If your only concern is accelleration, then yes, you should go with a super light weight wheel, with little itty-bitty thin tires, with none of that heavy reinforced sidewall junk either.  Take the valve caps off, too.
However, last i heard, vanagons weren't really competing with, well, ANY other vehicle in a drag race (except maybe an air-cooled bus :-).  Where the v-dubs really shine is their handling, and the larger wheels/lower pro tires accentuate this.
Did my van work before i installed those apparently portly Carat2 wheels?  Yeah.  Does it feel like it drives better after the install?  Yeah.  I can't definitively say if it is either the wheels or the new tires, but the combo works better than stock.
To answer your "seat of the pants" ride quality impression Q, though, my synopsis is that little bumps are a teeeeny bit harsher.  Due to heavier wheels or shorter sidewall?  I dunno, but it doesn't really bother me.  If i was concerned about a hugely plush ride, i'd just get an Impala or somethin.  Accelleration is still, well, like a vanagon.
Now i just need the bigger brakes to fill up that extra wheel space (the real reason i went 15 in the first place).
-Damon

 James wrote:
I've been considering doing the 15" wheel/tire upgrade and noticed that some
of the replacement SA alloys weigh quite a bit more than the stock 14" alloy
(18lbs) (according to GoWesty's specs).

Which gets me thinking about the effect that weight has on performance. I
would think the added unsprung weight (again, 28%) must have a very
significant effect on handling and suspension response. And I've "heard"
that 1lb unsprung = 10lbs sprung. So, 5lbs more per wheel = 20lbs more
total unprung = 200lbs sprung. More rough calculation...that would yield
about a 1 second slower 0-60 because of rotational weight.

I hope I'm missing something here. What are people's real
world/seat-of-pants results after going big? It almost seems like the
benefit of the larger/wider tire (in our favorite brand) would be outweighed
by, well, weight.

Curious.

James
90 Carat

'84 Westy

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