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Brenspeed 87 octane mileage tune.


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I was wondering that myself. If his tune can give us the same performance or better and run on 87 or 89 gas, that might be worth while.

 

I seriously doubt you would get the same performance or better on 87 or 89 gas. Maybe these cars should have two, separate fuel tanks - one that you can fill w/ 89, and the other with 93 or higher....then a switch on the dash to switch between the tunes and tanks....

 

Or...just install this system... Steeda's Adaptive Performance Calibration....

 

http://www.steeda.com/news/steeda_news/02-...calibration.php

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When I ordered my tunes for the Shelby GT,Brenspeed said they had a tune specifically for mileage on 87.Not really a performance tune but more for mileage.Anyone that has a brenspeed tune and tuner may want to call them and see about it.At the time I didn't go into detail about mileage improvements and that specific tune because fuel was in the $2.00 range.Now that it is about $4.00 for 87 it might benefit some of you guys and gals that drive a lotWith the GT500 I don't have that option :banghead: I might call them on tuesday and see how much of an improvement it can give.I'll post up whatever they tell me.

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THe Hypertech I have has an 87 tune and it works fine. If I used my car as a DD maybe but since it is a weekend car, I pt it back to 93.

 

The first tank of gas we bought for the SGT was hi test. The next tank was mid grade. No knock -- no adverse affects. We went down to low grade and the car runs fine... actually gets a bit better gas mileage.

 

If the car doesn't knock or ping, there is no detonation going on and the lower grade of fuel is fine. I know several other enthusiasts and gear heads who do the same thing. You can't do it with a supercharger or turbos because of the increased compression ratios, but it's fine to try otherwise. If it does start to knock, just drive it easy until the tank is 1/2 full, then fill it with hi test.

 

The problem with using too low an octane gas is the possibility of detonation (or ping/knock - sounds like marbles rattling around in your engine under load.). Manufacturers usually recommend higher octane gas for cars that may be driven harder over long periods of time, but under normal conditions it's a waste of money. Hi test produces a slower burning spark, which gives the pistons a chance to get to the top before the explosion produces power to push the piston back down. Lower octane gas produces a faster burning spark which may cause the explosion to occur before the piston reaches the top. Then you have the situation where the push rods are pushing the pistons up while the explosion is forcing it down. The result over time and high load could be damage to the engine. It's why retarding the timing will solve the problem. It also reduces power.

 

Since this only happens under load, driving the car mildly until the low octane burns out will prevent the detonation. But this is usually not necessary unless you hear the detonation.

 

With the price of gas it's worth a try.

 

Also, the higher the altitude, the lower your octane can be. It's why octane in mountain states ranges from 85-91 while lower areas have 87-93.

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Some things to consider here...IMHO.

 

Using a lower octane fuel may produce detonation, as previously explained by our friend, "old guy", ^ there. He's not wrong, but he is light on details. Allow me to expand on this topic?

 

Think of detonation as a long-term illness, like a slow-growing cancer, meaning that it takes a while for the damage to come to the surface. Nevertheless, it will come to the surface.

 

The damage I speak of, is to the native hyperereutectic formed aluminum pistons, which are super-saturated with 16 to 18% silicon content. This piston is coated in Teflon to protect the silicon, and detonation eats away at Teflon until it reaches the native silicon. Then, detonation melts the silicon, and eventually, your pistons are toast. Thanks to our SAI/FRP programming, you will not hear this detonation. The EEC will pull spark, timing and fuel faster that you can read those words. When you do hear detonation (engine rattle), it's too late.

 

Once this process has started and the Teflon is eaten away, your pistons will come apart. The first to go will be the piston crown, which holds the primary compression ring in place. After that, the piston skirts burn up and score cylinder walls. Friction is heat, and higher heat accelerates more melting. Once the skirts break off and fall into the oil in the crankcase, it's over.

 

Thus...Lose your compression ring and you lose it all, and your engine will appear to have a gazillion miles on it, when it does not. Moreover, your factory warranty will be void, FMC knows more about what to look for than y'all believe. Where do you think I learned this?

 

Our friend "old guy" also mentions pre-ignition as a possible outcome of running lower octane, but he doesn't clarify the difference between detonation and pre-ignition. Again, I agree with him, but here's some additional background.

 

Pre-ignition occurs when the fuel charge ingnites before the piston has come to the top. Preignition is a short-term (and usually instant) fatality, like getting shot to death rather than dying from cancer.

 

As the piston is on it's way up into a compression stroke, an over heated piston top (thanks to detonation) fires the fuel charge prematurely, before managed EEC tables, and forces the piston to suddenly change direction and go down rather than up. This is extreme force meeting extreme force head to head, think of two linebackers crashing? Nonetheless, this crash force damages the connecting rod causing it to deform side-ways, rather than up-and-down.

 

The connecting rods on our SGT 4.6L-3V engines are made of powered metal, formed by compressing powered metal dust into solid objects. Just like wood based MDF/particle board, under normal compression they are stronger than you would ask for. However, push them the wrong way and you get dust again. Pre-ignition does exactly that, pushes the con rods in the wrong way, and you will know the outcome immediately. Again, your factory warranty will be void, FMC knows more about what to look for than y'all believe. Where do you think I learned this?

 

Remember...I live in Chicago, and today (5/24/2008), 93 octane is 4.59.9 per gallon, so, I'm not without sympathy for the question at hand. I wish there was an easy answer, but I don't know. De-tuning the SGT may be okay with the right tuning touches. It may not.

 

I conclude (very reluctantly) that retuning an SGT for lower octane does not sound like a good idea to me. The pennies saved at the pump need to be kept in a jar on your countertop for future expenses. A replacement engine is 6700 bucks not including install, and you won't get these failures past FMC labs. Our short blocks have been on the street too long to fool them anymore.

 

Do what you gotta do, eh?

 

Just my .02C on it all, happy motoring, gents.

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[size="3]LuLu, you are lucky to be able to buy 93 octane. About 1/3 of the country is stuck with 91 as the highest we can buy and that is right on the line. I hope SAI did a conservative tune as even Vegas, if I am not mistaken, has only 91 octane as the highest. I don't know who would do the warranty review as the 4.6 liter 3V is made to run on 87 and it is only after the SAI tune and CAI, et al, that the octane requirement is bumped to 91. Would SAI or Ford do the review? Either way I agree with you. Buy the best, TOP TIER gas and the highest octane.[ And losing the block is a quick way to lose money off of your SGT if you are contemplating holding it for an investment someday./size]

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Some things to consider here...IMHO.

 

Using a lower octane fuel may produce detonation, as previously explained by our friend, "old guy", ^ there. He's not wrong, but he is light on details. Allow me to expand on this topic?

 

Think of detonation as a long-term illness, like a slow-growing cancer, meaning that it takes a while for the damage to come to the surface. Nevertheless, it will come to the surface.

 

The damage I speak of, is to the native hyperereutectic formed aluminum pistons, which are super-saturated with 16 to 18% silicon content. This piston is coated in Teflon to protect the silicon, and detonation eats away at Teflon until it reaches the native silicon. Then, detonation melts the silicon, and eventually, your pistons are toast. Thanks to our SAI/FRP programming, you will not hear this detonation. The EEC will pull spark, timing and fuel faster that you can read those words. When you do hear detonation (engine rattle), it's too late.

 

Once this process has started and the Teflon is eaten away, your pistons will come apart. The first to go will be the piston crown, which holds the primary compression ring in place. After that, the piston skirts burn up and score cylinder walls. Friction is heat, and higher heat accelerates more melting. Once the skirts break off and fall into the oil in the crankcase, it's over.

 

Thus...Lose your compression ring and you lose it all, and your engine will appear to have a gazillion miles on it, when it does not. Moreover, your factory warranty will be void, FMC knows more about what to look for than y'all believe. Where do you think I learned this?

 

Our friend "old guy" also mentions pre-ignition as a possible outcome of running lower octane, but he doesn't clarify the difference between detonation and pre-ignition. Again, I agree with him, but here's some additional background.

 

Pre-ignition occurs when the fuel charge ingnites before the piston has come to the top. Preignition is a short-term (and usually instant) fatality, like getting shot to death rather than dying from cancer.

 

As the piston is on it's way up into a compression stroke, an over heated piston top (thanks to detonation) fires the fuel charge prematurely, before managed EEC tables, and forces the piston to suddenly change direction and go down rather than up. This is extreme force meeting extreme force head to head, think of two linebackers crashing? Nonetheless, this crash force damages the connecting rod causing it to deform side-ways, rather than up-and-down.

 

The connecting rods on our SGT 4.6L-3V engines are made of powered metal, formed by compressing powered metal dust into solid objects. Just like wood based MDF/particle board, under normal compression they are stronger than you would ask for. However, push them the wrong way and you get dust again. Pre-ignition does exactly that, pushes the con rods in the wrong way, and you will know the outcome immediately. Again, your factory warranty will be void, FMC knows more about what to look for than y'all believe. Where do you think I learned this?

 

Remember...I live in Chicago, and today (5/24/2008), 93 octane is 4.59.9 per gallon, so, I'm not without sympathy for the question at hand. I wish there was an easy answer, but I don't know. De-tuning the SGT may be okay with the right tuning touches. It may not.

 

I conclude (very reluctantly) that retuning an SGT for lower octane does not sound like a good idea to me. The pennies saved at the pump need to be kept in a jar on your countertop for future expenses. A replacement engine is 6700 bucks not including install, and you won't get these failures past FMC labs. Our short blocks have been on the street too long to fool them anymore.

 

Do what you gotta do, eh?

 

Just my .02C on it all, happy motoring, gents.

 

Interesting... I have never heard of anything like this.

 

I do have a question, tho.

 

The Mustang GT has a recommended octane rating of 87 octane (low grade.) The engine uses the same hypereutectic formed aluminum pistons as the SGT along with all other internal parts. A huge selling point is that the GT will run on regular gas. Shelby knows its customers don't really care about that (or at least they didn't.) The SGT also has the same anti-knock sensors that retard timing to the point where detonation will be eliminated (not "almost" eliminated.) Given this, wouldn't it suggest that the elimination of detonation will prevent damage? I obviously have never heard of this "slow death" that you speak of.

 

Running with hi octane gas allows the spark to be advanced to provide the better performance that Shelby is looking for (accounts for a good portion of the +19 HP - the rest is accomplished with a better breathing intake and exhaust, thus the need for the tune). But the way I am reading your explanation, it is the pre-ignition that damages the Teflon. It seems that with the anti-knock sensors retarding timing, it has to eliminate all pre-ignition to eliminate detonation (that is its sole purpose.) Without pre-ignition I can't see how there would be a slow erosion of the Teflon. So are you saying that the anti-knock sensors and the computer don't eliminate all of the knock?

 

I'm not suggesting that you are wrong, only that I don't understand how "slight detonation" could exist with the anti-knock sensors and how a tune could mask the unmistakable sound associated with it.

 

Why would Shelby recommend a higher octane? Simple. They need to advance the spark to obtain the higher HP rating. Shelby wants a higher output than the standard GT, and allowing the spark to advance further is an easy way to get some extra poop.

 

Also, another question that you said to ask...

 

How do you know this?

 

Thanks.

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I have the brenspeed tune on my car and i have it set for 93 octane. Shelby sets there tune at 91 octane. Here in Houston the octane is 87-89-93 octane so i was burning 93 octane anyhow. Breenspeed does have the 87-91-93 octane settings but at 20cents difference between 87 and 93 octane i think i would not take any chances. Brenspeed probably will tell you that you can set to 87 octane but these increases are probably here to stay so why would i drive at 87 octane when i could get more performance at 93 octane. Isn't that why we bought these cars in the first place. If we think we are burning a lot of fuel on our muscle cars then look at the old cars of the 50-60-70's. Tell these guys you are getting 20to22 mpg and these guys will be ready to sell there's.Makes us look pretty smart doesn't it. I was at a cruise in tonite and there were probably 150 cars there.These gas prices keep going up and we will probably see a big drop off in participation,unless you are getting 20mpg.

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Lots of thoughts here, gents, and this is good. Anytime you want to explore new territory, gather all the 411 you can before starting out.

 

The 4.6L-3V engine is very durable and can take a lot of punishment, but you have to play inside the rules too. Octane is key, but not the critical element here. You could slip by with some 87 octane if necessary, but you should avoid hammering the throttle when this is the case. What is very critical, is the tune and how the engine behaves in WOT. If you turn that over to an aftermarket tuner, he has to be up on his game. Run lean with the pedal to the metal, and you will hurt something. My advice is that if you are going to handicap performance, handicap your driving habits as well.

 

"Spark knock, ping, detonation and pre-ignition", call it what you want. No two engineers will agree on defining the sound. But, they don't have to agree, just work to eliminate it. Ford's knock sensors are tuned to one frequency, thus they will report only certain sounds at specific points within the RPM range. The EEC cannot react to what it isn't told by sensors, and spark knock can occur anywhere in the RPM range, any time. Insulated inside the passenger compartment, you prolly won't hear a lot of this lower level pinging, and in WOT I doubt you would hear much at all over the volume of the engine as a whole. This is why I called it a slow silent death. Moreover, if you do hear "rattles", your tune is in serious trouble.

 

This isn't a new topic for Ford engineering, it's been a concern since the development of the modular engine. I'm rather impressed with their accomplishments over the years, but durable doesn't mean you can toss some rules out the window. When you add/modifiy your tune with an aftermarket program, it is that tuner's proficiency and talent you are employing. If he decided to throw a rule or two out the window, you own it. You may not suffer any harm for quite a while, a lot depends on your driving habits. Me? I'm fairly hard on things, which is why I haven't tampered with the stock tune. BTW, you can easily blow a custom built forged bottom end with the wrong tune on it.

 

"How do you know this?" Fair question. Our modular 4.6L block has been around a while, and I've been driving on it since 1997. I've built them for performance and I've blowin them up. A few years ago, I owned the Kenny Brown Marauder S, the "1X" magazine car. While trying to build and tune this car, I met many of Ford's engineers. I put 30K+ miles on one car just traveling back and forth between Chicago and a half dozen locations in and around Detroit. Engineers love to chat, and love it even more when they can teach. I listened and learned, and now I'm passing this along to y'all. I don't know everything, just a few things about modular engines.

 

Last, but not the least...Since the debut of the S197 Mustang, Ford engineers can tell you have an aftermarket tune on the car. There's a chip in the EEC that records flashes, and very few people have access to it. Once you flash over the stock tune, a trail is left behind. Should you seriously damage the engine, Ford will replace it and take your hurt engine and EEC back to Livonia, MI. Once they add up the damage and discover you flashed the EEC, you get a bill. They don't need to prove what failed. They only need to prove owner tampering, or, failure to maintain.

 

BTW...It's in our SGT supplement, "Octane Requirements" on page 6, in bold. "Customers are required to use 91 octane fuels at all times. Any failures associated with the non-use of premimum 91 octane fuel will be ineligible for warranty repair". Seems to me that Ford and Shelby couldn't enforce this without knowing a lot about it. I believe they do. If you are comfortable with the risk of 87 octane and aftermarket tuning, then drive on.

 

Just my .02C on it all, happy motoring, gents.

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I have the brenspeed tune on my car and i have it set for 93 octane. Shelby sets there tune at 91 octane. Here in Houston the octane is 87-89-93 octane so i was burning 93 octane anyhow. Breenspeed does have the 87-91-93 octane settings but at 20cents difference between 87 and 93 octane i think i would not take any chances. Brenspeed probably will tell you that you can set to 87 octane but these increases are probably here to stay so why would i drive at 87 octane when i could get more performance at 93 octane. Isn't that why we bought these cars in the first place. If we think we are burning a lot of fuel on our muscle cars then look at the old cars of the 50-60-70's. Tell these guys you are getting 20to22 mpg and these guys will be ready to sell there's.Makes us look pretty smart doesn't it. I was at a cruise in tonite and there were probably 150 cars there.These gas prices keep going up and we will probably see a big drop off in participation,unless you are getting 20mpg.

 

If you go a couple hundred miles West of Houston, and from there to the Pacific, you can only buy 91 octane. Something to think about if you ever travel. Even if you go to Vegas (Mecca) they only have 91.

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As I found out about 2 weeks ago when I took the SGT to a funeral, because a pump says 93 does not mean it is so. I stopped by a joe-blow gas station in Quitman and fueled from their 93 pump. Not putting any demand on the car, it wasn't until we got to Winnsboro and I went to pass another vehicle that I discovered their 93 was not 93. The car was pinging horribly! A $8 bottle of Octane boost cured the problem but it tought me when you need the good stuff, go to a reputable gas station.

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As I found out about 2 weeks ago when I took the SGT to a funeral, because a pump says 93 does not mean it is so. I stopped by a joe-blow gas station in Quitman and fueled from their 93 pump. Not putting any demand on the car, it wasn't until we got to Winnsboro and I went to pass another vehicle that I discovered their 93 was not 93. The car was pinging horribly! A $8 bottle of Octane boost cured the problem but it tought me when you need the good stuff, go to a reputable gas station.

Interesting...I don't know if a bottle of octane boost can solve such a problem, I never looked at that aspect before.

 

What's happening around here, is that gas station owners of ill repute slip the gas delivery man some cash to drop 87 octane into the 93 tanks. The state and city inspectors are overloaded with complaints, and one station has been shut down. Can you imagine the cash-in-pocket profit for the gas station owner?

 

Oh, and BTW...Found this...Hope it helps explain what can happen when octane falls below a recommended range. It's a bit dated, and general in scope, but still an interesting read. You should be aware that our SGT engines are 9.8:1 compression.

 

http://www.misterfixit.com/deton.htm

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LuLu - This is some pretty interesting stuff. Thanks for your insight. I will be looking into this a bit more as I had never heard this before you brought it up, but in the mean time I'll have Pauline start using hi-test. Thanks for bringing this up.

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So far, I still have plenty of non-Ethenol based 93 Octane in my area. Actually, it's new and good info to know it's not available everywhere. I mean that sucks, but it's good to know ahead of time.

 

Couple of questions on that for everybody out there:- Where is 93 Octane not available (from everybody's personal experience)?

- Would Octane booster be a good short or long term solution for if i'm in areas where 93 Octane is not available (not sure if that stuff has any negative effects)? That is easy enough to carry in the trunk.

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Interesting...I don't know if a bottle of octane boost can solve such a problem, I never looked at that aspect before.

I have never had luck with the cheapo brand. I normally keep Lucas brand octane boost (about $10 a bottle) with me for emergencies but did not have one that particular time. I stopped by an Alco in Winnsboro (mini wal-mart) and they had something called 107 boost or something like that. I was not expecting it to work but after letting it mix, it seemed to do the job well.

I recommend the Lucas (although at $10 it's just cheaper to put in 93) but the "107 boost" was a one time only experience.

 

The misses and I were talking today and after seeing a fuel bill of nearly $500 last month, we are going to park my truck, I'm going to drive the Hyundai Sonata (her current DD) and she is turning the SGT into a DD. I am going to detune the car back to 87 (her company pays for her fuel and would not appreciate the Premium demand) and see how it works out. She knows what to listen for as far as pinging and knocking so we will see. I'll keep an emergency bottle of Lucas around just in case.

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So far, I still have plenty of non-Ethenol based 93 Octane in my area.

OMG...The would be like a shot of Jack Daniels to LuLu, loosen her up a bit because everything in Illinois is a 10% ethanol mix.

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I have never had luck with the cheapo brand. I normally keep Lucas brand octane boost (about $10 a bottle) with me for emergencies but did not have one that particular time. I stopped by an Alco in Winnsboro (mini wal-mart) and they had something called 107 boost or something like that. I was not expecting it to work but after letting it mix, it seemed to do the job well.

I recommend the Lucas (although at $10 it's just cheaper to put in 93) but the "107 boost" was a one time only experience.

 

The misses and I were talking today and after seeing a fuel bill of nearly $500 last month, we are going to park my truck, I'm going to drive the Hyundai Sonata (her current DD) and she is turning the SGT into a DD. I am going to detune the car back to 87 (her company pays for her fuel and would not appreciate the Premium demand) and see how it works out. She knows what to listen for as far as pinging and knocking so we will see. I'll keep an emergency bottle of Lucas around just in case.

Thanks, stump, and good luck with the tuning.

 

Like I said, I don't know much about octane booster, so, I started a thread asking for input. Hope you don't mind.

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So far, I still have plenty of non-Ethenol based 93 Octane in my area. Actually, it's new and good info to know it's not available everywhere. I mean that sucks, but it's good to know ahead of time.

 

Couple of questions on that for everybody out there:- Where is 93 Octane not available (from everybody's personal experience)?

- Would Octane booster be a good short or long term solution for if i'm in areas where 93 Octane is not available (not sure if that stuff has any negative effects)? That is easy enough to carry in the trunk.

 

 

Apparently about 100-200 miles West of Houston the gas becomes 91 octane only for premium. This extends all the way to California and apparently North from that point. 91 only in New Mexico, Arizona, California, apparently Oregon, California, Nevada and north. Don't know why. Have tried to find 93 octane on the internet in Arizona without luck.

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OMG...The would be like a shot of Jack Daniels to LuLu, loosen her up a bit because everything in Illinois is a 10% ethanol mix.

 

Yea, actually just saw my first station that said it could be up to 10% Ethenol a week ago (at a non-name-brand station). Probably has something to do with me living on the coast and there being a major pipeline going up the coast. Before hurricane Catrina, we had the least expense gas in the country. But, prices jumped up then, and never recovered.

 

I stick with the BP (Liked it better when it was Amaco) premium unleaded as my first choice, then Shell premium unleaded if that is not available.

 

But, does sound like I need a couple cans of premium octane booster in the car for emergencies.

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I seriously doubt you would get the same performance or better on 87 or 89 gas. Maybe these cars should have two, separate fuel tanks - one that you can fill w/ 89, and the other with 93 or higher....then a switch on the dash to switch between the tunes and tanks....

 

Or...just install this system... Steeda's Adaptive Performance Calibration....

 

http://www.steeda.com/news/steeda_news/02-...calibration.php

 

Maybe, maybe not. Brenspeed improves or current tune, there's no reason to think they can't do a good job with an 87 octane tune. You have the right idea with two tanks, but your just thinking about it from the wrong end. My factory supercharged 89 Cougar XR7 came with a switch on the dash so you could switch between Premium fuel or regular. An easily switchable tune might be worth while for some who drives a long distance to work. (if it was cheaper than the Steeda one you linked to). I do like what I read on Steeda's sight. I wonder if that's the tune on the Bullitt.

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