many people dyno on 91? 93 hard to find?

Come visit out west sometime, it's a whole other world.

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[TheDeadCow]

I'll just leave this here
http://www.pure-gas.org

 

[jwhite]

It took me seemingly forever to explain this to a co-worker! He couldn't get that 87 is more so combustible and the pre detonation power loss and possibility of burning a piston than 93 octane. He was putting 87+an additive of toluene in his Saleen Mustang. The pre detonation was awful! My 350 loves the 100 stuff

 

[krt22]

If the car could gain power with higher octane , it would have to be tested for that extra power. The gt350 also has a warranty , you cant just make as much power as you want. I read on another forum that they believe the knock sensors have to compensate for the added vibration of the 5.2 so that could explain the hp gains with race gas.

its also possible that going from 91-93 would gain that same hp or close.

You are offering nothing but pure conjecture at this time. As others have posted, some have done back to back dyno runs with 91/93 and 98-100 and saw a definite power boost. No one made any claims of "making as much power as you want", just that there is a little extra room within the stock tune

The stock ECU has thresholds of how much it will advance the timing based on how much knock its detecting, IATs, cylinder head temp, etc. So it appears that the max timing of the stock tune does not occur using 91 or 93, so there is more left to advance if you can reduce the knock threshold.

 

[RonnieSVT]

You are offering nothing but pure conjecture at this time. As others have posted, some have done back to back dyno runs with 91/93 and 98-100 and saw a definite power boost. No one made any claims of "making as much power as you want", just that there is a little extra room within the stock tune

The stock ECU has thresholds of how much it will advance the timing based on how much knock its detecting, IATs, cylinder head temp, etc. So it appears that the max timing of the stock tune does not occur using 91 or 93, so there is more left to advance if you can reduce the knock threshold.

I worked at a shop with a dyno jet in the 90s
It was typical to go to a track and see older Vette guys running 100 octane n stock cars and not running any faster. I have never seen any stock car make more power with race gas but maybe the 5.2 is the exception.

I saw the 98 octane post and they claim a gain 30 ft pounds torque ! Lol

 

[ITLRUN]

** I have not read through the entire thread and this may have already been mentioned.

These cars have knock sensors that detect detonation. The computer is also always monitoring many sensors and making adjustments based off real time data. These cars make more HP with 93 octane than they do with 91 octane because of the computers ability to add timing in the absence of detonation. 100 octane fuel would allow the computer to add even more timing resulting in even more power. It's a pretty simple concept.

 

[RonnieSVT]

** I have not read through the entire thread and this may have already been mentioned.

These cars have knock sensors that detect detonation. The computer is also always monitoring many sensors and making adjustments based off real time data. These cars make more HP with 93 octane than they do with 91 octane because of the computers ability to add timing in the absence of detonation. 100 octane fuel would allow the computer to add even more timing resulting in even more power. It's a pretty simple concept.

So your saying any car is going to make more power with 100 octane?
Its not that simple!

Most performance cars are tuned to make max power on 93 octane and running 100 wont to anything , but whatever !

If 100 octane truly makes more power that would mean that on 93 octane that the ecu is already pulling timing from the factory on a stock car.

 

[ITLRUN]

So your saying any car is going to make more power with 100 octane?
Its not that simple!

Most performance cars are tuned to make max power on 93 octane and running 100 wont to anything , but whatever !

Are we on "any car" forum? Nope. ;) I am saying the 2015-2017 Shelby GT350 should make more power with a higher octane fuel. :doh:

 

[Super Werty]

I worked at a shop with a dyno jet in the 90s
It was typical to go to a track and see older Vette guys running 100 octane n stock cars and not running any faster. I have never seen any stock car make more power with race gas but maybe the 5.2 is the exception.

I saw the 98 octane post and they claim a gain 30 ft pounds torque ! Lol

News flash... It's not 1990 anymore

 

[RonnieSVT]

News flash... It's not 1990 anymore

Im still stuck in the 80s

still the gt350 may be the exception for race gas but I still want more proof !

When was the last time you saw a post that said he wasn't stock he was using race gas to run faster than everyone else?
Its because race gas doesn't usually work on a stock car but maybe the gt350 is different!

 

[RonnieSVT]

oh btw I just checked the race gas dynos with 98 and it made 454 rwhp I thought 460 rwhp was the norm?
the claim is 429 rwhp stock then 454 rwhp with 98

This is what the poster had to say (Dynoed my new GT350 on the Dynojet at my son's restoration shop last Saturday. With pump gas that is supposed to be 91 octane, we got 429-434 wheel Hp (about 510 engine Hp at 85% driveline efficiency) in 3 runs with pump gas. We were down to less than 1/8 tank of gas, so we filled it with Sunoco 260 GTX 98 octane race gas, and were surprised how much the power increased. We got up to 450-456 wheel Hp, which would be about 535 engine Hp.

We were surprised at this increase, because we tried this on a completely stock 2014 Boss 302S that we dynoed a year ago. It showed essentially no change in power with 91 versus 98 octane with its street gas tune, and also no more power running its 100 octane tune on race gas (both tunes provided with the car by Ford). That engine put down about 392 wheel Hp, which would be about 460 at the engine.

My 2012 street boss that I am planning to retire as a track car, put down about 368 wheel Hp on pump gas, and the regular key versus the track key made no difference.)

 

[superman07]

Voodoo is not a typical oem motor.

My f150 with ecoboost also likes octane. Its more common for newer engines than you might think. The headroom Ford left on the Voodoo is a more extreme case though. Sometimes it is also that people get shit 93. From my limited reading this is the first of the Ford V8 builds that shows this level of improvement, including the Boss.

Ohio and PA do not test Octane.

Does 5-15 hp, or 20 lbs of torque win races? Who is driving?

 

[superman07]

oh btw I just checked the race gas dynos with 98 and it made 454 rwhp I thought 460 rwhp was the norm?
the claim is 429 rwhp stock then 454 rwhp with 98

credibility? every dyno is a bit different, I would think that if you worked with one in the 90s this would be elementary.

their test was same dyno, same car, same day, different gas.

 

[ITLRUN]

Im still stuck in the 80s

still the gt350 may be the exception for race gas but I still want more proof !

When was the last time you saw a post that said he wasn't stock he was using race gas to run faster than everyone else?
Its because race gas doesn't usually work on a stock car but maybe the gt350 is different!

Have you read your owners manual? Here are the two sections on Fuel from the main Owners Manual and the Shelby Supplement. :shrug:

 

[RonnieSVT]

it says max power with 93 or better !

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