before i install the eat chip

[1991 525i Novs]

hey guys

just a quick question, do i have to run my tank down and then fill it up with 91 octane gas cause i have been running 89 octane in it??

[Incantation]

i would

[SchnellE34]

Yes definitely, running on 89 with a chip could be harmful to the engine

[1991 525i Novs]

should i completely drain it, like how far down will be safe, until light is on, or what, need some advice boys, thanks




Yes definitely, running on 89 with a chip could be harmful to the engine

[ryan roopnarine]

if you are in the united states, you should have already been using 91 octane fuel, the damage has already likely been done, as you have a 10:1 compression ratio and no knock sensor (it says on your gas door to use premium unleaded gasoline). if you live in the US/canada, and are in an area with 93, just mix your remaining gas with 93, and, so long as you have 1/2 or less of a tank left, the average will be 91 octane,which is fine for the eat. i'm not trying to be a dick to you, but i don't know why people with m50s think that the presence of a knock sensor makes it OK to run less than premium. i'll occasionally run a tank of 87 (because somebody attempts to fill the tank for me), and no additional knock compared to 93 octane occurs.

[1991 525i Novs]

what kind of damage is done to the engine??




if you are in the united states, you should have already been using 91 octane fuel, the damage has already likely been done, as you have a 10:1 compression ratio and no knock sensor (it says on your gas door to use premium unleaded gasoline). if you live in the US/canada, and are in an area with 93, just mix your remaining gas with 93, and, so long as you have 1/2 or less of a tank left, the average will be 91 octane,which is fine for the eat. i'm not trying to be a dick to you, but i don't know why people with m50s think that the presence of a knock sensor makes it OK to run less than premium. i'll occasionally run a tank of 87 (because somebody attempts to fill the tank for me), and no additional knock compared to 93 octane occurs.

[ThoreauHD]

Yes, the EAT chip requires 91 or above. So just use most of the tank and filler up with 93. You can't use 87 anymore. I have the conforti, but it's pretty matched up with the EAT's.

You'll notice a good bit more pep all around. And your gas mileage will jump a few per gallon. Of course the gas costs more, but it's been very much worth it for me. I hate feeling like I need to push the car to get it to move. Also rev'ing to get on a highway or whatnot is very responsive.

Your engine will be fine. Just make sure everything is in good order- oil/filter/spark plugs/gaskets and it'll be happy.

[1991 525i Novs]

thanks alot, i know, i have it regularly maintained and its in great working order, im really excited about the extra pep, is the chip hard to install, anything i need to be careful about/ or just follow the bmwe34 site and i should be fine?




Yes, the EAT chip requires 91 or above. So just use most of the tank and filler up with 93. You can't use 87 anymore. I have the conforti, but it's pretty matched up with the EAT's.

You'll notice a good bit more pep all around. And your gas mileage will jump a few per gallon. Of course the gas costs more, but it's been very much worth it for me. I hate feeling like I need to push the car to get it to move. Also rev'ing to get on a highway or whatnot is very responsive.

Your engine will be fine. Just make sure everything is in good order- oil/filter/spark plugs/gaskets and it'll be happy.

[Mad M5]

In My place we use only 95 or 98 Octan and its ok to go for any of these petrol

it workrd fine for my late 525i M50 and great on my e34 540i auto (which is manual now )

[neil_004]

The directions on bmwe34 are good. Just be really carefull when you are removing any of the clips(at the connector and the post on the back of the board) and try not to bend the boards. Touch something metal and avoid carpet while you are in there(the static could fry the chip or possibly the ecu).

[NY535iManual]

This is a little bit of a related question I guess, and I know next to nothing about electronics, but does anybody know as a practical matter how often chips & ecus are damaged by static electricity? I've always used the little paper/wire grounding "cuff" that comes with chips, but if somebody didn't how great is the danger?

[liquidtiger720]

so the m50 non-tu dosnt have a knock sensor?


and the m50-tu has one? My tank says 89 as the lowest grade of gas...which is midgrade.

[Qube]

In reality, I'd do a shogun reset, drive it for a week, then chip it. Only then will you find a better comparison.

[ryan roopnarine]

so the m50 non-tu dosnt have a knock sensor?


and the m50-tu has one? My tank says 89 as the lowest grade of gas...which is midgrade.


yes to both. the m50 was kind of bleeding edge when it came out. while i'm sure that the knock sensor does an OK job with 89 octane, keep in mind that you still have a 10.5:1 compression ratio. technology really isn't able to overcome what grade of gas you can burn in such a motor. nobody assembling a motor from scratch would try to run 10.5-1 on anything less than premium. bmw may have been able to "engineer" a way around this, to an extent, but if i had an m50tu, i wouldn't bother running anything than premium. no, it isn't an alfa or anything with a 12-1 ratio, but its still an 11 year old car.