Just been to dyno my car. The current list of mods is US Spec 3ltr M3 cams, Big bore Throttle Body, Decat, M3 Backbox and a fart valve. On an M50B25
And the dyno shown 172.8 HP :frown The fuel map shown that the car is running wayyyyyy too lean! And it is very very lumpy. Has a massive dip at about 4.8k revs and the max torque is 166 ft/lb.
Rather pittyfull to be honest. Altho the peak was at 6080 rpm
Any suggestions? But the AFR is rediculas. It goes up to 15.2 at 2500rpm and then drops all the way to 13:confused
Will upload the pics of the graphs a bit later.
you should be seeing way more bhp with those mods. i got ~170WHP, and that's without the bbtb and m3 cams. on stock injectors. regarding the injectors, i just swapped my stock green 325i injectors with pink ones (328i). runs great, but the idle is a bit rough-ish. so, if they work good on my car (without the cams), on yours i'd say it's a must. regarding the OBD, you can do it yourself (with the "stomp test", as in US spec e36), you just need to wire one pin from the x20 connector to the CEL in the instrument cluster. not that hard, i did it in 20 minutes. prob is, you might not be able to get your codes unless you have either a proper chip (non-pirated, ebay version), or a stock ecu that you can run especially for the diagnose.
i would check the fuel pump, the fuel filter and the injectors on that. for comparison, this was my AFR at that time, on stock injectors. now should be richer.
Thanks for the info mate. What pin needs to be wired up? And where do I wire it to the Check Engine Light? Will I be able to get the error codes throught the Check Engine Light that way? Its worth a try:thumbsup
To read codes for an OBD I car, you start by turning the ignition key on (do not start the engine) and pressing the gas pedal to the floor five times within a period of five seconds. If you proceeded correctly, then the check engine lamp will light on for five seconds, then blink off, then blink on for 2.5 seconds, and then go off for another 2.5 seconds.
After this, the computer will start to show you the trouble fault codes that are stored.
The codes are given by short flashes of the check engine light, followed by short pauses. The codes are all four digit numbers. For example, the trouble fault code for monitoring the battery voltage level is 1231. This would show up flashing as "flash - pause - flash - flash - pause - flash - flash - flash - pause - flash." I suggest having a pen and paper handy when you do this, as the codes have a tendency to flash faster than you would think.
If there is more than one fault code stored, then each code will be separated by a 2.5 second pause.
When there are no more codes to be read, the computer will give the code 1000, which is one short flash, and then the light will remain off. Then the check engine light will flash a half-second and then turn off. To read the codes again, simply turn the ignition key off and on again and repeat the procedure with the gas pedal (five times within five seconds).
To erase the fault code memory, first make sure fault code 1000 (short blink and then light goes out for long period) is present, then depress acellerator fully for at least 10 seconds. Read fault codes and check for 1444 code (no faults stored).
Right, decided to have some therapy after my yesterday's exam and put the injectors in last night.
Put them in and my mate gave me an FSE adjustable fuel pressure regulator so I could try and up the fuel pressure abit. Got it set at 3.5 bar on full throttle and drove the car last night. Does not seem to be that much faster then it was:frown Just seems alot smoother and the terrible flat spot that I had at around 4k revs is gone.
Going to go and wire up the Check Engine light as said by mistreku so will be back with results of that later.
Now just a question while Im doing all that. Have I got the fuel pressure set right? I thought that since the stock fuel regulator is 3.5bar max, then it be best to set this one up at this pressure. Any ideas?
you could try raising the pressure little by little, until the idle starts to be less smooth. then give it another go, and lower the pressure if necessary. and one other thing you could try: disconnect the lambda sensor and go for a test. see if anything changes. keep us posted!
Right. Sorry for taking so long but been out with the lambda sensor disconnected and it seemed to go well but not 50 bhp faster.
Then had the lambda connected, disconnected the battery. And wired in the Check Engine Lamp. The Foot test works a treat. At first came up with an error code 1221. Then errased it and checked again after running the engine. The code went. Then took it for a drive and got a code 1222. Erased that again, drove it and now Im getting an error code 1215. But the engine seems to idle fine. Would the fact that I put on a big honking Green Cotton filter matter? Got the filter strapped to the MAF.
Could something like an air leak at the inlet manifold do this?
At the moment the Im running the fuel pressure at 4bar max and the bottom end torque seems to have came back.
right.. 1221 was because you d/c the lambda. 1222 prolly because car is running a bit richer than its parameters, due to the FPR. so no worries here. now, i would worry a bit about that last code, which is the MAF. either it's on it's way out, or the error could be an air leak as well. i think best thing would be if you had another MAF to borrow from someone, and see if it changes anything. and also look for air leaks, especially the intake boot, where the 2 hoses connect. they tend to split. although, if there was an air leak, i think the idle would be rougher. but it's worth checking, as it's free.
if you were any closer, i would've helped gladly with test parts from my car.
p.s. glad you sorted your obd! :thumbsup
l.e.: i just realized you said air filter strapped to the maf. although i doubt that will flash an 1215 code, it will decrease performance pretty drastically, because of the heat soak. if you still have the oem box, put it back on, erase all faults and give it another go. i pretty sure you'll see some performance improvement. for the air filter, you'll need to bring it closer to the headlight and put a heat shield on, otherwise it's not such a great mod, you'll end up losing good power. not 50bhp, of course, i'm sure this is not the major prob, but i think it's one of them.
Ah. I see, will put the old air box back on and have another go tomorrow. Is it possible that one of the o rings could leak the air from where the inlet manifold joins to the cylinder head? And I had some problem with idle when I first started the car with the M3 cams but after couple hours of belting it throught the north yorkshire dales with a 100 mile bed in down the motorway, it was fine and dandy.
Would you be able to confirm that mods such as US M3 cams, decat and bored out throttle body would not need a remap? As I'm still running the stock ecu.
The guy who dyno'd my car, said since it ran too lean, the ecu would not let the timing to advance fully. Now it runs lovely and rich but not flooded. Can actually smell a bit of petrol from the exhaust. Could it be something to do with the Vanos or the O2 sensor?
lol, i thought you already had it chiped. you defo need to get a chip for your mods. all your mods tend to get a lean afr. the fpr improved the mixture somewhat, but you definitely need another soft for that. vanos has nothing to do with top end power, only mid-range power/torque. o2 sensor i'd say it's good as well, since it didn't make any major difference when you d/c it.
Ahh, that explains alot then. I think in that case I will try and sort the error codes out that are on at the moment and leave it till the engine comes out for a pre-Turbo rebuild:rofl
if it's your daily driver, i would recommend a S/C, rather than turbo. i think it's more reliable and definitely easier to drive. not as powerful as a turbo, though, but should be enough. and you won't need an engine rebuild. regarding the chip, i've been talking to a guy from germany, who does chips. i couldn't strongly recommend him, i haven't bought anything from him yet, but he seems to be all right. he sells his chips on ebay, but he also has a physical address, unlike most ebay chip vendors, with dyno and everything. i know usually ebay chips are crap and everything, but for £50, i'd give it a go. maybe he can sort you out with a chip for your mods. lemme know if you want his email.
I been thinking about this alot and with a bit of pointers from gstuning, I have decided with the turbo route. Im building the car as a drift monster and it would mainly be driven on weekends as I have a second car sorted out which is a bit of a jigsaw puzzle :hihi
Since my shell has been sideswiped before I bought it, It has been done right, the body has been straightened properly but I just would not want to put too much power through it. I bought a 323 coupe for 700 quid with 90k on the clock:thumbsup:thumbsup
That shell is in mint condition, the arches are just starting to rust so I can get the whole body work sorted out.
And then here it comes. My M50 lump is coming out for a rebuild and a turbo and. The M52 engine before hand is coming out from the 323 and getting serviced and going into my current shell so I have to worries for a year.
Then once the 323 shell is ready and the M50 engine is done, the M50 is going into that and the my old shell with the M5s engine is going to be a runabout.
Hope this makes sence:hihi
still going on the road :thumbsup gona be a little sleeper. Im leaving the standard bumpers on. Not going for M-tech stuff, Just the M3 rear wing and going to see if I can get a stealthy front splitter or will make one :hihi And yep, one of the people I look for car look inspiration has to be the one and only Chip Foose :thumbsup
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