Just wondering if anyone else has come across this...

Yesterday I was driving the back roads North of Roswell when I came across a Shell gas station. I was about to just drive by when I looked up and saw the sign that said, "100 Octane Race Fuel"...it's on Crabapple Rd. (I think).

So, I had 2/3 of a tank of my standard BP 93...why not spoil the Eta some :) So I busted out my rainy day car fund and put in $20 worth (around 5 gallons) and proceeded to start her up and take off. Damn...that's some smooth action there. Not noticing as much power as much as smoother power deliverly across the board. ONLY problem is around 700-500PRMS before redline at WOT I get some hesitation. The car has never had it's timing checked since I got it (4 years) and well, it's an Eta with a JC chip and not tunned for (approx) 96 octane.

Still, I feel happy with spoiling my car some and giving it the really good stuff.

So, has anyone else seen this place?

-Prince

no, but that's pretty cool that it's available somewhere else than the track. I've never seen that before. :dunno

Directions? How much per gallon?

Yeh, where was it? Might have to check it out.

Yeah, Circle K/Phillips 76s have these pumps sometimes. There's on on exit 1 in SC coming from the west on I-20.

Anywhere near Roswell? Because of my tuning my car sees a big gain in smoothness and power when I run higher octane gas.

Dunno, but I'll be on the look out.

I have been going to that Shell station for a few years. It's only a few miles from my house. I used it in my lexus IS, 911 and now I run it in the M3. I have tried it straight and mixed with 93 with all three cars. Here is what I believe:
In all cars, the mix of 93/100 works as well as 100 straight. The mix almost instantly changes the throttle response and feels faster or snappier. I don't know if it really is faster or not but it does feel different. In the M3, 2 out of 4 times I have used the 100 octane I got a service engine soon light but it went away after 20-30 miles and didn't come back. The dealer said it wouldn't cause any problems and was tripped by an O2 sensor. From what I have read, the only thing the extra octane does is ensure the timming doesn't retard due to pinging. So with 93 there could be some slight timming retardation on hard accel and with 96-100 octane there is no pinging so no retardation needed. This keeps full hp on tap.

The price of this fuel was $4.29 per gal as of Saturday. A bit costly but cool for that every once in awhile treat.

Kevin, can you elaborate on its location?

Originally posted by Ali
Directions?

The station is located on Crabapple rd, on the Roswell/Alpharetta line, 4 miles north of Holcomb Bridge. The easiest way to get there from the south is to exit 400 at exit 7b go down Holcomb bridge past hwy 9 to Crabapple rd, take rt and go about 4 miles and the station is on the left. I think it's called Crabapple Corners Shell.

Thanks, thats not too far from me. Maybe I'll give her a drink of the good stuff for my trip to silver dollar next weekend. :)

Dayum, that's like 5 mins from me..I'll have to get some one time and see how the s/c'er does with it..lol..

I go there all the time. My 2002tii only runs well on 100 octane race gas after all it's mods. It runs 100%, which makes for some alarming fuel bills but oh the sweet smell and sound.

I always run into Turbo Porsches and Audis there but I've yet to see one BMW.
Must change this, huh?

Thats so funny someone brought this up. I started putting that gas in my 95 Cobra like five years ago. I have ran it in my M3 a handfull of times. The car definately runs better :redspot

Ya I live a mile away from that gas station but I figured everyone knew about it....

Well, looks like I'm not the only person that came across it...and the problem I stated with the weird actions at WOT near redline is now gone. After I took her for a longer drive the ECU figured everything out and she runs so much better now from 0-redline.

BimmerDawg wanted an idea for a meet. How about getting together for a quick gas-up at this place and a little drive around the back roads of Roswell. There are some sweet roads where I was Saturday.

-Prince

I think there's a place on Veterans Mem. Hwy. in Mableton/Austell that sells race gas too. Not a gas station, but a shop IIRC.

If they don't still sell it, they should take their sign down...

Carter

Originally posted by PrinceE30
Well, looks like I'm not the only person that came across it...and the problem I stated with the weird actions at WOT near redline is now gone. After I took her for a longer drive the ECU figured everything out and she runs so much better now from 0-redline.

BimmerDawg wanted an idea for a meet. How about getting together for a quick gas-up at this place and a little drive around the back roads of Roswell. There are some sweet roads where I was Saturday.

-Prince

Woooot, I'd be up for that! Sounds like there's alot of us up here in Roswell/Alpharetta area. I'm about 5-7 mins from that gas station. Gonna have to put a few gallons in for the baby to taste.. :D

uh guys, nobody here has a high enough static compression to warrant this stuff. I can see it helping Nick due to the blower, and possibly Minsoo due to head work and valve overlap, but not our cars. Remember, they are tuned to run optimally on 93, but will run ok on as low as 87. On a car with lower compression it is a total waste. I can see using a few gallons mixed with normal for running a track day in , say August for example. But for a street car running on the street, no way.
Remember, a fuels Octane rating is, basically, the flash point resistance determined by the additive package. This does not mean you get more power running this fuel. In fact, in some engines, you can effectively lose power as the fuel burns slower.
Now, if the fuels base stock is different, say a non-oxygenated fuel vs oxygenated(pump gas), then you could get more power, since the gas has a higher energy content from the get-go.

There is also a station on GA53 at 985 that sells 100 Sunoco should anyone still want to blow money for no apparent reason.

take this as you wish.

I went lookin for this place last night and I couldn't find it. I went up Crabapple by the Kroger and I didn't see a shell. Was I supposed to go a bit further north?

James is right. For a stock BMW, the race fuel is waste.
I don't believe the stock ECU would be able to advance the timing enough to take advantage of 100 octane.

My Tii is running 11.5 to 1 compression with an MSD 6A race ignition and a 292 cam, so it NEEDS this. It doesn't have a computer to back the timing down if I run lower octane.

Originally posted by MGRMLN
James is right. For a stock BMW, the race fuel is waste.
I don't believe the stock ECU would be able to advance the timing enough to take advantage of 100 octane.


Since my ECU was reprogrammed by Dinan do you think I would see any gains by using the fuel? Or would I fall under the stock category

stock. remember, even Dinan has to program for fuels that are available. You might get 1-2 hp in the rpm range somewhere if you were lucky, but is that worth a $3 a GALLON premium to you?

The only time this would have any remotely appreciable effect is when the car is very hot and is under heavy load, such as a track day. Even then, no way worth the extra cost. The difference in available power would fall well within the statistical error range of a dyno.

Originally posted by MGRMLN
James is right. For a stock BMW, the race fuel is waste.

whatever, you guys are crazy. I betcha my busted ass 318 will gain 100HP at the wheels easy if I put this stuff in. :buttrock I better find some tires that'll handle all that power... I hope I don't blow up my diff! :laugh

:awink:

:rofl: :rofl: :rofl:

Yeh, I know its not going to benefit us that much. Its not like I'd be expecting hp increases. My thinking is that a light mix would ensure the ecu doesn't ever retard timing. Especially for those of us using performance chips with oxygenated fuels. You know, just to be sure your getting the max. Just a thought......I could be totally off base.

Interesting links on the subject:

Everything you ever wanted to know about racing fuel (http://www.turbofast.com.au/racefuel.html)

Another Fuel link (http://www.briggsracing.com/tech_tips/#fuel)
- "The octane rating is not the only element that controls the rate of the burn. The air/fuel ratio, the valve configuration, and the shape and size of the combustion chamber will all have an effect on the rate of burn.

-This would indicate to get the maximum output the lowest octane rated fuel must be used which will not cause preignition. Remember that as components are changed in the engine the fuel that is required may also change."

BTW, I'm with James on this one. Running higher octane than what your engine is tuned for (stock vs. w/SC, chip, etc) is a waste of money unless you need to for detergent and composition needs (i.e. I put 93 in my 540 for the low-sulfur characteristics that is has at BPs in Atlanta.)

Fun with science!

No, I agree also. I'm just thinking out loud so-to-speak.

If factory cars are programmed to run with 93, then a chip must be even more aggressive in its timing/fuel curves. If the car is constantly on the edge of knock would a few gallons of the 100 (I'm not talking filling up here folks) mixed in with the 93 give the ecu a little more room to breathe? Not that I'd do this regularly, just curious if thats false thinking.

I thought M3s were factory set for 91 octane? In this case, running 93 (premium in most Atlanta stations) should make up for any inconsitiency in the fuel quality. If you're on the edge of knock, yes, this (100 octane) would most likely solve your problem, but I think you might be better off financially either, 1) getting some fuel additive and putting it in every fill or 2) switching gas stations to maybe get a more reliable quality of gas.

As much as I drive...$4/gallon is a :nono

16gal x $4/gal = $64 a tank!!! Just for a placebo effect in our cars

Originally posted by rwindleyme02
I thought M3s were factory set for 91 octane? In this case, running 93 (premium in most Atlanta stations) should make up for any inconsitiency in the fuel quality. If you're on the edge of knock, yes, this (100 octane) would most likely solve your problem, but I think you might be better off financially either, 1) getting some fuel additive and putting it in every fill or 2) switching gas stations to maybe get a more reliable quality of gas.

Oops, wasn't thinking. You're correct since they have to accomodate Cali and other states that don't allow 92 or 93. But IIRC most chips are programmed for 92 or above (unless you get a cali specific programming). Also, aren't our motors 10.5:1 compression? That is a high compression motor in my book.

I don't necessarily hear knock/ping (doubt I could even if there was knock since there is soo much insulation) and I always run Chevron or Amoco 93. But my thinking is if I know I'm going to beat on the car (ie mountain drives/track days where I'm constantly at or near redline), would a good octane booster or a mix of fuels prevent any knock that might occur?....especially, like James said, in the summer months since I'm not running a fan.

Again, this is not my area of expertise so I'm just fostering a good debate. ;)

Ryan,

Possible, but unlikely. Factory programming is aimed at the median- i.e., not all cars are maintained in tip-top condition, so the programing is set to allow for some inconsistencies in a given cars condition. That said, the tuners software pushes the maps further towards the high end of the acceptable range for the expected motor configuration.
It cold possibly help, just a little, but then again maybe not at all. Depends on the car, since there is a certain percentage variation in the following production parts-
piston height
size of valve depressions in piston
size of combustion chamber in the head
etc,etc,etc......


For a track day at RA during August, maybe 2 gallons would help, maybe not. I think it is more a peace of mind kinda thing......

Also, the no-fan thing shouldn't effect this, since by the time you would really be hammering it, you should have more than enough airflow over the rad for proper cooling to occur.

James

Peace of mind :)

I understand the chemistry of it, being an engineer, but there's something about saying, "yeah, I use race fuel from time to time in my car." that just makes me feel all warm and fuzzy inside :) If nothing else, the smell is amazing!

-Prince

Originally posted by Sparc_it
I went lookin for this place last night and I couldn't find it. I went up Crabapple by the Kroger and I didn't see a shell. Was I supposed to go a bit further north?

It's about another mile or two north of the Kroger.

Originally posted by atlantaM3
Ryan,

Possible, but unlikely. Factory programming is aimed at the median- i.e., not all cars are maintained in tip-top condition, so the programing is set to allow for some inconsistencies in a given cars condition. That said, the tuners software pushes the maps further towards the high end of the acceptable range for the expected motor configuration.
It cold possibly help, just a little, but then again maybe not at all. Depends on the car, since there is a certain percentage variation in the following production parts-
piston height
size of valve depressions in piston
size of combustion chamber in the head
etc,etc,etc......


For a track day at RA during August, maybe 2 gallons would help, maybe not. I think it is more a peace of mind kinda thing......

Also, the no-fan thing shouldn't effect this, since by the time you would really be hammering it, you should have more than enough airflow over the rad for proper cooling to occur.

James

I agree, and like you said, with a tuned chip, you're already pushing the "factory envelope." Honestly, I'd experiment with diffierent fuels if you're having knock issues.

I did a lot of research on fuel when I had my 540 Nikasil problem (wrote letters to companies and such) and it seems like BP was the only one to give me a consistently high range of quality with Cheveron and Shell coming in a close second. This is due to BP voluntarilly refining thier "Ultimate" fuel to 2006 standards in some cities where pollution is a problem ( I'm guessing they get some tax break or subsidy b/c of this). Atlanta happens to be on of these cities. Asheville is another.

Also, you may experience knocking more at different times of the year as gas companies serving different regions change thier formula slightly to account for the climate change.

Again, good discussion here. If it makes you "feel better" to give your car a drink of the good stuff every once in a while, go for it. Add it to your mods list too. ;)

My car definitly sees a big gain from a mix of 100 and 93 octane, of course i'm not stock software or motor anyways. I don't run a fan at all and with the 100 octane race gas at the dragstrip my temp stayed in the middle (although we know that isn't the most precise measurement of temps) but at least it didn't creep past that. With race gas, my clutch slips on hard shifts and my tires break traction in 2nd to redline as they did not do that with regular gas before. However, I'm not baller enough to run $4.XX a gallon gas.

Originally posted by Ali
However, I'm not baller enough to run $4.XX a gallon gas.



Yes, you are.

add it to my mod list...lol. :biglaughb So I guess the "refined" fuel BP is talking about is Amoco Ultimate since thats what they're all using. I split between that and the Chevron....I've never had a problem with either. Good stuff :)

James,
yeh I guess that when it comes down to it, it is a piece of mind thing. My car ain't no spring chicken @ 140k, but I drive her like she's at 70k. She runs great, but I firmly believe its the maintence I've done and the products I use. Regardless I can't deny that she's getting older. Honestly for $4/g I'll probably just run good octane booster (http://www.essexparts.com/newproducts.html#PBoost) from time to time when I want the extra "fuzzy feeling". The $$/octane point would be better since I wouldn't run straight 100 anyway. $60/tank.....yah right.

Yeah, my car felt less "sluggish" and more responsive with the race fuel. Maybe its a placebo effect, but after I went back to pump gas my clutch slipped no more :dunno maybe I should do a dyno back to back with race gas to see if there's any difference?

I don't doubt your findings Ali. You hit the nail on the head - Your motor is heavily modified and you have highly tuned software for your application, just the setup where you would see a benefit from higher octane fuel.

Ali,
As far as your motor, were any of the following things done?-
head shaved to decrease size of combustion chamber
cams installed with a low degree of overlap
non-standard pistons installed
custom software with VERY aggresive timing advancement

These are the major things that would cause a shift in octane requirements for a motor.

The 'pep' you felt was probably a result of the fuel being non-oxy, which Sunoco 100 is IIRC.

The difference should not be enough to cause clutch slippage, etc however. We are talking about a few horses, 5 tops, here.
You sure the clutch is in good shape?

The motor was built by Chuck Stickley (or more so his shop I guess) its a ltw head with a 3.2 bottom end, 5 angle valve job, custom cams, I believe higher compression, obd1 converted and some other purty stuff. Its also got a 7.5k limiter. (I posted all the stuff in the registry) yeah I think the drag racing did help with the clutch slipping too ;) but the increase in power was noticeable :dunno