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Old 10-05-2009, 08:33 PM   #21
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Quote:
Originally Posted by mptoledo
I try to use the following site(click on retailer) as a general idea what gas isn't crap, but in my small area I am lucky to find a Shell station and Chevron is out of the question.
http://www.toptiergas.com/index.html

wow, we officially do not have a single one of those gas stations here in champaign/urbana. I just do not know what to say, our gas sucks... But being in the mid west we have good dirt and corn. Maybe thats why we have so much ethanol!

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Old 10-06-2009, 01:14 AM   #22
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Originally Posted by blue2000s
I don't know exactly what's in Race Fuels like Sunco that makes them different,.... The higher percentage of fuel allows it to have more energy content. It also keeps it from cleaning your engine and shortens it's shelf life.

If all else were equal, there's no point in buying a gas for a higher octane rating than 93 (or 91 for us at higher altitude). ...Using a fuel with a higher octane rating doesn't gain anything... You will also increase stresses on components and increase the temperature of the engine and cooling system.

The additives in a particular gasoline are what make up the different grades/octanes. BP, for example, starts with the same base and adds different things to it to make it low, mid, or high grade. In fact, mid grade is a 50/50 mixture of low and high grade often mixed at the pump.
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I have forced induction and a piggyback AIC (or call it a DME-lite) that leaves whatever Porches intent was as far as induction & ignition goes, somewhere back along the road.

Your right I suppose that more energy might create more heat but, a blower adds alot more though, an easy 125+ degrees to the intake temp. The hotter the charge the more it is likely to detonate.. Knock sensors will solve that by retarding the timing but, start Kissing performance away to.

The setup as designed is really pushing the limit on 93 octane (probably pre ethanol 93). We only have 91 oct. (except for 2 or 3 places across town) So, just to get it to that minimal 93, I have to brew my own from 91 and 100. I can't pretend to notice the dif between 93 or 91. I've been leed to beleive higher octane it a cooler burn. Keeping my piston from burning (they can) is my only concern. This thread complicates things a bit.

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Old 10-06-2009, 07:23 AM   #23
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I just came back from Des Moines and noticed that the national oil companies seem totally absent.

They had grades like Hy-Vy and the like. One assumes they buy there gas from someone else.

Yikes!
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Old 10-06-2009, 08:20 AM   #24
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Oh Hy-Vy rules, 8 essential vytamines and minerals in every tank.

To Blue200os's point, BP mixing the brew at the tanker/station, i think I've heard they all do that. They probably service the generics the same way. I was going to say hy-vy is not exactly prominent on the NYSE. Couldn't help but google it and it wasn't there either. ...very scary Bruce.

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Old 10-06-2009, 09:44 AM   #25
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Originally Posted by pk2
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I have forced induction and a piggyback AIC (or call it a DME-lite) that leaves whatever Porches intent was as far as induction & ignition goes, somewhere back along the road.

Your right I suppose that more energy might create more heat but, a blower adds alot more though, an easy 125+ degrees to the intake temp. The hotter the charge the more it is likely to detonate.. Knock sensors will solve that by retarding the timing but, start Kissing performance away to.

The setup as designed is really pushing the limit on 93 octane (probably pre ethanol 93). We only have 91 oct. (except for 2 or 3 places across town) So, just to get it to that minimal 93, I have to brew my own from 91 and 100. I can't pretend to notice the dif between 93 or 91. I've been leed to beleive higher octane it a cooler burn. Keeping my piston from burning (they can) is my only concern. This thread complicates things a bit.

PK
Adding a forced induction system to a high compression engine will certainly require an increase in octane rating in the fuel you use for safety. Compression pressure is higher, mixture temp is higher, cylinder temps are higher, the potential for hot pieces of residual carbon setting off the mixture prematurely is higher. Everything is there to allow for an unintended ignition. You would want the increase in octane to resist the chances. Actually, it's popular within the tuners of turbo engines to use E85 (speaking of E85) because it's octane rating is very high, which allows for high boost levels beyond what you can do on pump gas.
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Old 10-06-2009, 11:08 AM   #26
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Here's the official/unofficial word from a Porsche engineer on non-premium fuels (USA Today, 2003)


... All Porsche engines are designed for premium, but it's not available everywhere. "Our cars must be able to drive all over the world, and so we are able to run on regular," says Jakob Neusser, director of powertrain development at Porsche's research and development center in Weissach, Germany. "You don't have to feel that a mechanical problem or anything else will happen" using standard octane gas, even in the highest-performance, regular-production Porsches.

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Old 10-06-2009, 11:33 AM   #27
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Originally Posted by d18mike
Here's the official/unofficial word from a Porsche engineer on non-premium fuels (USA Today, 2003)


... All Porsche engines are designed for premium, but it's not available everywhere. "Our cars must be able to drive all over the world, and so we are able to run on regular," says Jakob Neusser, director of powertrain development at Porsche's research and development center in Weissach, Germany. "You don't have to feel that a mechanical problem or anything else will happen" using standard octane gas, even in the highest-performance, regular-production Porsches.
Yup, that's typical of all manufacturers. Most cars today are equipped with knock sensors that can retard spark timing to protect the engine from damage if the gasoline isn't of expected octane rating. There's a power penalty and some argue that the lower octane fuels don't clean the engine as well because of the formulation.
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Old 10-06-2009, 01:42 PM   #28
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Has anybody tried regular or even midgrade? I will stick to high grade until I can do some more research on the subject.

Also: Anybody have any input on mobil gas? I found a UDF (united dairy farmer) gas station and it's tanks are labled MOBIL.
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Old 10-06-2009, 03:29 PM   #29
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We keep a drum of race fuel at the shop for a customer who drives a 700 HP 964 Turbo we built. Even he could probably get by on premium pump fuel in it's current tune, but there's certainly nothing to be gained by running a higher octane than what is needed.
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Old 10-06-2009, 08:25 PM   #30
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Quote:
Originally Posted by blue2000s
Adding a forced induction system to a high compression engine will certainly require an increase in octane rating in the fuel you use for safety. Compression pressure is higher, ...You would want the increase in octane to resist the chances.
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All very true. Pistons can come to look like Swiss cheese fondue on a connecting rod to.
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Quote:
Originally Posted by blue2000s
Actually, it's popular within the tuners of turbo engines to use E85 (speaking of E85) because it's octane rating is very high, which allows for high boost levels beyond what you can do on pump gas.
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So what you seem to be saying is rating (burn starter energy), by whatever means (ethanol, whatever), is more important and the actual energy content doesn't matter much with a blower. In fact, the rational for the 91 oct. sects belief system is opposite to that which you are suggesting for this app.

Interesting about e-gas. I've not seen it...but I haven't looked either. What is it likely to dissolve?

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Old 10-07-2009, 11:37 AM   #31
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Originally Posted by pk2
So what you seem to be saying is rating (burn starter energy), by whatever means (ethanol, whatever), is more important and the actual energy content doesn't matter much with a blower. In fact, the rational for the 91 oct. sects belief system is opposite to that which you are suggesting for this app.

Interesting about e-gas. I've not seen it...but I haven't looked either. What is it likely to dissolve?

Regards, PK
Apparently, high boost and more fuel more than makes up for the difference in energy content.
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Old 10-07-2009, 07:24 PM   #32
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I used to get gas at a Sam's Club by my wife's work but they finally went with the 10% ethanol blended gas. I started to keep track of the type of gas I was using when my gas mileage started decreasing. The 10% ethanol gas reduced my mileage by almost 10% compared to straight gas and I found that others had discovered this also. I found this was the same with my motorcycles and one the bikes started acting up when cold, which it never had previously. What I don't really understand is, why the gas with ethanol costs the same as the gas without.
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Old 10-07-2009, 07:51 PM   #33
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There is a Tri-Par station on the way to Elkhart Lake WI (Road America) that I frequent every trip from northern Illinois in one of the P cars...around town it's Shell V-Power. The Box S likes it as does the '73 with carbs.

Thanks for the link...good stuff to know.
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Old 10-08-2009, 04:01 AM   #34
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fuel

I got my 2004 Box last May and since that time have put on 22000 km. I have kept track of every single fill up. Normally here in Winnipeg I use Co-op gas because in Feb they send you a rebate cheque which last year I beleive was for approx $.16 a litre. Anyway, where I am going with this is I recently did a 5500 km road trip over two weeks and I noticed when using Shell I got at least 10% more range (10% less fuel burn) on a tank. I used Sunoco 94 in Ontario where there iss no ethenol in the hi-test and got just as good if not better - the Sunoco was hard to find. Soon as I got back to Winnipeg back to the Co-op gas and my range on a tank dropped 10%. Interesting. Maybe it isn't such a deal.

On another road trip last winter I took my Acura TSX and in one state (WI?) there is ethenol in hi-test and my range dropped 10-15% and picked back up again after I was able to get fuel without ethenol.

My thoughts are that ethenol is crap. If polutants released into the air is a product of volume burned these days then with ethenol you are putting 10 - 15% more into the atmosphere and increasing your fuel costs by a similar amount. No saving anywhere that I can see.
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Old 10-08-2009, 10:33 AM   #35
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Quote:
Originally Posted by blue2000s
Apparently, high boost and more fuel more than makes up for the difference in energy content.
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Patience must be running dry but, my options now that I know of for 93 oct (what the cblower was set up for) are

100 oct race fuel ------------------------------------------------$5-6 per gal

114 oct. toulene (already about 15% in pump fuel)------$20/gallon

115 (?) ethanol---------------------------------------------------$10/gallon

Bang for buck aside, I wonder what is easiest on the motor. And, what exactly is susceptible to deterioration with ethanol.

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Old 10-08-2009, 12:56 PM   #36
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Originally Posted by pk2
----------------------------------------------------------------------------------------
Patience must be running dry but, my options now that I know of for 93 oct (what the cblower was set up for) are

100 oct race fuel ------------------------------------------------$5-6 per gal

114 oct. toulene (already about 15% in pump fuel)------$20/gallon

115 (?) ethanol---------------------------------------------------$10/gallon

Bang for buck aside, I wonder what is easiest on the motor. And, what exactly is susceptible to deterioration with ethanol.

Regards, PK
E100 is about 113 octane. If your goal is to hit 93 octane, using 22/78 race/pump gas your cost is at about 3.70/gal if you assume pump 91 is 3.00/gal.

9/91 toulene/pump is 4.50/gal

9/91 E100/pump is about 3.63/gal

This is just to get you to a safe octane rating. As we noted before, race gas will have more energy content than E100, so you'll make more power (and wear) on the race gas.

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Old 10-08-2009, 02:03 PM   #37
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Originally Posted by tnoice
wow, we officially do not have a single one of those gas stations here in champaign/urbana. I just do not know what to say, our gas sucks... But being in the mid west we have good dirt and corn. Maybe thats why we have so much ethanol!
Champaign urban? I live in Urban in Champaign county. Who would have thunk it. It might take a little leg work to find a station w/out Ethanol. I am still looking and the station attendants aren't too helpful either.
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Old 10-09-2009, 12:37 AM   #38
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Quote:
Originally Posted by blue2000s
E100 is about 113 octane. If your goal is to hit 93 octane, using 22/78 race/pump gas your cost is at about 3.70/gal if you assume pump 91 is 3.00/gal.

9/91 toulene/pump is 4.50/gal

9/91 E100/pump is about 3.63/gal

This is just to get you to a safe octane rating. As we noted before, race gas will have more energy content than E100, so you'll make more power (and wear) on the race gas.
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Thanks as always BLUE200OS,

Nice of you doing the arithmetic, I flunked that class. Pretty much my how I've been running it the majority of the time (8:2 piump). I usually wind up using toluene in pinch. It's a lot easier to find, in most hardware stores, than race fuel.

Ive got a custom made h2o/methanol injection sittimg on a shelf. Sure to relieve any angst with an effective octane well over 100 oct. on any grade pf fuel(from what I understand). Dont quite understand it but, Ive heard of people claiming the equivalent.118 on a 50/50 meth h20 mix, a little less with straight h20.

Regards. PK
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Old 10-09-2009, 02:39 AM   #39
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Does it make any sense to put in a gallon or two of race fuel with with every tank of high test? I have also noted that my mileage goes down (and maybe performance, hard to tell) with ethanol in the mix. BTW, I did a couple of dyno runs with my 2.7L and picked up a few HP running straight race fuel, that was an expensive, but fun experiement....

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Old 10-09-2009, 09:58 AM   #40
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Does it make any sense to put in a gallon or two of race fuel with with every tank of high test? I have also noted that my mileage goes down (and maybe performance, hard to tell) with ethanol in the mix. BTW, I did a couple of dyno runs with my 2.7L and picked up a few HP running straight race fuel, that was an expensive, but fun experiement....

Ed

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Well, you still have the same amount of ethanol which was what this thread was about, and for reasons I forget, till I hijacked. But good question, according to blue-s the ethanol just helps at detonation, race fuel should pack the rest of the energy on down the the hole, which ethanol won't...

On the other hand, why bother, your car shouldn't be noticeably faster with anything over 93 high test. 91oct and 2 gallons of 1000 should give every thin the alcohol dose plus the added punch...be like real 83 oct.

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