Performance Chip and Gas Grade

[Greg325i]

Do all chips such as the Turner Motorsport Conforti Performance Chip for my 1994 325i require 91 octane gas? Will some chips work on lower octane gas but with not as much power gain?
I will be adding a cold air intake (aFe most likely) before considering a chip, all else is stock.

Thanks

[roybotnik]

You can run lower grade gas in the car because the knock sensor will cut back the timing and whatnot, but it isn't recommended because doing so pretty much sets you back at stock or worse. You would definitely want to listen for the 'pinging' that knocking causes if you put a lower grade gas in.

[RamGoat]

stop being cheap....the car requires premium gas anyway...plus why are you worried about ga anyway, you drive a BMW...:dunno

[Pilgrim]

Those are good points, and constantly depending on a knock sensor for safety is a very bad idea. They can fail like another other sensor, and if they fail at the wrong time on a motor that's running low octane fuel, you're screwed.

[SPElectronics]

I can understand why some people are worried about gas. It's freakin EXPENSIVE, and climbing daily right now! If you're a poor college student, or high schooler, or a fast food employee, it might take your whole check to fill up. LOL

I always use premium in my bimmer, but I cheap out in some of my other vehicles, but they were designed to run the lower grades.

[Pilgrim]

Premium gas is much cheaper than an engine rebuild.

[Blanco]

I can understand why some people are worried about gas. It's freakin EXPENSIVE, and climbing daily right now! If you're a poor college student, or high schooler, or a fast food employee, it might take your whole check to fill up. LOL

I always use premium in my bimmer, but I cheap out in some of my other vehicles, but they were designed to run the lower grades.

If you're that poor, you should be driving an economy car.

[jijacob]

If the car says 87, use 87. 93 won't do jack squat.

If the car says 89, use 89. 93 won't do jack squat, but 87 could hurt if your knock breaks.

If you spend $300 on a chip/injection and it says to use 91, FREAKING USE 91.

If gas is too expensive, either take the chip out or sell your car for a Toyota Yaris. They get great gas milage.

[Blanco]

I'm surprised people are so willing to run basemaps without actual dyno tuning for their specific engine.

[scabzzzz]

Umm... if you put the better gas in, its not going to cost you anymore in the long run. If you fill up on higher grade gas, you will be able to drive longer on that tank rather than filling up on lowest grade. Give it a try and compare the two. Better gas will only help your fuel system. The detergents keep the injectors clean, fuel lines etc... Its a win win situation. m50's + need the better gas. I mean they run a pretty delicate evap system and EFI. Why not?

[patmcd]

Umm... if you put the better gas in, its not going to cost you anymore in the long run. If you fill up on higher grade gas, you will be able to drive longer on that tank rather than filling up on lowest grade. Give it a try and compare the two. Better gas will only help your fuel system. The detergents keep the injectors clean, fuel lines etc... Its a win win situation. m50's + need the better gas. I mean they run a pretty delicate evap system and EFI. Why not?

Using 91 octane gas will NOT give you better fuel economy! All the grades of gas contain the same additives. They vary some from brand to brand, but not by grade. 91 oct gas only gives higher resistance to detonation.

[MR.E36i]

You can run lower grade gas

[sprocket1200]

My experience running 91-94 has been that with 50,000 kms on the spark plugs, they were checked and not a problem found. put them back in and kept going

car pulling strong and running great. maybe running 91 doesn't get better MPG, but it may save money otherwise...

[Blanco]

Octane is only for resistance to detonation. Nothing more.

Read and be enlightened. :)
http://209.85.165.104/search?q=cache:4b4oEwdAs5YJ:www.oregon.gov/ODA/MSD/docs/pdf/gas_octane_guide.pdf+octane+facts&hl=en&ct=clnk&cd=2&gl=us

[SPElectronics]

If you're that poor, you should be driving an economy car.
I agree. Although, that "economy car" would probably cost a hell of a lot more than the used E36... I know I couldn't get a GOOD economy car that I would want to drive, for what I paid for my 325i. Maybe a used GEO... LOL

Hell, I don't see why anyone wouldn't use premium in their bmw's AFTER chip considering you're supposed to be running it PRE chip anyway. Why chintz on fuel in these cars anyway? Drive less if you can't afford the fuel prices, or go siphon your neighbors... J/K!

[JunzieB]

Using 91 octane gas will NOT give you better fuel economy! All the grades of gas contain the same additives. They vary some from brand to brand, but not by grade. 91 oct gas only gives higher resistance to detonation.
I beg to differ:confused .... I actually tried it and i noticed that i got better mileage out of 91 octane as opposed to 89.:D

[Blanco]

I agree. Although, that "economy car" would probably cost a hell of a lot more than the used E36... I know I couldn't get a GOOD economy car that I would want to drive, for what I paid for my 325i. Maybe a used GEO... LOL

Hell, I don't see why anyone wouldn't use premium in their bmw's AFTER chip considering you're supposed to be running it PRE chip anyway. Why chintz on fuel in these cars anyway? Drive less if you can't afford the fuel prices, or go siphon your neighbors... J/K!

You don't a think a 220hp JDM K20 swapped Civic hatchback for $8k (same price as a 328) would be fun? It'd be faster than an M3. My '91 Si, with a 160hp SOHC VTEC engine, was just a hair faster than my 325 and just as much fun to drive. It cost me right around $5k including the engine build. It just didn't have the luxury, the name, or the high expense to own. I average 24mpg in my 325 and 28mpg in my Civic. And that's just one economy car, there are dozens of others out there if you aren't (pardon me) too stuck up to be seen driving them. When it comes to down to having cool things or eating, a choice many college students have made, I choose eating. If you're in college you're probably headed towards a good job. Buy a nice car then. :)

[pnyklr]

regular $2.35 a gallon x 15 gal = $35.25
premium $2.55 a gallon x 15 gal = $38.25

$3 dollars not that much more if you think about

[Blanco]

You guys didn't bother to read the link I posted did you?

But, again, these cars are supposed to have 91 octane anyway.

[DiScoTeknix]

You guys didn't bother to read the link I posted did you?

But, again, these cars are supposed to have 91 octane anyway.
S50/S52's are tuned for 91. The M50/M52's are tuned for 87.;)

You are correct in saying that higher octane fuels only provide better knock resistance as they are slower burning. In other words... there is a good chance you might loose a horse or two by using 91 octane fuel in a car that is tuned for 89.

[SPElectronics]

You don't a think a 220hp JDM K20 swapped Civic hatchback for $8k (same price as a 328) would be fun? It'd be faster than an M3. My '91 Si, with a 160hp SOHC VTEC engine, was just a hair faster than my 325 and just as much fun to drive. It cost me right around $5k including the engine build. It just didn't have the luxury, the name, or the high expense to own. I average 24mpg in my 325 and 28mpg in my Civic. And that's just one economy car, there are dozens of others out there if you aren't (pardon me) too stuck up to be seen driving them. When it comes to down to having cool things or eating, a choice many college students have made, I choose eating. If you're in college you're probably headed towards a good job. Buy a nice car then. :)

I'm definitely not against driving those cars. I have owned LOTS of hondas, since the early CVCC's. I own a 94 Accord in fact, have had it since it was new (it cost a lot more than 5-8k though). I only paid $2800 for my 325i, and I didn't find many decent "econoboxes" in that price range that I WOULD drive though. I'm definitely not opposed to building another import though, but I do love my bimmer! I like the luxury, and the quality, and so far I have had very LOW maintenance. Upgrades and stuff like that cost me more than anything. Same deal with other brands though. I also wouldn't really call the BMW crap when it comes to mileage, when you consider the performance they have as well right out of the box. To get 18-30mpg in a bimmer, is pretty impressive. I get 26-33 in my Accord (last time I drove it anyway), which is a big jump, but it certainly isn't as impressive overall as the bmw. I have friends that race Hondas, and I ain't talking just "cheap ass street racers", I'm talking fully built billy badass types, and even their personal daily drivers that are somewhat built, don't get great mileage. The more you build em, the less mileage you get outta them typically. That's a sacrifice you gotta make sometimes.

That's just my thought on that subject. I agree with you though for the most part.

[SPElectronics]

regular $2.35 a gallon x 15 gal = $35.25
premium $2.55 a gallon x 15 gal = $38.25

$3 dollars not that much more if you think about

Wow, where the heck are you getting gas? Our low grade is now at 2.57 per gallon even at most of the cheapest stations. I want to be where you live! lol

[Blanco]

S50/S52's are tuned for 91. The M50/M52's are tuned for 87.;)

You are correct in saying that higher octane fuels only provide better knock resistance as they are slower burning. In other words... there is a good chance you might loose a horse or two by using 91 octane fuel in a car that is tuned for 89.I was under the impression that 95RON was 90-91 in the U.S. and my owners manual says "90AKI or 95RON".


I'm definitely not against driving those cars. I have owned LOTS of hondas, since the early CVCC's. I own a 94 Accord in fact, have had it since it was new (it cost a lot more than 5-8k though). I only paid $2800 for my 325i, and I didn't find many decent "econoboxes" in that price range that I WOULD drive though. I'm definitely not opposed to building another import though, but I do love my bimmer! I like the luxury, and the quality, and so far I have had very LOW maintenance. Upgrades and stuff like that cost me more than anything. Same deal with other brands though. I also wouldn't really call the BMW crap when it comes to mileage, when you consider the performance they have as well right out of the box. To get 18-30mpg in a bimmer, is pretty impressive. I get 26-33 in my Accord (last time I drove it anyway), which is a big jump, but it certainly isn't as impressive overall as the bmw. I have friends that race Hondas, and I ain't talking just "cheap ass street racers", I'm talking fully built billy badass types, and even their personal daily drivers that are somewhat built, don't get great mileage. The more you build em, the less mileage you get outta them typically. That's a sacrifice you gotta make sometimes.

That's just my thought on that subject. I agree with you though for the most part.

Totally, I'm not saying these aren't nice cars that aren't worth the money. They certainly are. What I'm saying comes down one word, priorities. Some people just put showing off way too high on their priority list and end up chained to the things they own. That's just not something you should do if you're already broke. I see too many nice cars owned by people who can't really afford them past the purchase price.

edit:
Damn this forum moves fast.

[DiScoTeknix]

I was under the impression that 95RON was 90-91 in the U.S. and my owners manual says "90AKI or 95RON".
You are correct, 95RON is about 91US. Seams some cars were different than others. My 97 328 said 89 only on the gas door. I'll check and see what my 325 says.

Edit: 325 gas door says 89AKI. Weird.:dunno

[Blanco]

Maybe another difference between the M50/M52 and the jump to OBDII?

[DiScoTeknix]

Maybe another difference between the M50/M52 and the jump to OBDII?
My old M52 also said 89. I'm stumped haha.

[pnyklr]

http://www.gasbuddy.com/gb_gastemperaturemap.aspx

[Greg325i]

Wow! Posted this question and when I got home from work there was already 24 replies.

I am not trying to be cheap as some have suggested, just don't want to throw money away either. If the car would still run OK with the chip and use 87 or 89 octane gas why not. I realize that while using the lower octane gas it would not produce as much power, just was not sure if the new chip would let you use the lower octane gas and still run OK without pinging while producing less power. I thought that the 1994 325i's were tuned for any grade, but after reading some comments and looking closer at my manual I see that I should be using 89 octane. The manual says at the bottom of the page that 87 octane can be used but that "In this case slight influence on engine efficiency can be expected." I am sure that means gas mileage and power if the anti-knock control is retarding, changing the air-fuel mixture or what ever else it would do.

Gas in my area is at $3.11/87 and $3.33/91, but as one reply stated that is only about $3.50 more per tank.

I have been trying all grades and can tell some difference between 87 to 91 octane. I will start using 91 octane all the time and am eager to get the cold air intake and then the chip. Should be within the next few weeks.

P.S.: This is my first BMW and have only had it for about a month.

Thanks for all the replies.