Last post on Nov 24, 2012 at 8:27 AM
You are in the Subaru B9 Tribeca
What is this discussion about?
Subaru B9 Tribeca, SUV
#2025 of 8368 Re: is anyone else getting bored with the boring and is that off topic? [nj
Mar 02, 2005 (8:28 pm)
I disagree about the "boring" aspect of this recent discussion. varmint's post at varmint, "Subaru B9 Tribeca (B9X)" #2009, 1 Mar 2005 10:26 pm indicates he understands the issues:
Technically, Subaru could increase the bore. I'm not saying they should, but they could. If anyone else actually read the article cited there, they'd find that Honda engineers had to overcome numerous obstacales/difficulties to get that extra 3-mm (0.11-in) bore. If FHI were to able achieve the same success and reduce the "web distance" on the B9's engine to only 6-mm from 9.2-mm, the EZ30 could become the EZ32 - still not close to a 3.6L engine. But why did Honda's engineers spend so much effort and yen? The article explains clearly why Honda's engineers were jumping through all of those hoops:
Using a technique similar to Honda's quad sequential-sleeve design, they might get the the distance between bores below 9mm. Honda got it down to 6mm.
With this liner construction, the web distance, or distance between the inner walls of the adjoining cylinders, could be reduced to 6 mm from the separate lines' 9 mm, while retaining the same bore pitch. This was the essential requirement so that the new block could be cast and machined on the existing Suzuka lines.It's VERY expensive to start up a new engine production line, which apparently is necessary to make engines with a new bore pitch.
An article at http://www.sae.org/automag/globalview_09-00/06.htm describing the development of FHI's EZ30 engine makes the issue of changing bore pitch even clearer. According to Noriaki Sekine, Manager of power unit development at FHI:
"Getting a new bore pitch-the distance between two adjoining cylinder centers-is really a once-in-your-engineering-life occurrence," said Sekine, "so significant is its influence."
With this in mind, I'd say that the recent engine displacement discussion here has veered not to boring, but to, how shall I say this politely, uninformed. Consider this contribution from ateixeira, "Subaru B9 Tribeca (B9X)" #2014, 2 Mar 2005 1:46 pm piece by piece
They could stroke it - remember the Tribeca's platform is wider, so it could accomodate a 3.3-3.6l or so engine based on the EZ30.Stroking an engine doesn't change its external dimmensions.
Or we could see some form of the EJ257 turbo, maybe with 280-300hp if Subaru wanted to keep it affordable.A four-cylinder spark ignition engine is a non-starter with the B9 Tribeca.
An STi could get the H6 and a turbo, but that would put prices in the $40s, and then everyone would be screaming about the price.A B9 Tribeca wouldn't need to called an "STi" to be equipped with a turbo EZ30 and the only ones who'd whine about the price would be those who paid $50K for some other wimpier brand.
I bet there are several design studies going on simulateously. The ST-X had a supercharged engine that never made it to production. So just because a certain engine is rumored, even factual, does not mean it will make production.The ST-X design and fabrication was stricly an SOA effort. SOA hired a Michigan company, SVI (see http://www.subaru.net/owners/prototype/stx/stx.htm and http://www.automotive-technology.com/projects/subaru_STX/subaru_STX4.html) to build the ST-X and its powertrain. To say there are "several design studies going on" is hardly profound. FHI's CEO has declared they're working on both hybrid and diesel engine development. But this in no way supports the idea that FHI is working on a 3.6L engine for the Tribeca.
Mar 02, 2005 (8:41 pm)
Joe over at www.cars101.com posted some new info on the following page, including options and interior/exterior color combinations for each configuration that will be available. It's VERY nice to see Subaru offering a choice of interiors for most of the exterior colors. (Thank You, Subaru!)
Disappointing to see so many little "premium" touches (like puddle lights & the auto-dimming mirror) are options, but I'm sure Subaru's trying to keep that MSRP down. Also somewhat disappointed the audio upgrade is only available with a bump up to leather. The upgraded audio should be STANDARD across the line, since this dash won't allow for aftermarket upgrades.
#2027 of 8368 Re: crumbs [jeffmc]
Mar 02, 2005 (9:10 pm)
Thanks for the heads-up, jeffmc. I can see another contingeny that'll be disappointed (as in: This Sucks) - those who wanted a larger Outback (i.e. 5-seater) with all the ammenities. Their only factory options are cloth/leather and color. They're denied the NAV, Rear Seat Entertainment (RSE) aka DVD, and upgraded sound system:
STD: 100-Watt AM/FM stereo with MP3-compatible single-disc in-dash CD player, 6 audio speakers
UPGD: 160-Watt AM/FM stereo with MP3-compatible 6-disc in dash CD player, 9 audio speakers
The only options the 5-seater folks can order are the port (or dealer) installed options.
#2028 of 8368 Re: crumbs [jeffmc]
Mar 03, 2005 (7:52 am)
Hmmm... Anyone else having trouble accessing the cars101 site today? Usually I don't have a problem with that site...
#2029 of 8368 Re: crumbs [rsholland]
Mar 03, 2005 (7:55 am)
I can't access cars101.com, either.
Mar 03, 2005 (8:02 am)
The 1.8l was a boxer (EJ18 is related to today's 2.5l).
It was the Justy's tiny engine that was an in-line.
But the Leone, GL, BRAT, SVX, Loyale, XT, Impreza, Legacy, Forester, and Outback have had boxers.
jon: if they can get to 3.2l by boring it out like Honda did, they could also stroke the engine to obtain even more displacement, no?
I just feel like you conclude that certain things are not possible, but they only seem impossible, as Honda's example with clever cylinder liners proves.
Stroking an engine doesn't change its external dimmensions
You sure about that? I would expect that the boxer would end up wider.
Mar 03, 2005 (10:45 am)
Thanks Jon. I've learned something new today. Those links are great material. It's not easy to find details like that.
"...if they can get to 3.2l by boring it out like Honda did, they could also stroke the engine to obtain even more displacement, no?" - Juice
Not sure, Juice. When modifying an engine by stroking it, the crank offset (not sure of the technical term) must also be enlarged. Otherwise, the piston cannot take advantage of the longer stroke.
Subaru designed the engine with very tight bore spacing making for a very compact fore/aft design. 9.2mm doesn't leave much room for expansion. But with boxer engines, and the Outback's relatively narrow stance, I would assume width is of equal importance. I'm making a big assumption here, but if Subaru were going to build the engine with such a tight web, I'd expect they didn't leave extra space in the bottom... excuse me.... "middle".
No, I see two realistic possibilities. The first is that Subaru didn't expect the hp war launched by Nissan. So they built their H6 with the assumption that it was big enough to carry them for quite a long time. The second is that they decided from the start that this engine would get upgraded via forced induction.
Personally, I think the second is the more likely of the two.
Mar 03, 2005 (10:53 am)
I'd actually prefer to see a light pressure H6 turbo, but some people are very averse to them, perhaps scared from the typical problems encountered with them in the 80s.
#2033 of 8368 Re: H6 turbo [ateixeira]
Mar 03, 2005 (11:04 am)
True, but look at Volvo's XC90. Until the new V8 showed up you had to choose between a 5 or 6 cylinder turbo. I think both have sold fairly well despite having the turbo.
Mar 03, 2005 (11:46 am)
turbo-diesel. (farmer in me creeping out).