Date: Thu, 13 Oct 2011 06:20:33 -0700
Reply-To: Don Hanson <dhanson928@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Don Hanson <dhanson928@GMAIL.COM>
Subject: Re: Tires- 16" recommendations?
In-Reply-To: <011f01cc896c$1716df70$6401a8c0@PROSPERITY>
Content-Type: text/plain; charset=ISO-8859-1
On Wed, Oct 12, 2011 at 10:50 PM, Scott Daniel - Turbovans <
scottdaniel@turbovans.com> wrote:
> you'd be in 3rd gear up to 70mph
> if the tires are much taller than stock.
> scott
>
> Does the transmission 'care' if you are in 3rd or 4th? Did they build
them with a weaker 3rd gear set, engineering them with the assumption that
every Vanagon would always be shifted into top gear, and the other gears
would be used only to reach that final gear or to climb steep hills?
I bet Daryll knows, since it is his trade, and he drives a turbo Ford
vanagon syncro, if I am not mistaken.
Sometime I'm planning on getting 15" steelies for my Worker/ Traveler Van,
for better ground clearance and for a wider tire selection. Increasing my
wheels' diameter will lower the engine rpms at a given speed. My 2.0L ABA
inline Jetta motor is most happy at ~3500<>4500 rpms. When I do change to
larger diameter tires, I will probably be spending more time in my 4th gear
(5sp manual tranny) than I do now. I don't think the tranny should care,
but I only have about 60k miles of my own on this combo, so I don't know for
sure, from re-building one... yet.
I often run in 4th gear when roads cause me to travel below about
60mph.....Through the mountains, on long unpaved back roads, etc. When I do
change to 15" wheels and tires, I will be running in 4th even more... I hate
'lugging' a motor that is designed to be revved. I think it is really
really bad, asking a motor to contain an exploding full throttle fuel
mixture charge, and to *try* to move the big ole vehicle a long distance
with each piston stroke..... Dang, it pains me to do that...
.I wouldn't think the VW engineers, who designed the gears for the diesel
Van tranny like mine, ever in their wildest dreams expected the vehicle to
be in 5th gear for very long...only down hill or with a tailwind...(grin)
Did they actually make the final drive gears in their transmissions more
'stout' than the rest of the cogs? I don't think they would have (but you
never know about the Gang who designed German vehicles) only beefed up the
final drive gears in all Vanagon trannys and make the other ones weaker...
The WBX , I am told, is a more laid-back motor and likes to run around 3k
rpms. I *hate* making my motor work at rpms like that.......It sounds so
much happier at 4500, so smooth and responsive...even at 5 grand I have to
remind myself to shift soon. So when I put larger wheels on, I may be
using my 5th gear more like an Overdrive....somewhat.
I guess the one drawback to raising my gearing by increasing wheel
diameter is that all my will be taller, too...I may even have to use 1st
gear now during normal driving, for starting up from stopped, and I may
lose some of my ability to 'crawl' through streambeds or negotiate rocky
rough terrain without slipping the clutch.
So, if you put huge tires on a van and drove it in 3rd a lot (or in my
case, 4th) would that lower gear give up sooner? Is it weaker? I do
already realize the designers optimized the driveline for the vehicle and
any change is going to have some negative ramifications, so please hold the
"Never ever change anything they did at the Factory" replies, eh? (grin)
Don Hanson
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