For gearing purposes I use rev/mile.

185R14  about 815 rev/mile
215/65R16  about 770 rev/mile

That is about a 6% difference. About 1.5" different diameter.

Yes you can feel it. Sometimes it helps, sometimes it hurts, not by much.

I have that size on 2 of my Vanagons. I like 215/65/16 because it
commonly comes in Load 98 and is readily available in XL Load 102. I use
the XL at 102. Both vans have stock 2.1 engines, manual trans.

Mark

Stephen Grisanti wrote:
> Okay, here's a tire diameter-specific question for you folks using 215/65R-16 tires: Do you feel like this tire size's height increase over stock has adversely affected your van's effective gearing?  My '87 with the stock 2.1L engine currently has the stock tire size, 185R-14C with an overall diameter of about 25 inches.  I have a set of 16" CLK wheels in the garage and will need tires before the next trip.
> My Mopar minivan uses the 215/65R-16 and that tire measures about 26" in diameter.  Is that one inch increase too great an increase over the stock size for the van's stock engine to pull comfortably, or should I consider a shorter tire with a diameter closer to stock, like a 205/65R-16.  I'd prefer the 65 series to a 60 for a little more sidewall height for a given width, and I've read that a one-inch increase in tire height is about the max recommended for a stock driveline.  I'm not anticipating a Sube swap or trans rebuild and regearing at the moment, so nothing else should be changing anytime soon.  The current engine is healthy but it is a WBX so not a powerhouse.  Thanks!
> Stephen
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