N52 Swap Discussion

[hoveringuy]

Would it continue to make power until an 8k redline? .

Yeah, this Dyno has 400 lb rollers so it accelerates quicker than it usually would, like 2nd gear on the street.

My understanding of the N52 soft limiter is that it's predictive so if revs are increasing quickly it will pull back earlier. Rev limit was set to 7750 here and it was pulling power starting at 7100-7200.
On a few pulls where we bumped the limit way up it carried power all the way through.
There wasn't ever a defined peak, just plateaued.

[nando]

Would it continue to make power until an 8k redline? I think you said it was torque limited somewhere. It's not that far off a stock S54. and this is with all stock internals...

[hoveringuy]

Update.

On the last episode, we had a pretty good track day with the MAF. Motor was running smooth even though it was a little down on power.
After another few days on the dyno, it's finally living up to all of its potential.

The baseline dyno showed that, indeed, it was a bit down on power at only 242hp/ and 227ft-lb. It had made around 270hp with no MAF (and no air filter...) and I expected to to recoup most of that, but expected a penalty for the MAF and the filter.
By playing with the timing and VANOS they were able to get it back up to 268hp and 246ft-lbs. It looks like there's a dip in torque at 2200 and 4000, but I think that the headers are just so strong at 3000 that it only appears that way. Drives great, pulls noticeably harder now and has an amazing amount of torque down low that makes me question why *anybody* would want a DISA intake on the N52.

The first chart is the before and after with the MAF.

The second chart is the no-MAF vs MAF plots, and how the MAF completely solves the ridiculous torque dip.

The chart is SAE corrected and calibrated to match Dynojet.

[nando]

My crimpers are actually pretty nice, the only real issue is ergonomics. I've probably done thousands of pins with them, but as you can imagine - not exactly good for the wrist. I know there's an updated version with better ergonomics. I kinda wish I had bought them now, although I ended up stopping making harnesses for people as it's just not worth the hassle (I got burned on a somewhat infamous S54 harness build, it hurt my wrist, and it cost me money in the end - screw it).

[wazzu70]

I'm pretty sure the crimpers I have will work just fine for those, they were like $40. I can't remember where I got them now, I'd have to dig way back. I use them for basically all the BMW wiring I've done, they work on all but the tiniest Tyco pins I've tried so far (I have another set I use for those). Actually I'm pretty sure I have some of those pins too, lol.

The generic crimpers are not perfect but its way better than just using needle nose pliers as it gets the generic shape correct. I usually make a light crimp to get the shape set and then use needle nose pliers to make sure it pinches tight enough one side at a time.

Is it perfect, no, but very close if you have patience. Also the crimping tool helps get the bends in the right place so the shape of the plier crimped pin is not too big to fit in the slot in the connector :)

Im spoiled because I have the real crimpers at work in our lab so everything else just feels like poo in comparison.

[nando]

I missed the link to the video - the engine sounds really good! although it's pretty quiet (probably a good thing, lol).

[LukeJ]

Cool video!

Congratulations on your new personal best lap time!!!

[nando]

heh, boiling the PS fluid - maybe an underdrive pulley would help that? BMW of course would put in a PS cooler. I actually have one I want to get rid of...

[hoveringuy]

Track event #3 on the N52 and everything is coming together. Event #1 I was in limp mode and way down on power. Event #2 it was making power but not smooth at all. Yesterday it was doing what it's supposed to do, haul-ass!

Some of the other issues also seem resolved. The coolant temps hovered at 190F +/- a few degrees the entire day. No oscillations or spikes. The motor will normally warm to around 205F before the MAP triggers and then it stays at 190 the rest of the time.

The cold air intake works GREAT. Intake temps just a few degrees above ambient.

Motor pulls happily from 4k to 7500 again and again...

Zero issues with oil pressure, not even a concern. No vibrations, thumps, driveline imbalance. Just smooth.

I had a puddle under my power steering rack my first event and thought it might be the rack; turns-out my PS fluid and resevoir are getting extremely hot and it had expanded out of the resevoir. So, that's one system that isn't happy with the high revs.

Other than that, I totally held my own in the advanced group. Ran a 1:38 (new PB!) in the first session and increased top speed to 133. Got passed by a GT350H on the straight, after he couldn't catch me in the corners, no shame in that. Let a bad-ass Honda Civic by that was just a cornering machine.

I'm running the 3.73 diff, and even with the 6th gear I'm turning about 3500 rpm at 80mph, so it's slightly annoying on the freeway but perfect for the track. I also have a 3.25 and I'll need to think about switching back to that.

The car goes back to the dyno today to evaluate the tune with the MAF, will hopefully find a little more smoothness and power.

https://www.youtube.com/watch?v=-uy--aNyIMg

[LukeJ]

Check another problem off the list.

Version 2.0 of the heater hot water hose is a nice touch as well.

[hoveringuy]

Hot air intake problem solved. This is a Vibrant 10952 bellmouth that fits perfectly in place of the high beam. Filter is up and above it internally, so rain shouldn't be a problem although I may add a screen.

The plastic divider is version 1.0 but seems highly effective, intake temps are just a few degrees above ambient for anything but being stopped.

[nando]

I did the first oil change and it was super-duper easy. The drain plug uses a 3/8" square drive which, conveniently, is any 3/8 ratchet wrench. No sockets required!

First, the magnetic drain plug works *great*, although I don't hope to see a pea size dollop of fuzz on it next time...

Total oil drained was just shy of 4 3/4 quarts, so with trapped oil I will call 4 3/4 to 5 quarts the capacity. I had it filled slightly below the top of the wing by around 1/4" so it would easily hold 5. I don't know if that's "good" or "bad', the M20 holds about 4.5 quarts and an M50 around 6 quarts. What's more important is that the oil control seems great, I haven't seen a flickering oil light once yet whereas I did get it on the M54 with a higher capacity.

It's probably from your custom pan. There's not really anything magnetic in the engine that should have any wear at all. Maybe the head, but I've never seen wear on the valvetrain even on engines with a lot of miles (because everything has a roller bearing).

5 quarts is probably fine - the stock sump is 7, but it seems like the first quart is mostly for safety/cooling. the 3 liter N52s don't seem to burn oil (until they get a *lot* of miles) so unless you have a bad leak the level should stay consistent. There's always that heat exchanger thing for the oil filter housing, although it is a bit ugly.

[TobyB]

even if the motor will easily spin to 8k on stock internals.

yeah, you're totally not selling this one.

t
may sell his M54 if you two keep this up...

[hoveringuy]

I did the first oil change and it was super-duper easy. The drain plug uses a 3/8" square drive which, conveniently, is any 3/8 ratchet wrench. No sockets required!

First, the magnetic drain plug works *great*, although I don't hope to see a pea size dollop of fuzz on it next time...

Total oil drained was just shy of 4 3/4 quarts, so with trapped oil I will call 4 3/4 to 5 quarts the capacity. I had it filled slightly below the top of the wing by around 1/4" so it would easily hold 5. I don't know if that's "good" or "bad', the M20 holds about 4.5 quarts and an M50 around 6 quarts. What's more important is that the oil control seems great, I haven't seen a flickering oil light once yet whereas I did get it on the M54 with a higher capacity.

[nando]

I'm pretty sure the crimpers I have will work just fine for those, they were like $40. I can't remember where I got them now, I'd have to dig way back. I use them for basically all the BMW wiring I've done, they work on all but the tiniest Tyco pins I've tried so far (I have another set I use for those). Actually I'm pretty sure I have some of those pins too, lol.