Engine Engine number 9? Wait, Power to weight?

[moatilliatta]

Id love to do an N52/3 if they could be done for the same power to weight.

Right now my E30 is around 2900 with me rounded up. EGH. S50, but S54 ITB and oil pan adds weight, Ill call it ("S53") The end goal and final vision was to have all S54 and 350WHP.

Thoughts?

S54 - 2XXX - 350WHP
S53 - 2900 - 300WHP 9.6:1
N52- 2XXX - 3XXWHP

I'm not really sure how weight a S54 would add. but I assume


S52 - 435lb
"S53" -460 - ESTIMATED
S54 - 475lb
N52 - 330 LB


Would the N52 really be 130 LBS lighter?

Hit me

[digger]

depends what it's for skids or track

[moatilliatta]

Track.

[varg]

I've never seen good concrete representative weights here for anything but M20 and M42. Did anyone publish any concrete numbers that show the assembly/dress state of the engine in a comparable way, particularly the N52? S52 should be very close to M50 weight, crank is heavier (sorry, I never weighed my S52 crank when I was building the M50B30), blocks are basically the same minus the material for the bigger bore from what I've seen. IIRC S54 bare block is within a couple of pounds to M50/S52 but again the crank is a bigger and heavier unit and the head going to be heavier by its complexity and dual VANOS. Let's take some concrete numbers for now: M52 AL block is 51lbs lighter than M50 iron block: https://www.r3vlimited.com/board/for...n-block-weight https://youtu.be/J_VPIYUKBZY?t=910 . How much lighter can an N52 block be when an M52 block already weighs a mere 54-56lbs? There's an oft quoted forum wisdom of the block alone being 22lbs lighter than an AL block, by which I am guessing they mean M54. That's suspicious to me, they mean to tell me they cut the weight of the block by 40% by using some magnesium and better design optimization? Doubt. Based on what I've seen here, if I had to bet on how much lighter an N52 is than your "S53", I would say under 100lbs difference. I can see the block being 65lbs lighter tops, the head maybe 5lbs lighter, and the crank 10lbs lighter. The rest of the stuff (ITBs, valve cover) doesn't net the extra 50lbs necessary to make that 130lb figure imo.

The only N52 weigh-in I've seen is here: https://www.r3vlimited.com/board/for...ts-guide/page3 and it's only 39lbs lighter than Vorschlag's fully dressed M20 weigh-in while stating nothing about the accessory state, only that the exhaust manifolds are missing and the transmission is "lighter".

[digger]

Track.

high speed tracks or lots of straights s54 but 350 is FBO stock is like 270-280 not exactly cheap given needs mild cams, airbox, proper header, tune etc.

tight twisty slow tracks I'd rather the lighter setup personally

[hoveringuy]

Would the N52 really be 130 LBS lighter?

Hit me

You betcha! I weighed my motor WITH transmission at 458 which is less than just S54. I could simulate an S54 with two freakin' sacks of concrete on my hood.

My car is 2400# with full tank. My tires last longer, brakes work better..I take my cue from the Miatas that are not that powerful but still lap pretty quick.

high speed tracks or lots of straights s54 but 350 is FBO stock is like 270-280 not exactly cheap given needs mild cams, airbox, proper header, tune etc.

tight twisty slow tracks I'd rather the lighter setup personally

That's what I'm aiming to find out, top-end power or usable torque? With the N54 manifold I made awesome power, particularly on the top-end, but most of my acceleration is out of corners and only some is drag racing down the straight (where I walked a Challenger SRT...)
The N52 intake will give me more area under the curve to the left; how will it translate to lap times..?

How much lighter can an N52 block be when an M52 block already weighs a mere 54-56lbs? There's an oft quoted forum wisdom of the block alone being 22lbs lighter than an AL block, by which I am guessing they mean M54. That's suspicious to me, they mean to tell me they cut the weight of the block by 40% by using some magnesium and better design optimization? Doubt. Based on what I've seen here, if I had to bet on how much lighter an N52 is than your "S53", I would say under 100lbs difference. I can see the block being 65lbs lighter tops, the head maybe 5lbs lighter, and the crank 10lbs lighter. The rest of the stuff (ITBs, valve cover) doesn't net the extra 50lbs necessary to make that 130lb figure imo.
.

Everything on the motor is lighter. Aluminum bolts. Hollow camshafts, but it also has two additional electric motors (VVT and coolant). I had an N52 block at the e30 picnic and was asking people to pick it up. Kids were pressing it over their heads.

[hubcapboy]

I love this conversation because it can only end with you deciding on an N52. It’s the most advanced and lightest 6 cylinder naturally aspirated engine that BMW ever made. That’s all you need to know.

The swap is only hard now because of the oil pan. We’re working (slowly) on making the oil pan easier.

[hoveringuy]

I love this conversation because it can only end with you deciding on an N52. It’s the most advanced and lightest 6 cylinder naturally aspirated engine that BMW ever made. That’s all you need to know.

The swap is only hard now because of the oil pan. We’re working (slowly) on making the oil pan easier.

That, and these motors are still available. When was the last S50 sold? almost 20 years ago? S54's are becoming rare and expensive. My 64,000 mile N52 was $1800 and there's TONS of them around.

(and they don't leak)

[hubcapboy]

The only N52 weigh-in I've seen is here: https://www.r3vlimited.com/board/for...ts-guide/page3 and it's only 39lbs lighter than Vorschlag's fully dressed M20 weigh-in while stating nothing about the accessory state, only that the exhaust manifolds are missing and the transmission is "lighter".

Keep clicking through - that’s my photo and my driveway. I said in the original post it was fully dressed and ready to run other than the manifold.

Edit: I even re-mounted the AC compressor for the weight.

[digger]

Keep clicking through - that’s my photo and my driveway. I said in the original post it was fully dressed and ready to run other than the manifold.

Edit: I even re-mounted the AC compressor for the weight.

so how much do you estimate was missing?

[hubcapboy]

so how much do you estimate was missing?

I don’t understand the question. Weight or components?

[digger]

I don’t understand the question. Weight or components?

Weight 10lb, 20lb ?

[varg]

So all of this above... An N52 and transmission with no exhaust manifolds and engine mounts weighs 462lbs. A dressed M20 with exhaust manifolds, engine mounts, oil in it and transmission weighs 476lbs. Safe to assume that the engine mounts and manifolds will close that 14lb gap easily... Easy to say that with an N52 you retain about the original balance of the car but with more power and torque all over. It does seem like a pretty sweet swap.

I had an N52 block at the e30 picnic and was asking people to pick it up.

Did you weigh it??? We're dying to know what it weighs since we already know for a fact that an M50 block is 103-108lbs and an M52 AL is 51-57lbs by the two bare block weights we have above.

Kids were pressing it over their heads.

Kids, or "I'm getting old so I call 21 year olds kids now" Kids? I am guilty of the latter too I know I can overhead press more than an M50 block, but it's an odd shape so it would probably be awkward to press.

[moatilliatta]

Six speed gearbox is about 25lbs heavier?
We could say both are single mass flywheels?

I agree area under the curve matters also, Any whether S54 or N52, Dual vanos is leagues above singe.

[hoveringuy]

Did you weigh it???.

No, compared to an iron block it was like a big piece of styrofoam

I know where to find it and will work on getting a weight

My guess is based on a 52lb Al block, and if its 60% Mg and Mg is 33% lighter than Al, that means 40 lbs+/-

Agree that overall, even with the heavier transmission and dual-mass flywheel (but no A/C) Im probably 20lbs lighter than an M20.

Also worth noting that Magnesium is awesome at damping and with the bedplate crank it doesnt have the nasty harnonics of Al blocks.