Vass

Yeah true, didn't realize which type you had until you uploaded the photos. They do a version with the bolt-in style coils too, which is slightly more expensive for some reason though - Amazon / eBay.

Awesome stuff! Love your meticulous approach. With the valve cover, haven't succumb to the impulse of buying one yet but have been contemplating one of these Mitzone aluminium replacement ones for a while. I'm bound to get one eventually, can't remember if eBay or Amazon worked out to be cheaper. Reviews and fitment seems to be decent, just need to make sure to give it a thorough clean before install. Probably cheaper than buying a brand new plastic one and should last a good while longer too. With the PS pressure lines, you're probably better off taking it to a hydraulic shop and having them reseal it. Last I checked a brand new hose through the dealership was $545+GST and you'd be waiting on it a few weeks. Took my old one into Enzed and had it back the next day with brand new rubber installed onto the existing metal fittings. No issues nearly 2 years later.

Nice! Which EGR delete kit did you get? Haven't received mine yet but got a Bimmertune one on its way. Didn't manage to find any local or much cheaper that that. Which mechatronic seal kit did you get also? Have ordered a full Vaico kit but @Eagle apparently had some issues with his so am dreading it a bit.

Beauty! Welcome to the diesel E53 club. Love that color. Just working through my major servicing regimen on the new purchase. How fun was cleaning out the intake? Haven't thought about the transfer case actuator gears, might have to add it to my list.

The first parts order arrived so I dug into a major service. This batch was aimed at servicing the engine and was as follows: Glow plugs & module Crankcase breather valve Water pump, thermostat & coolant flush Oil & filters First thing to come off was the intake manifold. Really quite easy on these engines not having to disconnect any fuel lines unlike on the M54, just a bunch of nuts & bolts to undo. I was in for quite a shock once it was off though. I knew diesels were "dirty" engines but this I wasn't quite ready for. The intake runners were gunked up so badly that they must have been reduced to roughly half the original diameters. Cleaning these out became the biggest and most time consuming task of this whole endeavour. I went through 5 rolls of disposable rags cleaning out the intake. No matter how much gunk I scraped out, how many times I rinsed the intake through, more and more gunk just kept coming out. Insane stuff. Must have taken a good 4-5 hours just scrubbing away at the intake with rags, brushes and screwdrivers and rinsing it out with a garden hose to get it to a point where it was relatively sludge-free. I then stuck some rags down the openings on the engine side and picked away at the sludge with a screwdriver to get that cleaned up as best I could. To top it off I then made a simultaneously genius and moronic move in taping a piece of rubber pipe onto the end of a shop vac and sticking it down the openings - genius in that you could hear the sludge getting pulled out of the engine so got that end of things cleaned up really well; moronic in that the vacuum tubing now needed an almighty cleanup job itself. Win some, lose some. I then tackled the glow plugs. Have read that these are known so seize inside the engine and needed a really careful approach as to not strip any threads. I'm guessing it's more of an issue in colder climates as mine came out without any issues despite almost certainly still being originals. Glow plugs aren't really critical in our warm-ish climate but good to have the system functioning properly and get rid of some fault codes. The glow plug module is a bit of a mission to get to, sitting underneath a variety of coolant lines, wiring and vacuum hoses. To make access easier, you can remove a coolant flange bolting onto the block, which is what I did since I was draining the coolant anyway. The flange is known to break when working in that area so I ordered a spare Febi one just in case and bolted it on once the new module was in place, which ended up being a mistake as I later discovered. I felt the coolant hoses were a bit loose when reassembling but didn't think much of it at the time. Then with everything reassembled and the coolant topped up both hoses started pissing out fluid with the engine running, all over the brand new glow plug module. On the bright side, it took me just 15 minutes to remove the intake this time around so it didn't set me back too much. Luckily, the original flange didn't get damaged in the process so I just transferred over the gasket from the Febi one and bolted everything back up. No leaks this time around. I know Febi are hit and miss nowadays and have now ticked off my first bad experience with them. Water pump & thermostat went on without issues. The water pump was still original, the thermostat was date stamped 2021 and the coolant that came out was still blue and fairly clean so the car was at least somewhat taken care of. The radiator got a good rinse and clean and went back on as well. Still original but seemingly in decent nick, will have to keep an eye on it. Was surprised by how much of a mission it is changing out the air filter on these. The thing itself is massive and you have to take off the whole cabin filter panel, all beauty covers and several more covers just to get to it, and even then access is really tight with the cover panel hitting brake lines at the side of the engine bay that houses the brake booster. No wonder the filter that came out was filthy as all hell. Had claimed quite a few innocent lives throughout its tenure that thing. On the flipside, oil changes are a breeze as I didn't even need to drive it up onto ramps or jack the car up to have access to the sump. The PCV was a simple in & out affair. Also threw on new expansion tank and oil filler caps for good measure. The engine bay now looking clean & tidy. That's pretty much it on the engine side of things. Will do another oil change in a few thousand km's just to be safe as I don't have much in terms of service history. Have also put an order in for a proper EGR delete kit as I don't want to deal with the absolute horror show of cleaning a diesel intake manifold ever again. Have just unplugged and capped off the vacuum hose going to the EGR valve for now. Luckily it's the older, vacuum operated system on this thing and not the newer electronic valve so didn't trigger any engine lights and no coding required. The engine now breathes noticeably more freely and generally feels happier. Previously it would momentarily stutter at idle when first starting it up so am glad to have gotten rid of that. Have also poured a bottle of Techron fuel system cleaner into the tank to hopefully help her run a bit smoother still. I did discover a new issue that will need addressing sooner rather than later in the form of a split axle boot on the driver's side. Won't be a fun job by any means. Really hope the axle comes out of the hub without much hassle and isn't seized in. Another item I received in this batch was a new driver's side mirror glass. The old one had gone all brown and yucky, assumedly the auto-dim feature going bad. Seems like a rather gimmicky feature that I'm unlikely to miss so just ordered a "dumb" heated mirror as a replacement since it was 1/5 of the price - TYC brand at just 8 EUR a piece. The old one was a mission to get off and I ended up cracking it in my attempts to remove it, spilling that nasty fluid all over the place in the process. The new mirror is nice and clear and has a stronger convex so gives a better field of view than the old one, which is nice to have on a bigger car. I've since discovered the passenger side one to be held together with double sided tape and wobble at cruising speeds so have ordered a replacement for the other side as well. The next batch of parts is now on the way, including the CV boots, fuel and cabin filters that I forgot to include with the original order as well as transmission filter, mechatronic seals and other plugs & gaskets to start changing out the trans, diff & transfer case fluids. Won't be straying too far for the time being with the split boot but wifey's pretty chuffed with her new chariot.

Have been slowly chipping away at this thing over the past month or so. First order of business was a good deep clean inside and out. Discovered quite a few dings and scratches as you would expect but still presents quite well. The headlights are starting to get quite faded and unfortunately these are similar to E46 facelift coupes in that the lenses are molded into the headlight and aren't easily interchangeable for new ones. A mate of mine has the knack and gear for headlight restoration so get him to have a go as that cleans up the look quite drastically. The inside got a good deep clean and vacuum. The bigger mission was sorting out the various messes that someone had made of the wiring. There were some weird unconnected cables added on at the headunit end that I ended up removing and tidying up. In the trunk area, instead of a towing module I found whatever this contraption is. Haven't tested whether the trailer lights actually work yet but that also needed a few dodgy wiring joints tidied up. Hopefully it works as I'm having a hard enough time chasing down one towing module, let alone two. The car came fitted with a reverse camera that was refusing to work. I had a spare one sitting on a shelf so decided to investigate. Hooked up the new camera to the existing wiring - nothing. Hooked up the new wiring to the existing camera - nothing. Hooked up the new wiring to the new camera - works like a charm, so somehow, someone along the way had managed to mess up both the wiring and the camera itself. Upon closer inspection I was again greeted with a whole bunch of dodgy wiring - a combination of wires soldered, crimped, taped together, added plugs and even a terminal connection all covered in copious amounts of electrical tape, sticking out from behind trim pieces in the cabin along the length of it. Ended up ripping the whole thing out and running a whole new length from the headunit to the tailgate, using proper solder-heatshrink butt connectors and taking off door sills and trim pieces to tuck the cables tidily out of sight. The car came fitted with both front and rear parking sensors but neither were working so tried digging into that issue as well. I was fearing the sensors being faulty but the scan tool only gave a code for the gong so dug into that. Taking off the kick panel I discovered the gong wasn't plugged in at all and the plugs were nowhere to be seen. Took a bit of digging around to find the ends deliberately tucked away in behind the carpet. Someone really didn't want these to be found. Figured it would have been done because the whole system was faulty but to my surprise both front and rears work perfectly fine after plugging in the gong. So now the car has fully functional parking sensors and reverse camera. Steady progress.

Also, I keep seeing a slight damp patch at the bottom of the gearbox that feels a bit oily to the touch. It's never properly dripping so not an obvious massive leak but seems to be slowly weeping from somewhere. Almost looks like it's coming out from the bottom two casing bolts. The drain plug threads also seemingly look shiny at all times so could also be that. Then again those are the bottom most parts of the gearbox and it could just be accumulating down there from above. The plugs themselves were brand new so shouldn't really be leaking. Would it be a good idea to wrap some teflon tape around them next time I do a gearbox flush? At this point all the seals apart from the output shaft seal have been replaced. I do have one sitting on the shelf but they're not known to be particularly failure prone and I didn't feel confident enough to mess with pre-loading the output flange so left it alone for the time being. Not a big enough leak to start getting concerned about just yet but would be good to know if it's a common occurrence and whether there's an obvious remedy.

In a more sombre development, I stumbled upon whatever THIS is. Still struggling to figure out the rich running condition and with the beauty covers off messing around with the headers, I decided to swap out the spark plugs. The current ones were put in when rebuilding the engine and had only done around 12k km's since brand new but that did include the full break in period so, clutching at straws, I figured that might have gunked them up somehow. Easy enough item to tick off so might as well. Whilst at it, I decided to stick my cheapo Aliexpress endoscope dongle down into the cylinders and have a gander. Almost wish I didn't. Whilst 5 of the 6 cylinders/pistons looked pretty much spotless, cylinder 2 looked like it had a crater in the top of the piston. The camera resolution/quality of course didn't help and probably made it look like worse than it was. It was nearly midnight when I discovered it, which set my mind spiralling and I went to bed thinking the engine was toast. The next day I borrowed a better quality endoscope off a mate and had a second look which cleared it up a bit. What I originally thought was a hole was just some nasty carbon buildup but nevertheless the silver, shiny blob still looked like something burnt to the top of the piston. I ended up sticking a piece of wire down the spark plug tube and started picking away at it. Was pretty hard work getting any control and leverage on it but you can see chunks breaking off at around 50 seconds into the video. I taped the endoscope to the piece of wire and went at it some more. You can see a bunch of those chunks littered around, still no idea what it might have been or how whatever it is got there but hopefully not enough of it to do any real damage. I taped a rubber hose to the end of the shop vac, stuck that down the cylinder and tried to suck out the debris, then turned the engine over to get the exhaust valves open on that cylinder and blew it out with compressed air to hopefully clear out any remaining loose stuff. I also had a look at the exhaust valves themselves which didn't reveal any obvious defects. Full video investigation catalogue if anyone cares. The spark plugs themselves actually looked fine, not overly sooty and no obvious bits missing so no smoking gun there. Did a compression test just to be safe which showed around 170 psi but at that point the car had been sitting for close to a month so wouldn't have been an accurate result. Will recheck on a warm engine sometime. I reinstalled the old spark plugs for now. Once the headers got bolted up, I poured a bottle of Techron fuel system cleaner into the tank and topped it off with some BP 98 to hopefully clear out some gunk that might have accumulated and caused this. Need to go on a few more longer runs and give it some spanking to help burn off the remnants. Once that tank is up and the cleaner's worked its way through the system I'll do a proper compression test and install the fresh spark plugs. Bit of a nerve wracking episode that but the car is still seemingly running fine so seem to have gotten away with just a scare. Bit weird still that only one cylinder looked as bad whilst nothing of the like in any of the rest of them. Cars are pain.

Happy to vouch for a good product mate. Thanks for making these! I would've been left in a right pickle without it. Feel free to use the photos for reference or promo if that's something that would be of use to you.

I did also swap out the amber indicators for a fresh set of clears as some eagle-eyed folk might have noticed from those videos. TYC brand corners and fender indicators are good quality and still pretty cheap from Spareto so got sets of both ambers and clears last year. Paired them up with chrome bulbs from LEDPerf since they were the only ones I found (other than Aliexpress) that carried the smaller chrome fender indicator bulbs. Pricing seemed reasonable but did find dealing with them quite annoying so probably wouldn't bother again. Despite a .co.nz website and NZ flag plastered all over the place, they ship their stuff out from France which in my case took over 3 weeks to arrive with little to no tracking updates along the way. The bulbs look to be random brand and probably Chinese-made anyway so would just go direct to Aliexpress next time. Chrome bulbs do make quite a difference though and give a nice clean finish instead of the egg-yolk look you get with amber bulbs. With the fender indicators I somehow ended up with slightly different ones with one having a pearly white edge and the other more of a beige. Might tack on another pair with the next order to have a matching set since they cost the equivalent of a pack of chips. I've also taken up the practice of super-gluing in those metal tabs after having 3 of them shoot out one after another into the fender cavity when reinstalling them after a polish. Don't need the hassle of trying to fish those out again. Did enjoy the amber look but wanted to switch it up a bit after a a year and a bit on that setup and the car does look way more modern with the clears. Need to take her out for a scenic photoshoot up in the hills on a cloudy day sometime.

Have now put a few hundred km on with the headers installed and they've developed a nice bronze-ish tinge. Looks pretty cool. Performance wise, can't say I notice much of a difference. The engine does rev quite freely but then again I wasn't really complaining beforehand either. My butt dyno isn't awfully well calibrated and I wouldn't have realized it was 30hp below stock power numbers until we put it on the dyno. Gonna try address a few more things and do another power run at some point to compare. Having driven a bit monitoring fuel trims the LTFT's still keep jumping between 5.6 - 6.3 - 7.8 - 8.6 for both banks so doesn't looks like it's made a difference there. Would have been wishful thinking to expect it to have done though. Didn't notice a massive difference in sound either. It did make the tone somewhat deeper but the difference is very marginal and it still sounds quite subdued to my ear. At idle there is no difference at all, at around 4-5k RPM and above you do hear it more but not as much as I would have expected. I was hoping for a more throatier tone but with the rest of the exhaust remaining stock I guess the muffler does what mufflers do. I want to retain the secondary cats so as to not smell like a bag of rotten eggs so might look into getting an aftermarket muffler at some point instead, but that will be sometime in the distant future. Video #1 Video #2 Should have really made the comparison a bit more scientific and taken some 'before' videos and maybe a dB reading but of course only thought of it after the exhaust was already off the car. Here's a brief summary of my experience with the Malian Exhaust RHD headers: The flanges at the engine head end are perfectly straight, fitment is good and they bolt up nice and straight. The flanges on the exhaust side are horrible, it's like they never fitted them onto an actual car before rushing them into production - the angles are wrong, the lengths aren't even and the whole slotted bolt hole design is baffling - even if they did line up and weren't hitting each other when bolted up to the head, I have no idea what guarantees that the tubes remain in proper alignment. They had a previous version of these with stock-style flanges that apparently worked fine, why they moved away from it is beyond me. They've even kept photos of the original ones bolted up on an actual car on their website, yet sell a 'revised' kit that doesn't work. Again to reiterate - these will not bolt up to the stock exhaust without extensive modification. The position of the O2 sensor bungs is way off. Even cut down the Bank 2 O2 sensor is hitting the chassis, even with the heat shields bashed in. Could have clocked them differently since there's heaps of room to facilitate it but guess they never bothered test fitting. They could have omitted the secondary O2 bungs entirely since they're so tight against the chassis they're unusable anyway. I don't believe the stock steering linkage would have cleared even with brand new engine mounts so be prepared to fork out for a slim one. The supplied gaskets are garbage and went straight in the bin. As far as RHD alternatives go, there doesn't appear to be much choice out there. There's Gravity Performance, who don't ship to NZ, and there's Supersprint that are eye-wateringly expensive. There's also Coby ones that look to be mild steel and would still need some welding to mate up to the rest of the M54 exhaust. All in all, with the purchase price, paying for having these re-welded, the slim steering linkage and new gaskets, this exercise cost me around $1.2k, which is still pretty reasonable in my eyes, with @Eagle also taking a bit of a loss on the initial purchase. Despite not quite getting the sound gains I was hoping for, I feel it was still a worthwhile thing to do and a step in the right direction and I'd still do it again if I had to. Just would have been good to know what to expect before jumping into it so hopefully this might help someone else out there.

Cheers! I'm getting to it, just breaking the spiel up into parts as the posts are getting pretty long.

The next issue I ran into was the steering linkage. Having initially hooked up my stock one with the CMP coupler, there looked to be plenty of clearance... until I turned the wheel and the bolt holding the coupling to the main shaft started hitting on the headers. Video They claim that the clearance is there but might become a problem if your engine mounts are worn. Mine are barely 12k km's old and the bolt is not even close to clearing so I doubt it'd be any better with brand new engine mounts. Luckily, I anticipated this being a potential issue or that the clearance would be tight at the very least so I pre-emptively ordered a slim linkage from @modz. Great bit of kit, arrived quickly and well packaged with handy instructions, would definitely recommend. Glad I had it on hand by the time the headers came back from the shop so it didn't hold me up. Compared to the stock linkage the ends are clocked slightly differently so all I had to do was reposition the plastic alignment sleeve at the steering rack end. It does end up being slightly shorter than stock so the steering column does extend out of the firewall a bit further. Mine seems to have a lot of play in the column so might look to replace some bushes or the whole column at some stage. Heaps of clearance now so I'm happy as Larry.

With the catless headers being significantly more compact, bolting them on was a fair bit easier since they slid through easily enough so that the engine arm didn't need to come out again. I also replaced the stock studs with new ones from the N-series engines that are slightly shorter and have an E-torx head, making installation a lot easier than the double-nut method. I thought about reusing the manifold gaskets with the heat shields, mostly to retain the clips for the O2 sensor wiring but due to the different positioning of the bungs those wouldn't have worked anyway. The new headers are angled straight down, are quite a way away from the valve cover so keeping the heat shields probably wouldn't have had much effect apart from making access to the bolts a lot more tedious. Opted for brand new M52 gaskets that are pretty much identical to the M54 ones, minus the heat shields. The bank 2 O2 sensor (990mm) had enough length in it to fit into the factory clips, bank 1 however (570mm) was now considerably further away and wouldn't reach at all. The options were to order in a new longer bank 2 sensor (which might still have been too short) or make up an extension which I decided to have a go at. Not the first time the spare wiring loom has come in handy. Hacked it up a bit more, as well as a spare old O2 sensor and made up a nice factory-looking extension that blends right in. I only recently discovered these heat shrink + solder butt connectors and now swear by them. So easy to use and seem to create a nice, solid connection. 10/10 recommend. The additional new connection didn't fit under the beauty cover but slotted in between the valve cover and the fire wall and sits there quite securely. The other issue with these headers was that the bank 2 O2 sensor bung is positioned so that the top of the sensor pretty much sits right up against the fire wall heat shield. I bashed them in at that spot as much as I could but it's still mighty close. Not ideal but it is what it is. The exhaust was a bit tight going on but the flanges bolted up fine in the end. The bank 1 flange must still have ended up angled slightly wrong with a slight gap over top of it but luckily the edge of the inner opening looks to be slightly bulged and the gasket looks to be sealing fine.

Somewhat impulsively jumped into another side project in the form of RHD headers from Malian Exhaust / Kage Trading. tl;dr of it is - THESE ARE NOT A STRAIGHT BOLT ON. They will require (quite extensive) modification to bolt up to the rest of the exhaust, nor will they clear the steering linkage, contrary to their claims. Unless you have the welding equipment & experience, or are prepared to shell out another 1-1.5x the purchase price in paying someone to have these reshaped, my recommendation would be to AVOID. I knew some of the downsides prior to diving into it so had time to emotionally/financially prepare. These were originally purchased by @Eagle who discovered the fitment issues and subsequently abandoned them in favor of an M52 setup. I then took over the baton knowing that at the very least they'll need new flanges welded on in place of their stupid '2024 revision' slotted bolt hole design. Eagle also kindly provided the new flanges. I took off the stock manifolds (bit of a mission having to support the engine & taking out the exhaust side engine arm & mount to gain enough clearance to slide them out) and dropped both sets off at Flame Performance. They used the stock manifolds to make up a jig to accurately position and weld up the new flanges. Bank 1 was fairly straightforward and just needed a bit of extending and a bit of an angle adjustment. Bank 2 however was angled completely incorrectly and needed a lot of work. Also have them weld on the supplied bolts to turn them into studs and make installing the rest of the exhaust a bit less of a hassle. The initial test fit revealed that bank 1 needed to be extended by another 4mm so got dropped off back at the shop to get redone. With that done the angle between the two flanges was still slightly off but close enough for the gaskets to eat up the slack. I gave both headers a quick polish to get rid of the discoloration from welding and wiped them down to avoid having any fingerprints permanently burnt on. Came out looking pretty flash.

This topic pops up regularly on all sorts of forums and FB groups and I genuinely don't get why it's still a debate. BMW genuine blue coolant concentrate still works out to roughly the same price as any quality aftermarket equivalents, so why would you bother/gamble with anything else? I guess this green Penrite stuff is the closest equivalent that you'd get off the shelf from SCA - $57 / 5L = $11.40 / L I picked up 4 bottles of BMW concentrate from the dealership the other week, I believe I paid around $120 so is $30 / 1.5L of concentrate. Add to that 5L of demineralized water for $10. Typical fill would be around 6L so you're looking at 2 x $30 + $10 / 6L = $11.60 / L Supposedly, the genuine coolant is made to a specific formulation that works well with the alloy used in the engine block/head and the plastic/rubber parts comprising the cooling system. There's all sorts of debate as to whether that's true, whether other aftermarket coolants made to the required specification do the same thing etc etc. I could understand the inclination to take a chance on that stuff if genuine cost twice as much but there's literally next to no difference in price. If you care about your car, just go genuine. This is the one rare instance when it doesn't cost you anything extra.

Genuine question: wtf is a social media nepotist?

Good heads up! Looks to be a universal Black Friday deal. Never knew they even sold it. https://www.mitre10.co.nz/shop/castrol-edge-5w-30-engine-oil-5-litre/p/374696

Bloody Christ, what an utterly loathsome pack of individuals. Peak capitalism brain, hyper fixated on badges and the intricacies of coat hangers. How is this not a parody?

This fine specimen has popped up again, now through Sunday Drive. I do love me a touring probably more than the average person but this seems a bit bonkers for a 4-cylinder with close to half a mill on the clock. https://www.trademe.co.nz/5023124739

Check out Hyperdrive, seems to be plenty of options for that size. Alternatively, you could go 245/40R17 whilst retaining much of the tyre width. I wouldn't go 225 on a RWD car, not sure if they would work on a wider rim but hey, I'm not gonna tell you off either.

Oh great news! Price drop on the blue one in Chch, now available at a bargain $77k. Let's gooo

Don't get me wrong, I'm not a big fan of E60's and given a straight choice I'll take the E39 any day of the week, but at that price point... I know it's a silly comparison but the reason I mention an E60 (and not an F10 that are also available at around the $40k mark) is that there's a much wider choice of V8's out there, both older and modern, whilst an NA V10 is much more of a unique proposition and likely one of the last mass-market ones ever made. If I had to spend $60k on a super sedan I'd take the best E60 out there at $40k and have $20k left over in a maintenance fund, or hell... throw it at a manual conversion before I spend it all on a lazily presented E39.

Was wondering when a thread about this one would pop up... Pretty disgusting state of affairs when dealers are asking $20+k above market value without even wanting to spend a few hundred on a new shift knob or getting the steering wheel, leather seats properly treated. Close to zero effort and investment yet are asking a premium. Probably looked at that blue one listed at $90k and figured this one is a bargain at 60, not realizing the first one is horrifically overpriced by 2x. Pretty sure there have been much better examples listed for less very much recently. Not sure who would in their right mind would fork out $60k for it when there's a like 5 E60 M5's to choose from all at under $40k.

Old BMW's are a tough proposition unless you're doing all the work yourself. Even a cheap part like an oil pan gasket will cost 10x of the part itself to replace because of the sheer amount of labor involved. Generally, people that have deep enough pockets to pay to have their BMW's worked on move up to newer models anyway, so as the cars age they either end up with enthusiasts or at wreckers. Honestly, unless you plan on getting on the DIY bandwagon, you're probably best to move it on. Upshot is, the E87 platform belonged to one of the last BMW eras that were generally easy to work on and have heaps of documentation online for any type of job you could ever think to take on, so would be a great platform to start on. But yeah, if you're not that way inclined it's unlikely to make economic sense.