N52 Swap Discussion

[Caperix]

I've seen a few n52's slip timing, usually due to a locked up AC compressor or a failed tensioner causing the belt to bind. I have never had one suffer engine damage from this though, just replace the crank bolt & re time the engine. Manual transmission cars use an extra friction disc in the front crank hub to help with preventing slip from a rough down shift.
On the n54 manifold, I have read e90 posts that say the port match is not perfect & if you smoke the intake they leak, have you noticed this?

[nando]

I've never heard of that.

[MWC]

Does the N52 have issues with the timing chain on track? I’ve heard the chain can skip if you slightly miss a downshift etc. Is this true?

[nando]

yeah, you're never getting 350whp out of an N52, without boost anyway. I think 285-300 is doable. Is it worth it? I'm not sure. I didn't even bury Steve's car and it was pretty fast for me, lol.

Yeah, sound is definitely part of it too. I'm just saying, the N54 manifold works, but it's not exactly ideal. What it really has going for it is cost, you can get them for like $20. Maybe I'll try that CF Nylon filament and 3D print my own.. lol

[hoveringuy]

It's not an S54, never will be. The S54 is a phenomenal motor.
it's also much more expensive, heavier, and a bit of overkill for me
I could seriously add +100hp to my car and only be a tiny bit faster. I'm only at full-throttle on the long straight and most everything else is handling/braking, where the light weight helps tremendously
OIl control with the cosworth flaps in the oil pan baffle is superb!

Yep, MILV would bump me another 15+/-

[moatilliatta]

Considering we were seeing 285 at one point at 7200 the N54 manifold may not be ideal, but I can't imagine getting much more power out of an NA 3.0, particularly with only 9.9mm of lift That's somewhere around 110hp/litre.

+1MM if you run a MILV?


Id be interested if I knew I could get same power to weight at a 350whp S54, And proper oil control with slicks at the track..

[hoveringuy]

The biggest benefit to the N54 manifold is it's cheap, it bolts on, and it functions well while giving you more space in the engine bay. If it was literally the best manifold you could have on an N52, that would be a pretty big coincidence!

Considering we were seeing 285 at one point at 7200 the N54 manifold may not be ideal, but I can't imagine getting much more power out of an NA 3.0, particularly with only 9.9mm of lift That's somewhere around 110hp/litre.

My beef with the N54 manifold is that it's massively ribbed to hold boost and the TB has a weird tilt to it

Now, the sound of individual horns would be worth it.

We need a few more N52 swapped e30's and some adventurous souls to develop it...

[nando]

The mechanicals of valvetronic basically never fail. Sometimes the eccentric shaft sensor gets oil in it, and stops reading, so the DME sets the valves to full lift and uses the throttle instead. Rarely the motor itself fails, but that is usually from improperly removing it without setting it to the service position, which can break the shaft or chip the gears. The rockers and levers? They seem to last literally forever.

You could just cut off the trumpets of a stock N52 manifold and run it. It would work. You could put any plenum you wanted over it too. But if the eccentric shaft sensor fails you're going to be full WOT with no way to control the engine.. that's the rub.

So if you put the S54 throttles, whatever trumpets/plenum you want, you basically get the "open stack" design and keep the fail safe functional. It also helps that they are almost the perfect size for the N52 intake ports. :)

[moatilliatta]

What about just a cut off intake runners coupled to an S54 airbox?

Most valvtronic failures are intermediate levers? Maybe a broken gear on the adjuster here and there? Just saying probably more chances of internal failure than needing a fail safe.

Ie early M54 / M52tu cars had electric and cable throttle. Most the times the rubber on the throttle cable fell apart and caused issues more than the throttles. Early M54 had harness throttle issues..

but... not a fan of open trumpets in a hot engine bay. Just ideas.

[nando]

No, throttles are probably not faster than valvetronic. At least not in a way that you'd notice. We had the throttle response tweaked to high heaven, it was actually too sensitive.

But, I do think there is potential with ITBs - but not because of the throttles specifically. the N54 manifold does work, but mostly because it just happens to bolt up. It's not like it was designed for this use either. ITBs would effectively allow you to run "without a throttle", which is also physically possible, but there'd be no fail safe. Otherwise you could just run open trumpets or add a plenum and use no throttle at all. So S54 throttles would allow you to run trumpets, either open or with a plenum, and still have a throttle backup (they stay open most of the time on the N52 anyway).

You could also command the valve lift to 100% all the time and run it on the throttles but I'm not sure what that would drive like. When people talk about S54 throttles on an N52, I don't think they're talking about using the literal throttles to control the engine. At least they don't understand how it works if that's the case. The throttle is only there for idle and startup, and for a failsafe if something happens to the valvetronic system. The rest of the time it stays open.

The biggest benefit to the N54 manifold is it's cheap, it bolts on, and it functions well while giving you more space in the engine bay. If it was literally the best manifold you could have on an N52, that would be a pretty big coincidence!

[moatilliatta]

I don't have a TPMS. I'm typically 29psi cold and 35hot. Oil pressures? If the light stays off I'm happy. (hasn't ever flickered even a bit)

I'm not sure an ITB would dyno anymore than the N54 intake, not even sure they would really work right unless you locked the Valvetronic to full lift. N52 already has ITB of sorts in the valve lift.

Sorry. Which tires are you running. What are you doing for oil pressure monitoring?

If only direct injected… ITB - Valve lift..

But throttles have faster response than the valvetronic?

[hoveringuy]

hoveringuy, what are you running for tire/ oil pressure monitoring?

I see rabid racing development is in the works for S54 Itb kit on an n52.

What do we think these will dyno?

I almost want to scrap my S54 iteration 2 motor in my E30…
be nice to cancel out 75lbs ~

I don't have a TPMS. I'm typically 29psi cold and 35hot. Oil pressures? If the light stays off I'm happy. (hasn't ever flickered even a bit)

I'm not sure an ITB would dyno anymore than the N54 intake, not even sure they would really work right unless you locked the Valvetronic to full lift. N52 already has ITB of sorts in the valve lift.

[moatilliatta]

hoveringuy, what are you running for tire/ oil pressure monitoring?

I see rabid racing development is in the works for S54 Itb kit on an n52.

What do we think these will dyno?

I almost want to scrap my S54 iteration 2 motor in my E30…
be nice to cancel out 75lbs ~

[hoveringuy]

Update! The track event last month was a complete cluster-fuck. I couldn't get more than a few laps without someone blowing an engine or spinning into the berm to bring out the black flag. Nothing worthwhile came from it.

Today, however, was awesome!

First, the larger PS pulley and 100bar regulator are clear winners! After several 30 minute floggings the PS temps were well below the 275 temps I saw earlier in the season, all the way down to 215. A cooler won't even be necessary.
Best of all, steering feel is much improved, great feedback in the corners now. Highly, highly recommend. I will call this sorted.

It was essentially an open track day, running port and starboard 30 minute sessions. I got over 100 miles in before lunch over several long sessions and the motor was flawless. No hiccups, burps leaks. Nothing.

I had also upgraded to a 3.25LSD with a 3-disc clutch pack and it was A-Ok. Great fun to play with exiting the corners, and what surprised me the most is how much better the braking became. No more dancing around under heavy braking, it tracks straight and true now even when braking hard on uneven pavement. Nice!

Unfortunately, I needed to limp home after lunch because of a cracked brake rotor.

Coupla good stretches where I'm drag racing an E46 M3 here.... https://www.youtube.com/watch?v=dvRmVAqjZ14

[hoveringuy]

[LIST][*]In a race car it would be ideal to have the fuel pump hot wired to it's own switch. Is the EKP necessary under these circumstances? I.e. does the ECU need the EKP present to function properly?
!

It couldn't care less about the EKP, the command to turn on the fuel pump is sent "in the blind" (ECU never gets an acknowledgement).