With the Rising Gas Prices has anyone.....?

[Anthony_D]

Has anyone tried out running mid grade in your g35?I drive a 2004 coupe with a little over 50k miles. I have been contimplating filling up with mid grade (which i believe is 89 octane in Vegas) has anyone tried this? Are there any major conciquences? (i.e. damage to fuel management system)

Looking forward to your feedback.

Thanks Guys!Anthony - Las Vegas

[SVTCOBRA]

Welcome to Nico!!!

Most of the places here it's only 10cent difference.

But, when I had two pathfinders, I could run middle grade in my stick, but had to run prem in the auto. Is yours an auto or stick?

[Anthony_D]

is an auto,

I dont understand why the transmission would matter though?

[ArizonaG35]

Welcome to Nicoclub Anthony! Glad to have you aboard. There's many schools of thought on this subject. I personally do not believe that there is that much of a cost benefit from using lower grade octane. Afterall, if economy was your goal, then the G was probably not the best choice.

I'm sure some guys will chime in with their opinion...

*Sniff* *Sniff* *Sniff*I think I smell a Telcoman comment coming along soon!

Welcome again to Nicoclub!

Dave

[SVTCOBRA]

Must be the way you shift before bogging down the engine. imho an auto shifts too late.

If it were mine, I would stick with Prem.

If I felt I had to switch, I would run my tank down to near empty and put in 1/2 tank and make sure it doesn't knock. If it does, then I would fill it the rest of the way with Prem.

[SneaKe]

I ran 89 for a full 2 tanks. I did not notice any issues. I'm back to premium though, as I'm concerned with watered down tanks of reg. Since premium is selling less, stations are running out of reg very quickly, and its tempting for them to water it down, rather than run out and have to wait for the gas truck.

Some might think I'm kidding, but I'm not. 2 people at my job fell victim to watered down gas. In both cases, they lost their car for 3 days while the dealership tried to figure out what was wrong, only to come to the not so obvious conclusion.

Gas stations are plauged by the 'occasional' arrival of their delivery truck. I worked at one for a bit, and am good friends with the owner of another. Gas trucks never show up on time, and you have to order a certain quantity before they will even concider coming to you. Many stations in NJ have been running out of regular grade because of the increased demand, and the slow responce of the refuelers.

I don't know if most people know, but 'midgrade' is simply a tank inbetween the regular, and premium. First they fill a 'set' amount of premium into it, then they let the regular tank overflow into the midgrade. Depending on who's doing the filling, you may find midgrade to be the same as regular.


Modified by SneaKe at 5:18 PM 5/21/2008

[rn79870]

Welcome to Nico. telco87man will be along pretty soon to tell you all about 87 octane.

[Sentientbydesign]

Eww. I've been worried about this for a while. Can we class action sue them?

To the OP:

The difference in price between premium and regular is around $.20/gallon. Which means for a completely empty tank...$4.

Let's say you go through complete tanks a month. That's in the neighborhood of 1200-1900+ miles per month. You're saving all of $16 by going with regular and about $8 with midgrade...WHY?

Go swap the car over to amsoil synthetic (engine, transmission, differntial) and you'll probably save $.12/gallon and quite a bit in "missed" oil changes.

Which is cheaper than premium.

[telcoman]

Welcome to Nicoclub Anthony! Glad to have you aboard. There's many schools of thought on this subject. I personally do not believe that there is that much of a cost benefit from using lower grade octane. Afterall, if economy was your goal, then the G was probably not the best choice.

I'm sure some guys will chime in with their opinion...

*Sniff* *Sniff* *Sniff*I think I smell a Telcoman comment coming along soon!

Welcome again to Nicoclub!

Dave

LOL

Just use regular and faaget about it. As goes the price of gas, so goes my 401k plan

[rn79870]

LOLJust use regular and faaget about it....

Uhm, what do you mean by faaget? I'm a little nervois now.

[SVTCOBRA]

Just use regular and faaget about it. As goes the price of gas, so goes my 401k plan

Yep, do as Telcoman says:Use 87 octane.Do not ever 'flog' it.Only drive on flat terrain.

No worries!!

Only need to move up in octane if you hear knocking! (however, I've read that damage can be done even if you don't hear it pinging....) But, the owner manual does say 87

Good luck!!

[Beancooker]

Different fuel for coupe vs. sedan.

Different flash on the ECU?

[joe603]

I agree with Bean...do what your manual recommends, the savings are not significant.

Search this topic if you'd like to know more...there was a long thread posted a while back.

[JettaRed]

I use water injection on my Audi TT for performance enhancement when running higher boost levels. I actually use windshield washer fluid which is approximately 40% methanol and 60% water. As a result, I have been able to run higher boost and advance the ignition timing offset by +4.5◦. Estimated hp increase is 20 hp. So, with a chip, water, boost increase and timing increase, I’ve been able to bump my hp to 300 hp. So what?

I know that there are some applications for non-turbo cars to use water injection with high compression engines. It may be worth considering water injection to use lower grade, less expensive gas (we are about 24 cents apart in price between regular and premium) except would you would need to use 1417 gallons (or 27,000 miles) before you hit the break even point. (The cost of a good progressive water/methanol injection kit starts at $330 from Devil’s Own Alcohol Injection.)

[Anthony_D]

Thank You all for your insight! And the warm welcom to Nico!

I just wanted to make sure there were no extreme risks with using a lower grade. I understand that the savings is not signifigant however it was mostly for the circumstances where premium was not available.

And thanks for the constructive criticism ArizonaG35 maybe i will just trade it in... (!!!NOT A CHANCE!!!)

Thanks Again guys! i will post some pics when i get a chance...

[Anthony_D]

thanks for the graphic! Much appreciated!

[telcoman]

Welcome to Nicoclub Anthony! Glad to have you aboard. There's many schools of thought on this subject. I personally do not believe that there is that much of a cost benefit from using lower grade octane. Afterall, if economy was your goal, then the G was probably not the best choice.

I'm sure some guys will chime in with their opinion...

*Sniff* *Sniff* *Sniff*I think I smell a Telcoman comment coming along soon!

Welcome again to Nicoclub!

Dave

LOL



Telcoman

[SVTCOBRA]

Different fuel for coupe vs. sedan.

Different flash on the ECU?

I had actually broke out the manual when I saw this thread come up!I wasn't sure if there was a difference in the MT and AT Sedans.I could have sworn that I read that 'they' recommended Prem for 6MT Sedans and all coupes.......but, perhaps that was somewhere else....I know my sedans PING with regular.

[snwbrdr435]

I think i read somewhere that the pinging can sometimes only be heard with those things the doctors wear and around there necks and walk around looking important with the name escapes me at the moment.

[JettaRed]

I think i read somewhere that the pinging can sometimes only be heard with those things the doctors wear and around there necks and walk around looking important with the name escapes me at the moment.

LOL! If you can hear pinging with a stethoscope, you're pretty fricken brave or you have very serious engine problems.

Pinging usually occurs under load, such as going up hill, towing, or hard acceleration, which means the car is moving. If you are hanging out of the engine bay while someone is racing the car, that's pretty brave.

[telcoman]

I had actually broke out the manual when I saw this thread come up!I wasn't sure if there was a difference in the MT and AT Sedans.I could have sworn that I read that 'they' recommended Prem for 6MT Sedans and all coupes.......but, perhaps that was somewhere else....I know my sedans PING with regular.

All Fords ping. Its disatisfied former owners shooting at them.

[navyseal]

It is funny to read this thread b/c i recently got bored and kind of did a comparison of gas prices and how much it costs from regular (87) to premium (93). First of all it is recommended to use Premium gas in the g35 coupe. The engine is built to run on 93 octane. Through using 93 octane you get better response time, better gas mileage, cleaner, more crisp and efficient gas. So anyways, my girlfriend lives in Georgia and I live in Florida. I got bored and started comparing differences in gas prices. In Florida at the time I was paying $4.09 for a gallon of gas of 93 premium octane. In Georgia as we all know has some of the lowest gas prices, a gallon of 93 premium octane there was $3.97 if I remember correctly. So what I did was compare gas prices at 15 gallons of gas. What I found was that the only difference in price was $2. Two dollars folks that is ALL. I was shocked b/c i was always so adamant about filling up in GA and saving myself some greenbacks. My .02 about filling up with either midgrade or premium is GO for the PREMIUM. For goodness sakes you bought a INFINTI/SKYLINE G35 and should not have to question yourself about these things. If your honestly worried about saving a couple of bucks here and there while you spent 25 thousand dollars plus on a car than maybe you shouldn't own a car in the first place. (that is not directed to anyone in specific just talking out loud) the least you can do is treat her right, rub her on the a$$, give her a kiss and fill her up with some premium. They don't call it Premium for nothing

[ArEs23x]

The only thing I will say is I realize gas is expensive, but when it comes to your "G" never worry about gas and just drive your car and treat it right with premium even if you spend those extra couple dollars at the gas pump

[SVTCOBRA]

Telcoman, I think I saw your 58 ford coming at me the other day on the way home! Two toned white and some ugly orange/red persimmon color. Looked brand new!

[apm285]

What are you guys paying for a gallon of premium gas these days?

Here in Australia we pay $1.60 per litre for 98 octane when converted to a gallon its equal to $6.10.

[JettaRed]

What are you guys paying for a gallon of premium gas these days?

Here in Australia we pay $1.60 per litre for 98 octane when converted to a gallon its equal to $6.10.

Then you’re really need to hope it doesn't get that expensive here!

I was listening to Bloomberg radio yesterday and it was mentioned that many developing countries will be stopping subsidies that they have been giving to keep the cost of energy down so that their economies can grow. While the effect may be a slowing of the global economy, it certainly is going to slow oil consumption. World demand for oil was given as the explanation for the sudden doubling of oil costs in the last year (yeah, right!).

[WDRacing]

This thread has a lot of misinformation...becareful what you read on the internet.

As far as water or any type of subinjection goes when thinking in terms of a naturally aspirated motor things are far trickier then running it with boost. The purpose of the subinjection is to cool the combustion charge effectively allowing you to run more boost and or timing. However, when you have a turbo compressing and heating the air charge as well as increasing the cylinder pressure and in the same instance increasing the combustion temps, the benefits and tuning of the alcohol or water injection are clear and easy to attain. The usual reason for adding subinjection is so you can add more of something to the motor, like boost and timing in most cases, not so you can actually lower the octane required for the motor to maintain it's normal operating parameters.

When decreasing the combustion temps by adding water and or alcohol, you also seriously lower the efficiency of the motor. By this I mean, heat is power. Especially in a naturally aspirated motor. When you spray water into the intake of the motor, you're lowering the combustion temps by close to 200 degree's F even with a small jet. Yes you can now run a lower octane, but how are you controlling the on/off points of the pump? I suppose MAF voltage could be used to insure the motor is actually under a load. Tuning would have to be done via EGT gauge for sure, or you'll only be running 87 octane at the cost of really bad gas mileage. Not to mention that lowering your combustion temps increases the amount of emissions and lessons the ability for the CAT to filter them out.

All in all, using water injection as a means to run lower octane is a bad idea. If you were to increase the compression to 11.5:1 or install a turbo...then I'd be all for it. But running subinjection as a bandaid fix for lower octane isn't a good option. Not to mention the cost for a good fail safe system will be about 2 years worth of cost compared higher octane fuel.

WD

[rn79870]

All Fords ping. Its disatisfied former owners shooting at them.

Ahhh. It's so clear now. Your 58 Ford didn't start becasue.....

you ran 87 octane in it

It all makes sense now....

[JettaRed]

This thread has a lot of misinformation...becareful what you read on the internet.

As far as water or any type of subinjection goes when thinking in terms of a naturally aspirated motor things are far trickier then running it with boost. The purpose of the subinjection is to cool the combustion charge effectively allowing you to run more boost and or timing. However, ...

Thanks for the comment. I was wondering if anyone has tried water/meth injection for a N/A engine. There are forums that discuss it, but I was trying a short cut. And you are absolutely right. Forced induction is a totally different animal. Lastly, the cost of implementation and the obvious threat to any warranty claim makes it an unattractive option.