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 Post subject: Tire Size
PostPosted: Tue Apr 10, 2012 8:15 pm 
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Joined: Sun Nov 11, 2007 4:11 pm
Posts: 79
Location: Seattle, WA area
What are the biggest size tires I can put on my long bed 1981 PUP without modification?

I was also wondering about suspension modifications that would allow me to load the little guy without the bed collapsing to the ground. I know it's not a one ton, but if I throw a 2*4 back there it starts to sag. Any suggestions?

thanks

Brett

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Brett (1981 isuzu pup longbed diesel, about as bare bones as it gets)


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 Post subject: Re: Tire Size
PostPosted: Tue Apr 10, 2012 9:41 pm 
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Joined: Fri Dec 14, 2007 11:25 pm
Posts: 1230
Location: Puyallup, WA
You have 58hp with power nothing. Even 195/75/r14 is a stretch. In the NW 185/75/14 will keep your r's up climbing hills but freeway speeds will suffer especially if you're runnin a 4speed.

J.C. Whitney sells overloads for these rigs, used to be about 40 smackers. Jerry


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 Post subject: Re: Tire Size
PostPosted: Wed Apr 11, 2012 2:23 pm 
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Joined: Fri May 16, 2008 6:24 pm
Posts: 2684
Location: oregon
its your ride and you can run the biggest tire you can fit on it should you wish to, but i think most people on hear would not advise that.


the odd ball in the 2wds is with a auto trans, they turn 200ish higher rpms then a 4wd, and don't have the space for a big tire like a 4wd does.
any thing under 3,200 at 60 with the auto trans is good. a 185/75/14 tire with a auto trans will put it at about 3,400-3,500 rpms :shock: :shock:


for most 2wds, about 2,600/2,700rpms at 60 is a good number to am for..
for a standard model that's a 185/75/14 tire at 2,600 rpms
for a mpg+ model that's a 195/75/14 tire at 2,700 rpms even though the rpms are higher, being that there's no O\D mpg is the same or better then a standard model.

for more power from a stand still up to speed or on hills, down size those one or two sizes. granted mpg at road speed will suffer a bit by doing so.

a 4wd model with a 4speed 30/9.50/15 tires are needed to get rpms down to about 2,750 at 60mph, there axles are geared the same as an auto trans, but you don't have the slip factor of the auto trans converter that does not lock up.


http://www.rocky-road.com/calculator.html

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rust free frame 1981 4wd luv for sale no engine\trans Cliky to see

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 Post subject: Re: Tire Size
PostPosted: Thu Apr 12, 2012 11:56 pm 
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Joined: Thu Apr 01, 2010 7:56 pm
Posts: 401
Location: Vancouver, WA
I'm running 205R70-14 on a set of 6" rims. The 205R70-14 is very close to the overall stock tire height. My rims have about a 2" negative offset from the stock wheels so they stick out a small amount from the fender. I use front mud flaps.

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-gary

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1982 Chevy Luv 2wd short bed diesel w/ veggie conversion (under construction)
1999 Isuzu Trooper 3.5L Gas


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 Post subject: Re: Tire Size
PostPosted: Fri Apr 13, 2012 1:11 am 
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Joined: Sun Jan 03, 2010 2:32 pm
Posts: 1734
Location: camas WASHINGTON
ipupgarys tires are made out of chocolate, dark chocolate :lol:

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1986 turbo/d 4x4 SB
2-1981 2wd diesel LB
1981 4wd diesel SB
1982 diesel 4x4 SB
1985 S-10 diesel extra cab 1981 2wd diesel SB /and several parts trucks


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 Post subject: Re: Tire Size
PostPosted: Fri Apr 13, 2012 12:14 pm 
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Joined: Thu Apr 01, 2010 7:56 pm
Posts: 401
Location: Vancouver, WA
I found this on the LUVtruck.com web site:
=========================================================
Link: http://www.1010tires.com/TireSizeCalculator.asp

Site Name: Tire Size Calculator
Posted By: Randall Flagg
Description: Ever wonder what those oversize tires were doing to your speedometer? Here is a site that tells you how off your speedo is with different than stock tires on your LUV. Its easy to use, just enter the stock tire size (185 75 R14), then enter your tire size and compare the two. This site gives alot of info, like how many revolutions per mile each tire is traveling, and also how much off the new tires are compared with the old ones.

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-Gary

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1982 Chevy Luv 2wd short bed diesel w/ veggie conversion (under construction)
1999 Isuzu Trooper 3.5L Gas


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 Post subject: Re: Tire Size
PostPosted: Thu Apr 19, 2012 5:37 am 
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Joined: Mon Feb 27, 2012 11:00 pm
Posts: 56
Location: Thailand
Hi, Gary
Your pick up is very nice and classic.


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 Post subject: Re: Tire Size
PostPosted: Thu Apr 19, 2012 12:05 pm 
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Joined: Thu Apr 01, 2010 7:56 pm
Posts: 401
Location: Vancouver, WA
Thanks. I love my 205R70-14 tires on my Pup. With the gas shocks and the new front end compoments from J. Lemond, this baby handles like a sports car. I'm loving it!

-Gary

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1982 Chevy Luv 2wd short bed diesel w/ veggie conversion (under construction)
1999 Isuzu Trooper 3.5L Gas


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