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SCM Thu May 19, 2011 1:20 pm

Hopefully I'm just getting ahead of myself but until my mechanic tells me otherwise I'm starting to research options for a new motor for my van. As much as Suby power intriques me, I live too far from any experienced installers to feel comfortable going that route.

I stumbled upon this thread where someone eluded to the possibility that building a WBXer any bigger than 2.2L should maybe be avoided.

http://www.thesamba.com/vw/forum/viewtopic.php?t=4...p;start=20

What are some reasons for that?

mariusstrom Thu May 19, 2011 1:34 pm

SCM wrote: Hopefully I'm just getting ahead of myself but until my mechanic tells me otherwise I'm starting to research options for a new motor for my van. As much as Suby power intriques me, I live too far from any experienced installers to feel comfortable going that route.

I stumbled upon this thread where someone eluded to the possibility that building a WBXer any bigger than 2.2L should maybe be avoided.

http://www.thesamba.com/vw/forum/viewtopic.php?t=4...p;start=20

What are some reasons for that?
I don't see anything in that thread indicating that >2.2L should be avoided, other than "it's more expensive".

SCM Thu May 19, 2011 1:47 pm

mariusstrom wrote: I don't see anything in that thread indicating that >2.2L should be avoided, other than "it's more expensive".

Insyncro said "I am not a fan of building the waterboxer past 2.2 myself.
Boston Bob was a good friend and he schooled me when I contacted him to build me a superboxer".

I also wonder if a performance-to-reliability issue is what has tencent sticking with 2.2L engines so far.

insyncro Thu May 19, 2011 1:52 pm

IMHO, 2.2 done properly is plenty.
Larger needs premium fuel.
If you have to have larger than 2.2, I would highly recommend buying directly from GoWesty.
You will get a warranty.
Does your mechanic truely understand all of the "needs and the does and dont's" of building a waterboxer larger than 2.2???
Can he handle it???

mariusstrom Thu May 19, 2011 1:53 pm

SCM wrote: mariusstrom wrote: I don't see anything in that thread indicating that >2.2L should be avoided, other than "it's more expensive".

Insyncro said "I am not a fan of building the waterboxer past 2.2 myself.
Boston Bob was a good friend and he schooled me when I contacted him to build me a superboxer".

I also wonder if a performance-to-reliability issue is what has tencent sticking with 2.2L engines so far.
Ahh, I missed that. My assumption (complete assumption) is that when you're making the cylinders bigger, you're necessarily decreasing the strength of the heads (since the "hole" in the head is bigger). Also may be cooling issues with the larger combustion that would happen.

Again, these are all guesses... I'm not an engine builder, YMMV, etc. :)

SCM Thu May 19, 2011 1:55 pm

insyncro wrote: Does your mechanic truely understand all of the "needs and the does and dont's" of building a waterboxer larger than 2.2???
Can he handle it???

My mechanic wouldn't be building, he'd just be installing.

If it turns out that I do in fact need a new motor (conjecture at this point, my mech hasn't even seen it yet) the wait for a tencent might be too much to bare in which case I'll be looking at something from GW.

insyncro Thu May 19, 2011 1:58 pm

SCM wrote: mariusstrom wrote: I don't see anything in that thread indicating that >2.2L should be avoided, other than "it's more expensive".

Insyncro said "I am not a fan of building the waterboxer past 2.2 myself.
Boston Bob was a good friend and he schooled me when I contacted him to build me a superboxer".

I also wonder if a performance-to-reliability issue is what has tencent sticking with 2.2L engines so far.

I am in the process of installing a Vanistan 2.2 motor with all the bells and whistles right now.
I stand by all I have said in the past.
I don't see any need for more than Chris offers...if you can get one.

With that said, yes the availablity is short and the waiting list is long.
If you want a superboxer, GoWesty is the answer I would consider.
The warranty is what you are paying for.

dylan

0to60in6min Thu May 19, 2011 1:59 pm

I don't have the answer.. reliability may be?

but looking around I notice that the upper limit off a cylinder is 600cc, which means that a 2.4 (2400cc) WBX can be built... bigger than that, more cylinder will be needed..

see.. BMW, Mercedes, Porsche.. with a few exception from monster trucks with 5.6 liter V8 (700cc per cylinder)

gl98115 Thu May 19, 2011 2:55 pm

I recently bought a camper with a 2.3 GoWesty motor. Runs pretty good on regular unleaded.

blakeck2 Thu May 19, 2011 3:04 pm

gl98115 wrote: I recently bought a camper with a 2.3 GoWesty motor. Runs pretty good on regular unleaded.

If I were you I would stop using regular and use the premium like suggested on the website :shock:

SCM Thu May 19, 2011 3:13 pm

blakeck2 wrote: gl98115 wrote: I recently bought a camper with a 2.3 GoWesty motor. Runs pretty good on regular unleaded.

If I were you I would stop using regular and use the premium like suggested on the website :shock:

They say that a 2.3 is alright to run on regular but they "recommend all Vanagons" use premium.

gl98115, what kind of mileage are you seeing and what kind of speeds can you maintain going up steep highway grades?

SCM Thu May 19, 2011 3:15 pm

deleted double post

BillM Thu May 19, 2011 3:23 pm

As said above I would really stop using regular in that 2.3. The few dollars saved is going to cost you later. I just sold a 91 with a Gowesty 2.3 and the po did nothing but use 91+. It had 50,000 miles and was still running excellent. Other than the usual preps I do to a "flip"'van all it needed was couple hoses engine wise. I am trying to talk another van that I maintain owner into ordering a 10cent engine. I'd love to install one. His throttle body set up really interests me. I want to see one first hand.

Bill
87 Westy
Zetec Turbo

gl98115 Thu May 19, 2011 3:47 pm

SCM wrote: gl98115, what kind of mileage are you seeing and what kind of speeds can you maintain going up steep highway grades?

Depends on the steepness of the grade, of course. The van was regeared in 3rd and 4th and with two folks and gear with two bikes on the back it was either 70+mph @ 3500+rpm in 4th or 60 mph @ 4500 rpm in 3rd (with a little pedal left). Going up new Priest Grade toward Yos was only limited by the slowpoke in front of me. Enthusiastic interstate driving (speed limit +5) yielded about 17.5 mpg.

As always, YMMV.

funagon Thu May 19, 2011 8:03 pm

SCM wrote:

I stumbled upon this thread where someone eluded to the possibility that building a WBXer any bigger than 2.2L should maybe be avoided.

http://www.thesamba.com/vw/forum/viewtopic.php?t=4...p;start=20

What are some reasons for that?

If you're a home builder, you can just replace the piston/cylinder combo for a nice upgrade to 2.2. Gowesty sells the piston kit to do this. If you want to go bigger you need to use a custom crank and custom rods, and possibly make some mods to the engine case. This higher compression engine will generate more heat and stress, so you'd better make sure your lubrication system and cooling system are up to snuff. In their larger engines gowesty adds oil jets to squirt the backside of the pistons, and maybe larger injectors. I would also add an external oil cooler to any WBX to control oil temps.

You need to worry about compression ratio (it should be increased over a stock WBX, but not too much!) and think about making the heads breathe a little better.

I agree with Dylan "insyncro." I have a 2.2 in my tin top passenger van. It's not a hot rod, but I've driven it fully loaded with gear across the U.S. and over the Rockies a few times. It does slow down on the high mountain passes, but it's reliable and gets me everywhere I want to go.

When I do a cost-benefit analysis, I think the most efficient/cheap way to go is to rebuild your 2.1 with 2.2 pistons, and upgrade to higher ratio rocker arms to help the heads breathe a little better (search the samba posts by tencentlife to read about upgrading to high ratio rockers). Adding an external oil cooler is a good idea for engine longevity.

Options for 2.2 pistons:

Gowesty sells a nice kit, 2.2 liter displacement, slightly higher compression. Goes on the same rods and put the heads back on. Nice increase in power.

Rocky Jennings has sold a custom set of rods and pistons to achieve 2.2 liters. I believe they are slightly higher compression than Gowesty's, which I would find desireable. (Or if I'm wrong about what Rocky offers, I think he has the experience to produce whatever you want, if you know what you want, that is.)

Chris (tencentlife on the samba) has machined custom pistons for the custom engines he sells, also higher compression than Gowesty's 2.2's. He's probably busy building engines; he may not want to produce pistons for an unknown engine that's not his own.

I have often thought about increasing the compression ratio, for more power, by taking the heads off my Gowesty 2.2's, removing the copper compression ring, and lapping the cylinders into the head (to reassemble without the compression ring). But then in order to make the water jacket seal properly I would then have to machine the head surface to remove material equal to the thickness of the missing compression ring (plus lapping depth?). Or, I could use a custom, thinner water jacket seal.

Sounds like a lot of work when, the truth is, my 2.2 WBX has been trouble free for many years and tens of thousands of miles of road tripping. I find it hard to justify pulling it out of the van just to squeeze a little more power out of it. More likely I'll tinker with a spare WBX so I can swap engines one day.

tencentlife Thu May 19, 2011 8:34 pm

The short answer to the OP's question is that there is no reason at all not to build a wbx engine larger than 2.2, but one ultimately encounters limitations imposed by geometry, mainly, and of course costs and the very limited range of available alternative parts. The parts limitation can be overcome with loads of money, but then in order to make that work one has to sell a lot of engines to recoup the R&D and the cash commitments to minimum production runs (thousands of dollars for even small runs of relatively cheap parts).

The various geometric factors get a little complex for laypeople to grasp so I'm not going to go into detail except to say that the dimension that most limits the growth of this particular platform is width, in that the water jackets and their fixed relationship to the cylinder heads limit how wide you can make the longblock without making expensive crankcase fabrications to alter that, modifications that would never be practical to do on even a limited production basis, and to my knowledge no one has ever done (except Oettinger whose answer was to add 2 more cylinders, with VWAG's sanction and backing; even so, that project must have been a massive suckhole for deutschmarks).

But a couple things that were said here jump out at me that I should probably swat down: one, the notion that 600cc is the maximum size for a cylinder? Where does that come from? That may have some truth insofar as what is convenient or economical but there are no principals of physics I am aware of that would dictate such a limit. There are engines in use where a man can walk in a circle inside one cylinder; its swept volume is larger than that of a VWvan (not the van's engine, the van!). I know my example is extreme but I think it illustrates the point.

The other was Dylan's remark that a larger engine would require premium fuel. What I suppose you meant was a larger GW engine does, but generally speaking the fuel requirement is completely under the control of the engine designer.

I myself have plans to produce a 2.4 wbx when I can invest the time to develop it, my plans are pretty well worked out and use existing parts and methods that will be practical and economical to implement in real life on my small production basis. My personal feeling about GW's range of sizes is that they are doing a great thing up to their 2.4, but the way they build their 2.5 is putting the parts they use at stress levels that I would not venture to do myself. I think that that is the size where it would have been better to do some crankcase and cylinder head modifications rather than making the cylinder walls thinner and thinner while those same cylinders are each producing more power; there are two lines on that graph (power vs. strength) and they are diverging, that's not the direction I would choose to go.

msewalson Thu May 19, 2011 8:58 pm

If I were you I would get an order into 10cent ASAP.

I've been in a vicious cycle on what engine to put in my syncro when the old wbx finally craps out. First it was a Zetec then the Suby 2.5 but I have finally come to a decision after seeing a 10cent motor at Syncro Solstice. Sure it's a long wait but totally worth it in the long run. Plus, I would rather buy an engine from a builder that is booked a few months out from one add on the Samba vs. a builder that has a web site and a fairly quick turn around. But that's just my opinion so take it for what it's worth.

Matt

Zeitgeist 13 Fri May 20, 2011 7:23 am

WBX porn thread. The counterweighted crank gives me the shivers

insyncro Fri May 20, 2011 7:41 am

I didn't know Chris had a 2.4 in the works.
I would surely back that product when ready.
I will rephrase my earlier statement with:

I feel a 2.2 is best for most Vanagon owners, going larger will cost more to build and maintain plus premium fuel should be used.

I would not consider a 2.5 any longer.

Once my current Vanistan 2.2 is running I will certainly post my impressions of the power and driveability over a stock 2.1.
Other add on work has been added to the build so it will be about a week before the motor is reinstalled.

dylan

silversync Fri May 20, 2011 9:34 am

tencentlife wrote: one, the notion that 600cc is the maximum size for a cylinder? Where does that come from?

Yes, the Porsche 944 S2 and the 968 have 3.0L inline 4 cylinder engines, or 750cc per cylinder. But they use balance shafts to counter the vibrations from such large cylinders, and they rob about 5 hp. These are very smooth and reliable engines. I wonder what kind of vibrations would exist in a boxer configuration.

Roland



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