can't wait to see your car break 130mph.

 

No need for a flip switch on mine. It's been programmed to run on both reg and race gas. That is not a reg tune. It's custom for mine. The highest unleaded you can get is the VP MS109. There is no unleaded 110. Sure there's the C12, C16, 110, 114 etc but those are leaded.

No use in mixing. Stick with what you want.

 

there are 110 octanes ... Torco has one and Rockett is 111.

James can you also explain how you have a tune that is for 100 octane and 91 at the same time?

 

Yes there are 110's, 111's and higher but those are all leaded.

 

How is that possible? I mean yea the car will run on either octane gas but if you run a car thats tuned for 100 octane on 91 octane you will get detonation since the car has advanced timing. This is why most other car tuners (pretty much everyone but mercedes tuners) program a "pump" file and a "race" file.

SLK55R- I doubt I will ever see 130 traps unless I strip it completely and turn it into a tin can on wheels. If I do hit 130 traps I will do a backflip! Or at least attempt to and maybe break my neck in the process and die a happy man

Oh, and there are 110 octane "unleaded" fuels.

 

I know for a fact that LET will have this soon.

 

i'm REALLY waiting for someone to explain these dual tunes and offer some proof. it's only 5 years late to the ballgame, but better late than never...if it's all true anyways.

 

what do you mean explain?

One is a ecu tune for 91 octane or 93. Another is a tune for specifically 100 octane ... whats not clear?

 

When you tune for higher octane you make more power because you can add more timing (and boost but this is more applicable for turbo cars since in order to change boost on a sc car you have to change the pulley) without detonation. Alot of tuners have a pump file and race file and you can switch tunes based on what gas you are running. I don't know why benzes never had this and still dont as of yet. It's very common in the tuner world

 

you asked the same question...

 

i guess i didn't word my post properly. i'm sure you know that i understand tuning but what i don't understand is how jame55 has a tune that runs on both pump and race gas (assuming it can take full advantage of both). i also want to know more about the rumors that renntech and let are supposedly working on this.

regardless, i've always wondered why, if our ecu specifically have settings for different pump gas octanes, tuners are so *******g late to adapt those settings to 110, 100, 91 octane!!! i'd buy a starscan tool in a heartbeat if that's all i needed to switch between different maps. seems like it would be so easy knowing that our ecu's already have the capability to store different maps.

oh well, wtf do i know...

 

Yea I know that you know about tuning which is why I was confused for a sec. My fault. I can't answer that question because I have no idea

 

sorry Chiro ... I misunderstood what you were asking, just like blackbenz.

I think all 3 of us are stymied on how James can have a tune that is optimized for both.

 

Cory from Kleemann "custom" tuned my ECU to take advantage of the higher octane (race gas) since i told him that the car will be mostly running race gas unless i go for a long trip like las vegas etc.

Not exactly sure what the details is but i think Cory tuned it in between? I'll try and get more details for you guys.

But i know for a fact that i had an increase in power when he dynoed it in CO.

 

101 octane is close to $7.00 per gallon.....

 

What that means to me is he compromised. He needed to give you a tune that on 91 won't detonate ... as a result he has not giving you a tune that is optimized for 100 octane. Sounds like he just gave you a slightly more aggressive tune than stock 91.

out here Torco 100 is $5.99 now and SP 100 is over $7.

Heh this is good news! Just means there is more hp on tap on that beast!

 

Yes i believe that's what he did but can't confirm since i can't get a hold of him.

VP 101 is $9.xx gal this past weekened.

 

He is on vacation this week

 

All hope is lost..................temporarily until he gets back. lol

 

Do you mix it with 91 or pure 109? Must be a PTA to fill-up with 4 cans every few days.

btw... Vadim still has my car.. Installing UDP, Dual X and Intake Mod. I just called him and asked tuning it for 93 or above and he does not recommend it. It will gain 10-15 extra rwhp but the dependence on race gas will be a major hassle.

 

Really? That's cheap for California

 

Depends. Sometimes i mix it sometimes full 109. Saved up a few cans for those rainy days. And not really a PITA since it's a weekened toy.

 

[quote=Marcus Frost;2872903]Guys, do a search for this, it's been discussed before. I've tried this with my E55 and documented it - ZERO HP gain, and the car actually runs worse on anything above ~93ish octane. The ECU mapping just does not give headroom for extra timing or anything above that octane, so it is a total waste.

Remember - the rule of thumb on octane is you want to use the LEAST amount of octane before the car detonates/preignites/etc - higher octane is harder to burn (ie, requires more ENERGY) and unless you can actually take advantage of it, will net LESS HP all factors BEING EQUAL.



THIS IS TOTALLY FALSE

airplanes and race cars use high octane 100-118 because it does in fact provide more explosion and power per given unit than lower octane,

also it does not knock, in fact it burns much more completely and easily and faster with less residue, THAT IS WHY AIRPLANES USE IT,,
otherwise you get knocking at 30000 ft, your screwed. RIGHT?

ask any pilot,, or me lol

fact is higher octane provides more HP and better milage and is more efficient.. PERIOD, ask any refinery tech, engineer, or race car team I did..


now its true the ECU will adapt up to about 95-96 because that is what they run in europe , but its also try that beyond that, you need a ECU tune and reflash to extend the timings etc to take advantage of anything beyond like 95-96..

I tried it both before and after ECU tuning.. and it helps just with the higher octane,, mixed with 91 octane to give around 94-95.. makes car slight quicker and seems to run better and for sure increased milage about 1 mpg

AFTER ECU tune.. it helped ALOT,,seems to have a flatter and wider more even torque curve , and gets about 2MPG more.. in average..according to my logs etc..

so put like 2 gallons 100 OCT in for say 18 gallon tank and rest 91-93 without ECU tune and it will adapt, air fuel and timing..

and put like 3-4 gallons in for ECU tuned car.. seems to be best ratio I have tried..

anyone that says it does nothing is either stupid or high, its the law of physics, cause the explosive power and efficiency is increased

why race cars and airplanes use it after all lol

hope that helps

 

no disrespect intended...but you're way off on your understanding of why hp is made with higher octane fuel. octane rating by itself does NOT equate to more energy or more hp.

 

the added power is not specifically from the octane rating. I think the confusion comes from the fact that most 100 octanes have oxygen adders which do improve power. For some brands its one specific reason why 109 might make less hp than 100. The 109 doesn't have the oxygen adders so potentially can make less HP. Thats why they recommend you run on 100 if you aren't detonating. Of course this all has to do with your tune.