Dyno plot of s50 swap

[TWRViper]

Hey guys,

I need some input on my dyno plot from my s50 powered 1986 325.

Mods:
-Supersprint headers
-high flow cat
-dynomax muffler
-aluminum flywheel
-AC removed
-PS removed
-K&N filter

Dynoed on a Mustang dyno.


Note: The RPMs were back-calculated from MPH since we did not have a good place to read RPMs. The RPM migh be a little off.

Here are the issues:
1. I notice that my rev limiter is at 6800 RPMs (according to my tach). I heard the the revlimiter for the e36 325 is at 6800 while the e36 m3 should be at 7000. Could some one confirm this? Could I be running a 325i ecu rather than the m3 ecu?
2. I don't like the 11.7 A/F ratio valley at 5700 RPMs. Shouldn't it be stay between 12-13 for a stock ecu? The A/F ratio seems to lean out way too fast after 5500 RPMs.
3. I think my fuel pump is stock. Do I need a new fuel pump to provide more fuel for the increased demands of the s50?

Thanks
Tom

[cheades]

Shouldn't need a fuel pump until you go for a lot more power, have you changed the fuel filter? How about the spark plugs, do you remember what ecu number you were running when you installed it? Try getting a chip for it, they aren't every expensive and make a nice difference.

[Mike B.]

11.7 is rich, not lean - your fuel pump is just fine.

Do you have the speed signal wired? That can affect your rev limiter if it is not set up properly. Can you see on the dyno when the VANOS kicks in?

[FredK]

I can't see the graph. But if it enriches the mixture to 12 all the way to redline, then you probably have a sensor problem. Did you install a new O2 sensor when you did the swap?

[TWRViper]

Try right clicking on the picture and click "show picture". If that doesn't work here is a link. http://pg.photos.yahoo.com/ph/twrvip...e2.jpg&.src=ph

Hopefully the graph will work. You will see a valley where the A/F ratio hits 11.7 (rich). Then leans out very fast after that.

I did not do the swap. So I don't know if the speed signal is wired. Are you refering to the crank hall sensor (which is installed)?

[aeryk7]

If you didnt break 200whp than there is a problem and with the mods you have i suspect you might have a modded m50 on your hands but i could be wrong . I am pretty sure that 205 whp is the lowest you wil see on a stock
S50

[TWRViper]

Can you see the graph?

Keep in mind that this is on a mustang dyno which calculated HP by applying load rather that sensing inerta. Load dynos tend to read 10-20% less than Dynojets which are inertia dynos.

I am pretty sure that it is a s50 engine. I question whether it has a m3 ecu because of the revlimiter is at 6800 rpms and maybe the fuel filter is plugged. Anyone with some insight about this?

When does the VANOS kick in?

[FredK]

OK, I can see the graph on the direct link. On a Mustang, those numbers seem OK. However, I'm with you, I don't know what that valley is all about. You can definitely get some power back if you resolve it. Are you running any software at all?

[TWRViper]

I don't think that I have a chip. It should be stock. From looking at other dyno plots it seems that other stock s50s are running a AFR of 12-13 throughout the rpms. Is there ANY possibility that I mighbe getting those numbers with a e36 325i ecu or a m3 ecu with 325i chip?

[aeryk7]

Can you see the graph?

Keep in mind that this is on a mustang dyno which calculated HP by applying load rather that sensing inerta. Load dynos tend to read 10-20% less than Dynojets which are inertia dynos.

I am pretty sure that it is a s50 engine. I question whether it has a m3 ecu because of the revlimiter is at 6800 rpms and maybe the fuel filter is plugged. Anyone with some insight about this?

When does the VANOS kick in?

I question the engine because you basically are telling us the cats are removed , you have headers and intake , but your are dynoing under stock s50 numbers

VANOS kicks in at like 3500rpms

If you were running 325 software the car will detonate(ping) atleast what i am told, and i believe when i used 325 software to start it once my car ran rough.

Alright first of all you need to figure out what ECU you have example 413 or a 506. Second if you have a 506 you are running a stock m3 chip unless its been replaced with a performance one, if you have a 413 and the chip hasnt been replaced with an m3 chip than you are running 325 software.

[Addissimo]

If you didnt break 200whp than there is a problem and with the mods you have i suspect you might have a modded m50 on your hands but i could be wrong . I am pretty sure that 205 whp is the lowest you wil see on a stock
S50

I'm with this guy-

It looks like a lighty modified m50 or m52 using an m3 ecu with a bad o2 sensor.

How is it running off of the dyno? Idle quality? What is the warm up enrichment like? It could almost be a bad water temp sensor not letting it get out of that cycle... I donno though. That vally is odd.

[TWRViper]

Thanks aeryk7 that is what I needed to know about the ecu. I will check the ecu tonight.

I don't think I have low compression, but I might as well check just to be sure. This car runs amazing. It is very quick and feels great. I just got back from driving it on a 700 mile trip where I got 28 mpg highway.

I raced a gutted e36 m3 with underdrive pulleys, chip, and exhaust. I had full interior (spare and such) so I think our weights were the about the same. We raced from 25-135mph. He started to inch away at high rpms at at high speeds 120+mph.

I also drove another completely stock e36 m3 (though I didn't redline it). Mine was definately quicker. I am pretty sure that a m50 would not have done that well.


I feel like 6000-6800 rpms has no pull and rev limiter kicks in early at 6800. Ths resent dyno pull confirms my suspision how I am running lean at high rpms. Any thoughts?

Thanks

[aeryk7]

I would go back and get dynoed again , tell them to get rpm reading off of any of the coil pack harness connecters. Also make sure you dont have a check engine light on.

[TWRViper]

FYI This is the car that we are talking about. http://cgi.ebay.com/ebaymotors/ws/eB...RK%3AMEWA%3AIT

I have all the receipts. From the swap, which was professionally done.

From my memory there are three wires going to each coilpack. Which wire should I get signal from?

Thanks

[SpunkyE30nOk]

e36 m3s redline at 6800 with a fuel cut at 7 grand i believe...if u have a performance chip i think it just moves the redline to the fuel cutoff at 7000 or gives u a couple extra hundred rpms to play with