Tell me what you think of my S52 dyno graph

[Sh3rpak!ng]

Dyno was done on a dynapack at AU tuning in Huntington beach. It was 85 degrees and fairly dry.

Specs: fresh S52 rebuilt by me - started with a 2.8 block and bored to S52 spec and built with all S52 internals and everything new. Only change are copper o-rings

M50 intake manifold, MMW OBD2 ecu, KAmotors CAI, 11lb flywheel, 2.5" exhaust with OBD2 headers

I am wondering what you guys think. Torque line looks pretty choppy to me early on. This graph was generated with the raw data from the Dynapack so I could make it look nice in excel. I have data for each individual RPM point. I don't know why the guy started at 2k rpm and let off at 6500... I told him to go to 7k

Regardless, I am pretty happy with the results, though I don't like the power drop after 6k rpm. Is that normal? (are cams the answer?)

[digger]

a little leaner than optimal upto 4200rpm and after 6000.

lots of small dips and troughs at the bottom end...might just be this type of dyno and the sampling????, the power dropoff is not drastic, seems normal

[Sh3rpak!ng]

a little leaner than optimal upto 4200rpm and after 6000.

lots of small dips and troughs at the bottom end...might just be this type of dyno and the sampling????, the power dropoff is not drastic, seems normal

yea I know it's a tad lean.. is there anything I can do for that besides messing with the tune?


I have no idea why there are dips like that. In third gear with moderate throttle I can feel the car surging ever so slightly which correlates to those dips and within that rpm range. It's really weird. Pretty much everything is new...

And as far as power dropping after 6k, I guess that's normal as you said. I just didn't realize that... been a while since I drove an NA M/S52. Will some aggressive cams wake the car up in the top end?

[mpowerful]

Im interested to see what dave markert says. My guess is the tune he gave you on ecu is a touch to lean (doeant account for cams or m50 manifold). Should make a few more whp with some fuel.

[328ijunkie]

Bleh. Shoot me your address and I'll send you a cable. Your vss is either dead/dying as well cause your vanos is shutting off way too early.. (~4k dip). Easy fix.

As far as the afrs go, at my Dyno even I have trouble perfectly trusting the afr number itself sometimes depending on how it's 'rigged' into the exhaust. The profile looks great except for up top. The 'ideal' setup is high 13's tapering down to low 13's by redline. The taper should never reverse direction like yours does. Shoot me your addy and I'll send you a cable Monday. Not gonna promise more power or anything but I want it to be 'proper' and it's not right now.

As far as the dips go from 2-4k, kinda normal if you check my Dyno library. Basically the air is doing some crazy shit when the vanos is on with the m50 manifold and aggressive (s52) cams. Only times I see it and some cars are worse than others. Particular exhaust setups seem to exacerbate the problem.

[Sh3rpak!ng]

Bleh. Shoot me your address and I'll send you a cable. Your vss is either dead/dying as well cause your vanos is shutting off way too early.. (~4k dip). Easy fix.

As far as the afrs go, at my Dyno even I have trouble perfectly trusting the afr number itself sometimes depending on how it's 'rigged' into the exhaust. The profile looks great except for up top. The 'ideal' setup is high 13's tapering down to low 13's by redline. The taper should never reverse direction like yours does. Shoot me your addy and I'll send you a cable Monday. Not gonna promise more power or anything but I want it to be 'proper' and it's not right now.

As far as the dips go from 2-4k, kinda normal if you check my Dyno library. Basically the air is doing some crazy shit when the vanos is on with the m50 manifold and aggressive (s52) cams. Only times I see it and some cars are worse than others. Particular exhaust setups seem to exacerbate the problem.

Thanks Dave, you are seriously the man. I didn't post this looking to guilt you into helping or anything but I sure do appreciate it. Good customer support right there. You'll have more of my business in the future. PM incoming.

I feel a little stupid, but what's the vss? vehicle speed sensor? as in the one in the diff?

Not sure how accurate the afr is, I didn't have a bung in the exhaust yet so the guy at the shop put a pipe/probe into the muffler to read it (I don't have cats). And yea, I'm not expecting more power or anything at this point so no problem there.

I'll take a look at your dyno library again to re familiarize myself with the s52 typical graph. It's been a while. I'm also considering an entire new custom exhaust from headers back and incorporating some better design in line with a lot of exhaust/header research I've been doing (euro headers, appropriate length secondaries and merge/x pipe etc.)

[Northern]

but what's the vss? vehicle speed sensor? as in the one in the diff?

You got it.

Even if your dyno is the tiniest bit off, it still makes my M52 jealous.

[328ijunkie]

Not helping for guilt, I want MMW ECU guys to have the most powa! ;)
Wheres my PM/Email ;)

[Sh3rpak!ng]

Not helping for guilt, I want MMW ECU guys to have the most powa! ;)
Wheres my PM/Email ;)

Hehe I'm fine with that! Sorry I just realized I got side tracked yesterday and I never sent it.


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[Sh3rpak!ng]

You got it.

Even if your dyno is the tiniest bit off, it still makes my M52 jealous.

The vss makes a difference for vanos operation? I had no idea. Kinda makes me wonder if I properly connected that wire when I was building the harness. Now you got me paranoid.

But yea, I was pretty happy after that dyno! Wasn't expecting that much powa!!


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[Sh3rpak!ng]

Wheres my PM/Email ;)

Pm sent!


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[2mAn]

You got it.

Even if your dyno is the tiniest bit off, it still makes my M52 jealous.

Get S52 cams then...

edit: Charlie, Im curious how your break in was? Mine had less than 50 miles on it after the rebuild and then I drove mine 1200 miles from Seattle down to SoCal and I was hammering it soon after I was on the road. With less than 1000miles on the fresh rebuild it was already taking a beating. I have nearly 30k miles on my rebuild

[Sh3rpak!ng]

Get S52 cams then...

edit: Charlie, Im curious how your break in was? Mine had less than 50 miles on it after the rebuild and then I drove mine 1200 miles from Seattle down to SoCal and I was hammering it soon after I was on the road. With less than 1000miles on the fresh rebuild it was already taking a beating. I have nearly 30k miles on my rebuild

Whoops, missed your edit.

I followed the "hard" break in procedure outlined by mototune which also seems to be supported by a couple of the piston ring manufacturers. Basically just hammering on it for the first 150 miles. I did like 3 oil changes at 20 miles, another 50 miles and then like 150 miles and then 1k miles with dino oil then switched to synthetic. Now running shell rotella t6. So basically I was hammering on it from the start. And continue to hammer on it daily. Probably around 5k on the swap now.

[Sh3rpak!ng]

derp

I don't think I ever connected the vss signal wires for the DME, hence the "dead or dying". Confirmed that mistake with a wifi dongle connected to my iphone running dashcommand. 0 mph at any speed My LTFTs were also 0 which I assume is because my ECU doesn't think I ever move the car!

Can anyone confirm for an obd2 e36 M3 manual harness the relevant wire is at pin 9 (brown with red stripe) on the x20 connector and it should be connected with pin 14 (black with white stripe) on the e30 c101 connector?

I am going to peruse the ETMs shortly to trace the wire straight from the e36 ecu to be sure

dammit I feel like a dumbass. I figured if I didn't throw a code for that initially it wasn't a problem... I should've done some monitoring earlier but was waiting to wire up my 20 pin connector into the glove box which I still haven't done.......

[King Mufasa]

Put back the s52 intake!!