From owner-fsj-digest-at-digest.net Thu Jun 23 03:00:57 2011 From: fsj-digest fsj-digest Thursday, June 23 2011 Volume 01 : Number 3733 Forum for Discussion of Full Sized SJ Series Jeeps Brian Colucci Digest Coordinator Contents: RE: xj: RE: fsj: Re: original tire size - 1963, conversion table??? fsj: more tire tech info [none] FSJ Digest Home Page: http://www.digest.net/jeeps/fsj/ Send submissions to fsj-digest-at-digest.net Send administrative requests to fsj-digest-request-at-digest.net To unsubscribe, include the word unsubscribe by itself in the body of the message, unless you are sending the request from a different address than the one that appears on the list. Include the word help in a message to fsj-digest-request to get a list of other majordomo commands. ---------------------------------------------------------------------- Date: Tue, 21 Jun 2011 12:38:28 -0700 From: Jim Blair Subject: RE: xj: RE: fsj: Re: original tire size - 1963, conversion table??? Probably powerlok > Date: Tue, 21 Jun 2011 08:32:07 -0700 > From: john-at-wagoneers.com > To: xj-at-digest.net > CC: fullsizejeeps-at-gmail.com; erniesilva-at-gmail.com; fsj-at-digest.net > Subject: Re: xj: RE: fsj: Re: original tire size - 1963, conversion table??? > > not always easy to find... or see... :) > > yep...limited slip, posi and lockers make it a bit more challenging... but > are nice to have, well not so much lockers... > > my '67 Wagoneer had a nice limited slip rear end... likely an auburn posi, hard > to say, likely factory... what was it back then? > > john > > > > ----- > ------------------------------------------------------------------------ > -o|||||o- > Snohomish, Washington - where Jeeps don't rust, they mold > http://AMSOIL.com/redirect.cgi?zo=283461 > http://JohnMeister.com HTTP://WAGONEERS.COM http://fotomeister.us > ------------------------------------------------------------------------ > > > On Tue, 21 Jun 2011, Jim Blair wrote: > > # All the Dana axles have the tag (front and back) from the factory. Model 20 > # rear used '80 to '87ish had a letter code stamped in the center housing next > # to the passenger's side axle tube. The ring and pinion have the tooth set (ie > # 49-18) stamped on the edge of the gears. Lifting one tire won't work if it's > # posi. 8^P > # > # Jim Blair, Lynnwood, WA '87 Comanche, '83 Jeep J10, '84 Jeep J10 > # > # > # > Subject: fsj: Re: original tire size - 1963, conversion table??? > # > To: erniesilva-at-gmail.com; john-at-wagoneers.com > # > CC: xj-at-digest.net; fsj-at-digest.net > # > From: fullsizejeeps-at-gmail.com > # > Date: Tue, 21 Jun 2011 14:51:37 +0000 > # > > # > If there is a data plate or stamping it will usually be on the left side of > # the cover. It could be in the form of the ratio, or list the ring and pinion. > # > > # > On my 81 it had the ring and pinion think it was 49 and 18. That works out > # to 2.7222. > # > > # > The other way of determining the ratio is to jack up one tire, transmission > # or xfr case in neutral, and rotate the tire one revolution, counting the times > # the driveshaft will spin. > # > If you have a limited slip this might not work. > # > > # > Or by taking the cover off, change the gear lube while you're at it, and > # count the teeth on the ring gear and pinion. > # > > # > Or you could take a known tire diameter, transmission in a 1:1 gear, drive > # at 60 mph with a gps, and measure the engine rpm and use the formula on my > # server, or some variation of this. > # > > # > > # > *** john at http://wagoneers.com *** > # > > # > -----Original Message----- > # > From: Ernesto Silva > # > Date: Tue, 21 Jun 2011 09:35:09 > # > To: john > # > Cc: xj-list; full size jeep list > # > Subject: Re: original tire size - 1963, conversion table??? > # > > # > Well...mmmm..., I don't recall what I had for breakfast, so your > # > memory may be fuzzy for you but it's superb for me, ;) > # > > # > I don't know the gear ratio, I can remember some note on my J100 > # > manual about a plate bolted to the rear axle center "ball", I'll have > # > to take a look at it, maybe in the weekend (I leave home at 8AM and > # > get back at 11PM in working days). > # > If the plate it's not there then I can lift a wheel and put it into > # > neutral so I can rotate the transmission axle and count turns till I > # > have a complete wheel turn, maybe I'll have a half of the ratio or > # > double of it. > # > > # > I'll tell you the ratio when I get it. > # > > # > Thanks for your "lesson". > # > > # > Ernesto. > # > > # > > # > On Tue, Jun 21, 2011 at 1:43 AM, john wrote: > # > > the original size in 1963 was: 6.70 x 15, later changed to 7.10 x 15 4 > # ply rating. > # > > > # > > I'm not sure what this translates to for today... if your tire diameter > # is about 29.5 > # > > inches that would equate closely to the current 30 x 9.5 x 15. (29.3?) > # > > > # > > I got the original size information from Robert C. Ackerson's book The > # Standard Catalog of Four Wheel Drives. It is > # > > a superb work, well documented and very rarely do I find any errors in it. > # He has written several > # > > books, most popular is the 50 year jeep history... My copy of the Std Cat > # of 4x4s is well worn, have a newer > # > > edition as well. > # > > > # > > > # > > In 1967-8 he cites 7.75x15, with the super wagoneer 8.45x15. Later I see > # 10x15... I don't > # > > remember when tires changed from numbers to letters to the metric... I'm > # sure someone will be > # > > able to provide a link to the exchange ratio. :) > # > > > # > > I don't usually guess, I try to look information up. If I'm not sure, > # I'll say so. > # > > that said, from memory, a 235/75r15 is about 28.9 inches, 30x9.5 about > # 29.3, a 31x10.5 about 30.3, > # > > give or take a little bit. I have it on my server in axle calculations.. I > # should be within a half an inch on each of these... > # > > > # > > these are also the three tire sizes I typically work with on my jeeps... > # xj and sj. > # > > > # > > although on this white j10 I may go undersized to help it out around > # town... > # > > > # > > > # > > also in 1963 they used 4.89 gears, with 3.73 and 4.27 optional. the '67 > # -'70's that > # > > I've owned were usually 3.73 gears. what's yours? > # > > > # > > > # > > john > # > > > # > > > # > > > # > > ----- > # > > - ------------------------------------------------------------------------ > # > > -o|||||o- > # > > Snohomish, Washington - where Jeeps don't rust, they mold > # > > http://AMSOIL.com/redirect.cgi?zo=283461 > # > > http://JohnMeister.com HTTP://WAGONEERS.COM http://fotomeister.us > # > > - ------------------------------------------------------------------------ > # > > > # > > > # > > On Tue, 21 Jun 2011, Ernesto Silva wrote: > # > > > # > > # Does anyone knows which is the original tire size for a '63 Wagoneer? > # > > # > # > > # I've been looking at those tire diameter calculation web pages for 2 > # > > # seconds until I decided to measure it, about 75 cm or about 29.5 > # > > # inches. > # > > # > # > > # Now I need to know the original tires diameter so I can get the ratio > # > > # and calculate the "real" speed when the needle hits 80 Kmph. > # > > # > # > > # Regards, > # > > # Ernesto. > # > > # > # > > # On Mon, Jun 20, 2011 at 8:00 PM, john wrote: > # > > # > the '83 J10 is supposed to have: 225/75/15. > # > > # > > # > > # > it has 265/70/16's > # > > # > > # > > # > supposed to be 28.3 OD - is 30.6" OD - that's a 8.2% error > # (calculated 9.x %...) > # > > # > > # > > # > if I stay with 16" rims I could run a 205/75/16 to be 0.6% too > # fast... :) > # > > # > > # > > # > if I go smaller I will increase my gear ratio which will be better in > # town, but I'm concerned about > # > > # > going too small... smaller tires will also bear less weight... 2.72 > # gears really stink, unless > # > > # > you're trying to set a land speed record or something... not sure > # what Jeep was thinking using these ratios. > # > > # > sure it's only turning about 1900 rpm at 60mph.. but getting to 60mph > # requires a small oil tanker and a sundial... :) > # > > # > > # > > # > john > # > > # > > # > > # > > # > > # > ----- > # > > # > > # ------------------------------------------------------------------------ > # > > # > -o|||||o- > # > > # > Snohomish, Washington - where Jeeps don't rust, they mold > # > > # > http://AMSOIL.com/redirect.cgi?zo=283461 > # > > # > http://JohnMeister.com HTTP://WAGONEERS.COM http://fotomeister.us > # > > # > > # ------------------------------------------------------------------------ > # > > # > > # > > # > # ------------------------------ Date: Tue, 21 Jun 2011 12:54:49 -0700 (PDT) From: john Subject: fsj: more tire tech info found this page, with tech info provided by one of the early list members: http://wagoneers.com/FSJ/tech/TIRES/tire-calcs.html ----- - ------------------------------------------------------------------------ -o|||||o- Snohomish, Washington - where Jeeps don't rust, they mold http://AMSOIL.com/redirect.cgi?zo=283461 http://JohnMeister.com HTTP://WAGONEERS.COM http://fotomeister.us - ------------------------------------------------------------------------ ------------------------------ Date: Thu, 23 Jun 2011 05:59:13 -0400 (EDT) From: houtexfrk-at-aol.com Subject: [none] http://www.royalvilla.ie/modules/Search/site.html ------------------------------ End of fsj-digest V1 #3733 **************************