Can someone explain this shitty dyno graph? (m50, s50 cams)

[JGood]

Had my car dyno'd today. m50, s50 cams, A chip I was told was made for that setup, 2.5" exhaust and headers, cone filter intake. Why do I have less low end power then an m10, and the same peak power as a stock m50?

My buddies OBD-1 S52 with a TRM tune dyno'd 242whp right after mine.





And here's an overlay, the black line is from a dyno from another guy with a similar setup (http://www.r3vlimited.com/board/showthread.php?t=150491)







Three things come to mind.

1, the chip. Could it cause me to be down ~25hp through the entire powerband?

2, Cam timing. I'm pretty sure I did it correctly, I was able to turn the sprockets through their full range of motion after installation, and installed the vanos with the sprocket turned the whole way, and engaged on the first possible tooth. I also have the Beisan seal kit.

3, Mileage. This motor runs great, gets good gas mileage, doesn't burn or leak anything. But, it has 250k miles.

[Danny]

You sure they're s50 cams?

[JGood]

You sure they're s50 cams?

Yep, went through a crappy process where I was sent m50 cams the first time around. I learned how to measure cams, got to use some expensive tools, and verified the new ones are s50 cams.

[JGood]

I just looked, it makes less power then my stock m20 below 5.5k

[hoveringuy]

Need to see the A/F line on the M50.

[dkbmxer002]

yeah... did they not hook up an a/f ratio?

[e30polak]

Did you time them properly?

[White325is]

Damn, My stock S50 put down 260rw on the same dyno..

[JGood]

Did you time them properly?

See first post...

2, Cam timing. I'm pretty sure I did it correctly, I was able to turn the sprockets through their full range of motion after installation, and installed the vanos with the sprocket turned the whole way, and engaged on the first possible tooth. I also have the Beisan seal kit.

Need to see the A/F line on the M50.

yeah... did they not hook up an a/f ratio?

It was an extra $20, and I thought everything would be dandy and I'd put down 190+, so I didn't bother. I wish I would have.

Damn, My stock S50 put down 260rw on the same dyno..

Well, that's not normal. That's over 300 crank horsepower, stock is 240. Most stock s50's dyno ~210 on a dynojet that I've seen. With tuning and bolt-on's, usually 230-240. This wasn't at their shop, it was on a dyno trailer at a car show. I would normally just write it off as being improperly set up, but my buddies s52 putting down normal numbers right after me kinda has me worried.

[Gnarles]

Does it feel down on power?

[JGood]

Does it feel down on power?

What do you mean? It feels the way it has for the past 2 years since I put it in. I've gotten used to it. It's only 25hp or so down the whole way through the powerband, so it's not like I feel a dead spot or anything. I don't have any other m50 e30's that I drive to compare it to.

Before I did the cams, I ran a 14.4@94mph @ 2700 lbs and a 2.2 60ft. So if anything I thought I had a strong m50. After I put the cams in, my vanos went bad, so I had no power at all for a few weeks. After fixing it, I forgot what it was supposed to feel like, so I'm not really sure if it's down from stock or not (obviously it looks like it from the dyno).

[JGood]

I unplugged my vanos, it made no change at all in power, or idle, or anything.

I plugged it back in, and put an ebay knockoff chip in. The low end and mid range felt better with this chip, and the power was smoother overall. I'd say top end was about the same though. It's hard to tell in the rain... haha. However, the idle was horrible with that chip. It bounced constantly between 500 and 1000, like a had a 292 cam in an m20 or something.

Thoughts?

[Wh33lhop]

Was it hot out? Straight cone filter/heat soak? Besides that, your timing maps are probably okay, with a constant wide-range loss like that I'd guess your cam timing or AFR is off, but obviously you're in open loop at WOT so it has nothing to do with lamda control. Hmm... FPR? :-?

[JGood]

Was it hot out? Straight cone filter/heat soak? Besides that, your timing maps are probably okay, with a constant wide-range loss like that I'd guess your cam timing or AFR is off, but obviously you're in open loop at WOT so it has nothing to do with lamda control. Hmm... FPR? :-?

Nope, mid 60's. Cone filter with a big fan set up in front of the car. Engine was warmed up.

I'll check cam timing and vanos functionality. I just tested the solenoid, works fine.

[hoveringuy]

I unplugged my vanos, it made no change at all in power, or idle, or anything.

I plugged it back in, and put an ebay knockoff chip in. The low end and mid range felt better with this chip, and the power was smoother overall. I'd say top end was about the same though. It's hard to tell in the rain... haha. However, the idle was horrible with that chip. It bounced constantly between 500 and 1000, like a had a 292 cam in an m20 or something.

Thoughts?

Everytime you unplug your ECU it will take it a few drives to recalibrate the trims.