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Dr. Flyview
09-13-2007, 09:02 PM
Hi,

I have heard people say performance chips (I have a MarkD) can lean out the engine too much and cause the valves to burn. A month after I put it into my non-vanos engine I had a hole in my valve (not saying it was because of the chip, but it DID happen). Replaced that motor with a vanos, and ran a chip again another 4 or so months no problems (till I crashed into a tree).

Now I have a new car and am debating putting in the chip or not. Should I check my A/F ratio before I put it in to make sure it's not already close to lean? Would this information be on my emissions test sheet?

Thanks,

Flaviu

R.S.C
09-13-2007, 09:42 PM
What car did you pick up

Dr. Flyview
09-13-2007, 09:45 PM
7/94 325i 5spd sports package, 160k.

craz azn
09-13-2007, 10:33 PM
Just don't buy a Dinan chip. That is all.

Dr. Flyview
09-13-2007, 10:34 PM
Just don't buy a Dinan chip. That is all.

?? C'mon guys explain a little. I've got a MarkD chip.

Furious
09-13-2007, 10:56 PM
nothing wrong with dropping 50 bucks for a run on the dyno to see where your ballparking after a few mods. chips typically lean the car out because the lean side is the powerful side, however the trade off is your flirting with a dangerous situation where if you lean out too far , bye bye engine. short of that, you will really never quite know what is the actual issue at hand.

craz azn
09-13-2007, 11:08 PM
Thats pretty much all that the Dinan chips do. They just lean the shit out of the engine timing and it obviously produces major detonation.

I have seen a Dinan, Conforti(TMS also I believe) and MarkD chips back to back for an e30 M3. The Dinan was by far the worst. The Conforti and the MarkD chips were similar, but the MarkD chip had a bit of an edge over the Conforti.

Furious
09-14-2007, 12:25 AM
ive heard that the only good chip dinan makes is for the 318's but its only something i heard. i have no clue, i had a markd chip in my 325 when i had that engine and she ran the car beautifully

kevin325
09-14-2007, 12:18 PM
ive heard that the only good chip dinan makes is for the 318's but its only something i heard. i have no clue, i had a markd chip in my 325 when i had that engine and she ran the car beautifully

whats the wtf in your sig suppose to be??

propr'one
09-14-2007, 12:29 PM
^^that's julian.


The AFR's from mark's chips i've seen are pretty much 12-12.5 right across the board, which is pretty much perfect. If you trust the tuner, you dont even have to get an AFR unless you have reason to believe something is wrong.

Having said that, as mark said, a 2-3 pulls on a dyno is like 50-60 bucks, with AFR, if you're worried about a car, dyno it.

Furious
09-14-2007, 01:16 PM
whats the wtf in your sig suppose to be??

thats me, my car, slovaniaboy and his car, last years bimmercruise. if you look closely you can see julian (Gamite) in the background giving us the finger.

pretty funny actually..



Proprone is correct markd's chips are pretty spot on, id look into other possible issues for your leaning out issue.

Dr. Flyview
09-14-2007, 01:18 PM
Well I have no idea if the new car is running lean but if it is b/c of some other problem and I put in the chip I'm ****ed...just don't know if I should take the chance.

Furious
09-14-2007, 01:19 PM
Well I have no idea if the new car is running lean but if it is b/c of some other problem and I put in the chip I'm ****ed...just don't know if I should take the chance.


dyno the car with AFR

/end until you get the results

T.Dot_E30
09-14-2007, 01:20 PM
did you use premium gas when you had the chip at all times?

Dr. Flyview
09-14-2007, 01:37 PM
did you use premium gas when you had the chip at all times?

Yea. so AFR wouldn't be found on emissions test eh?

Furious
09-14-2007, 01:42 PM
Yea. so AFR wouldn't be found on emissions test eh?



no your talking Lean/Rich values, emmision are based on these values but arent the same.

propr'one
09-14-2007, 01:47 PM
Well, i think the E-test does give you an afr at 2000RPM or something but you're looking for consistancy during the RPM range. Get a dyno done. Dont worry about the chip, your car has knock sensors, it will retard the timing if need be.

Dr. Flyview
09-14-2007, 01:52 PM
Dont worry about the chip, your car has knock sensors, it will retard the timing if need be.

Isn't that if you use octane that's too low? How would that help too lean a mixture?

propr'one
09-14-2007, 01:55 PM
just running a motor too lean can, and will eventually damage it even without knocking. But just for a reference point for you.

My motor is a m52b28, pretty much stock. I'm running s52b32 software on it (litterally, took the chip out of a M3, put it in my car, no tuning).

Because of things like the Maf, CPS, O2 sensors, etc, your chip makes sure its running correctly. You can usually tell a poorly tuned car very quickly. Like mark has said, dont worry about it, put the chip in (assuming its for the correct motor (vanon vs-non vanos) and enjoy.

NOTORIOUS VR
09-14-2007, 02:38 PM
although there is always a risk when changing the engine management... the other thing is, do you know if your fuel injectors are good? hows the spray pattern? do they all flow the proper amount and within a specific % of each other? All these things become more dramatic when you modify something.