Mark,
You did great job researching conversions and gave unbiased information.
Exellent!I can only add that at 3800 rpm pushing gas pedal in Suby-powered Vanagon with AT
feels like it is going to fly...
Leon
85 Subwagen Westy

Mark Keller wrote:

> Thanks to the many responses regarding my question of actual torque and
> horsepower of the various alternative power plants vs the waterboxer. I
> skipped the TDI because I think it is difficult comparison to fit here.
> The engine is very well suited to Syncros according to response to me
> and  I'd agree.
>
> I searched several sites looking for good data. Most came from:
> VolksMotorsports, Dave Marshall, http://www.cobbtuning.com/tech/sohc/,
> and Vanagon.com for which I was able to get some useful data regarding
> power output in the 3800 RPM range for these engines.  I used a fixed
> 3800 RPM since the automatic van cruises at 65 mph an 3800 RPM.
> Therefore this post purports to indicate what amount of power is
> actually available when driving at speed.
>
> The basic numbers indicate the horsepower at the crank and wheel for
> 3800 RPM. I read a good article on Dyno results which essentially says
> that +- 5 hp is a pretty tight tolerance, so these numbers can be
> argued, but I'm looking at general picture of what to expect.
>
> Engine  @3800 Rpm                       Crank Torque & hp       Wheel Torque & hp
> Stock                                   112 ft lb.      82 hp           80 ft lb. 58 hp
> Rockers and Chipped             128 ft lb.      94 hp           90 ft lb. 66 hp
> Lilly's (low guess)             143 ft lb.      104             100 ft lb.      72.8 hp
> Marshall I -4                   113 ft lb.      82 hp           80 ft lb.       58 hp
> Subaru 2.2                              137 ft lb. 100 hp       95.9 ft lb. 70 hp
> Subaru 2.5                              166 ft lb. 120 hp       116 ft. lb. 84 hp
> Subaru flat 6                   2,000 ft. lb.  1447 hp          1400 ft lb. 1012 hp
>
> Notes: I used 30% loss per Volks motorsports dyno's.  I estimated
> Lilly's to be 10 hp more, just on the fact that the chip and rocker dyno
> on motorsports doesn't have the headwork or cam, or all the other
> modifications .  Lilly is probably more but he is at least this in my
> opinion.        The Subaru is my guess base on torque at 163 ft lb. @ 4400 rpm.
> Certainly Ballpark. The six is fantasy.
>
> My thoughts. Well the most surprising thing I came across was the weight
> of the Subaru is 262 lb.  compared to the 400 lb. of the waterboxer,
> which is light. I know the real world difference are probably less than
> 140 lb., but I actually expected the Subaru engine to weigh more.
>
> Well the waterboxer certainly isn't dead yet.  By Putting the Pawter
> Rockers on, and setting the timing very carefully and adding a K & N,
> you would probably put any waterboxer back into the game  for less money
> than any other option. The waterboxer dollars start to add for anything
> greater, and it's a tough call if a total rebuild in order since so many
> intangibles come into play. I'll stab at some intangibles
>
> The waterboxer is a tough reliable engine.  Psychologically many are
> justifiably weary of it. The problems are really solved, but to bring
> your engine into conformance may be to much too bear.  Certainly the
> power numbers indicate that a corrected waterboxer is good engine among
> the other choices.
>
> The inline 4 seem like a good choice for a basic vanagon. It's more
> advanced with knock control, I don't known about the weight, with an
> iron block, my guess is that it's about the same or marginally the
> heaviest among the choices .  The power is the same as an un-modified
> waterboxer.  Personally I'd avoid this engine in a westy if converting.
> Why pay the price and not get any more performance.  And extra weight,
> would actually mean less performance. The Subaru seems best for a West,
> less hoses and such, less weight, and at least the same power as a
> corrected waterboxer.
>
> The Subaru is an engine that has many strengths and technology on it's
> side. My feeling is that it can produce a constant 100 hp.  The light
> aircraft conversions use the engine at 100 hp constant duty.  Looking at
> Google search on the engine reveals that the after market is actively
> using and modifying this engine in many high performance and
> turbocharged areas. If making a war wagon is your speed this is the
> motor. These folks are convinced the motor is bulletproof and worthy of
> investing their milk money.
>
> Other bit and pieces.  I read that the big bore 2.5l has some
> compromises to fit into the original chassis, mainly a short stroke, and
> questions about reducing headgasket sealing area. The article I read was
> on 10 psi Turbo charging it, and they were ok with the issues for what
> it's worth. The six is a low production run motor, less than 50,000 in
> the years it's been produced.
>
> Thanks for listening.
>
> Sincerely,
>
> Mark Keller
> 91 Carat
> Cowichan Bay, BC