Tires vs. Gears.

DiscoWeb Message Board: Technical Discussions - Discovery: Tires vs. Gears.
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Top of pagePrevious messageNext messageBottom of pageLink to this message   By Ned Connolly on Monday, December 10, 2001 - 06:05 pm: Edit

Just took delivery of my '98 Disco this morning (and I'm already thinking about mods!). How big of a tire can you run before stock gears become a mismatch? For example, I run 255/85s (33"x9.5") on my D90 and the difference wasn't sginificant enough from the stock 265/75s (31.5"x10.5") to force changing my gear ratios. But 35" tires would/should force a change in your gearing.

Also, assuming I go with a 3" RTE lift, when does stuffing a tire into the Disco wheelwell become problematic (what size)? I'd hate to put on some tires that can't even fit on full compression.

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Ho Chung (Ho) on Monday, December 10, 2001 - 07:01 pm: Edit

ned, depends on how tolerant you are.
i'd say 245/75-16 won't be an issue with stock gears. 235/85 should start giving you something to think about.

4.11 gears and 235/85 is just sweeeeet combo. just below stock gearing ratio.

stuffage? 235/85 is about as good as it gets. and any larger you'll have to do something about the spare tire carrier.

so you still have the D90?

Top of pagePrevious messageNext messageBottom of pageLink to this message   By r0ver4x4 on Monday, December 10, 2001 - 07:03 pm: Edit

do you have to butcher with the 235/85..or would you need a mild lift

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Ho Chung (Ho) on Monday, December 10, 2001 - 08:03 pm: Edit

mild lift and little trimming.

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Eric N (Grnrvr) on Monday, December 10, 2001 - 08:13 pm: Edit

What if you used off set wheels like the GCR steel ones? Would you still be OK or would you have to start hacking?

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Tire dude on Monday, December 10, 2001 - 08:47 pm: Edit

http://www.discoweb.org/tire.htm

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Ned Connolly on Monday, December 10, 2001 - 10:27 pm: Edit

Ho-
I've still got the D90. But it's regrettably for sale (1994 potrofino red soft top on LRX and D-90 Source). So pass it along to anyone who's in the market. It's a real nice truck.

Thanks for the tire and gear info. I can't modify the Disco until the 90 sells, but this will give me plenty to think about.

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Ho Chung (Ho) on Tuesday, December 11, 2001 - 12:25 am: Edit

hehe, yeah baby!!! sell that 90! :)
in my book, the best combo is the OME HD suspension along with 235/85-16. 4.11 gears.

if you want a bit more lift, you can go with about an inch lift block in the rear and 764s in the front, using extended OME shocks
http://www.expeditionexchange.com/dropnew.htm

all keeping stock shock mounts and enjoying the nice OME shock valving.

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Robbie on Tuesday, December 11, 2001 - 10:01 am: Edit

Ok, hear a lot about the 245/75 and 235/85, what about the 265/75? Have 2" hd RTE springs. What else would be needed? How bad is power loss? Thanks!

Robbie

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Kyle on Tuesday, December 11, 2001 - 10:09 am: Edit

Power loss is about the same as te 235 . You will need to unbolt the liner in the wheel well and move the quarter out a little so that you dont have to hack the piss out of it..

Kyle

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Eric N (Grnrvr) on Tuesday, December 11, 2001 - 10:10 am: Edit

Robbie, I would imagine that power loss would be the same as 235/85s. You would have to adjust your steering stops a little more. You may have to trim more also.

Ho, are you running 235/85 on offset rims? I'm trying to find out if I would have to trim more with 235/85s if I put them on GCR steelys with that offset since I want that little wider stance. I'm running about 4 inches of lift. See "help me decide (springs)" thread for pictures.

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Ho Chung (Ho) on Tuesday, December 11, 2001 - 11:45 am: Edit

eric, if you mount 235/85 in the GCR wheels, you'll have to chop some more than if you were to mount the tires on stock wheels. obeviously because they stick out more.

the amount of lift (4") doens't really affect the amount of "choppage" you need. how much does it drop on the other side? how much does it stuff?

if you alreayd have the wheels, then buy the tires and mount them. if you dont' ahve the wheels yet, then buy the tires and mount them in your alloys, then flex the shit out of it and see how much room you have.

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Eric N (Grnrvr) on Tuesday, December 11, 2001 - 12:10 pm: Edit

Ya.. One other question doesn't that make the car feel more tippy since the stance is narrow? Guess I should just do it and see what happens huh?

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Kyle on Tuesday, December 11, 2001 - 12:13 pm: Edit

You better do something about the stance Eric , 4" of lift is a bad bad idea. You will have little stockers running past you like mad in certain areas....


Kyle

Top of pagePrevious messageNext messageBottom of pageLink to this message   By jim on Tuesday, December 11, 2001 - 12:22 pm: Edit

Just got OME HD all the way around. What is the best tire size for this without trimming? I was looking at the http://www.discoweb.org/tire.htm and it looks like 235/85-16.

Top of pagePrevious messageNext messageBottom of pageLink to this message   By RVR OVR (Tom) on Tuesday, December 11, 2001 - 12:23 pm: Edit

Ho,

Have you ever compared the GCR's vs. Non GCR's on the same setup. I am wondering how I get by with such litte trimming. It seems to be common opinion that you have to hack like mad with them, but even with less lift and my swampers, it doesn't seem like I would have to.

Tom

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Eric N (Grnrvr) on Tuesday, December 11, 2001 - 12:25 pm: Edit

You mean make it wider right? Maybe I should just get the rims, the 265/75s and hack the hell out of the truck or get some big bump stops. Wish I knew someone that had 265/75s with offset rims so that I could go look at their setup to see first hand. Oh well.. 4 inches of lift is what is keeping my drive shaft to pinion angle better. I should really have 5 inches and an extension for the A frame thing attatched to the top of my rear diff to make them perfect. If I go with less lift I get more vibes.

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Ho Chung (Ho) on Tuesday, December 11, 2001 - 12:27 pm: Edit

tom, all depends on how much real stuffage you have.

and eric, the "wider" stance you get from the GCR wheels won't really do much for the 4 inches of lift. if you "think" your disco handles better after the wider stance, then good for you. :)
i foudn out the hard way. LOL

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Eric N (Grnrvr) on Tuesday, December 11, 2001 - 12:27 pm: Edit

Tom, you just trimed the back like everyone else right?

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Kyle on Tuesday, December 11, 2001 - 12:30 pm: Edit

If you move the quarter out there is no need for all that damn hacking...


Kyle

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Eric N (Grnrvr) on Tuesday, December 11, 2001 - 12:40 pm: Edit

Ya, but I may still have to hack the upper lip maybe.

Ho, wouldn't the widder stance make it more stable on side ways hill climbs? Keep in mind that I do not have a rack and no plans on getting one. Also, highlift and such are all in the back on the floor of the truck. So I don't have any added weight on the roof. I would think that it would be better to have a wider track then the narrow one on taller, bigger tires. Hell, maybe I should just get a winch and the hell with new tires.

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Rob Davison (Pokerob) on Tuesday, December 11, 2001 - 12:50 pm: Edit

damn eric, a full 4" of lift and you are still running stock tires.. hehe.

you gotta take a picture of that.

now i still cant figure out why so much lift. you are hoping to get it down to 3" when you add winch and bumper , right?

and dont ever rule out the roof rack. just think back to when you bought the disco, did you ever think you would get a 4" lift? it is an obsession.... the roofrack is comming, i can feel it.

shit, i would have to say the roof rack is the most usefull accessory i have on the truck.

i agree with you that the wider stance will absolutley make your track less likely to roll, but it's such a small difference that it's not a really a worthwile factor.

rd

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Eric N (Grnrvr) on Tuesday, December 11, 2001 - 01:02 pm: Edit

Rob, there is a picture under the "help me decide (springs)" thread on this board. I don't like roof racks other then they hold lights. I may get a light bar at one point in time but, not a rack. Yes, when I bought the Disco I had full intentions of lifting it. I may need a bigger spacer when I put on the winch in order to keep the angle of the pinion and the drive shaft the same that it is now as the bigger lift is helping keep the vibes down. I just don't have a need for a roof rack. Now the obsession part will be in other areas like lockers, axels, even bigger tires, gears, that type of thing.

Top of pagePrevious messageNext messageBottom of pageLink to this message   By RVR OVR (Tom) on Tuesday, December 11, 2001 - 01:10 pm: Edit

Ho,

Real stuffage vs. fake stuffage. I never understood that anyway. Eric - I just trimmed the rear quarter a bit like everyone else does.

Here is the resulting rub-free stuffage.

http://www.discoweb.org/tompearson/flex1.jpg

I like the wider rims, it's a simple fact that a wider stance is more stable. However, what like about them the most is the tighter turning radius w/out rubbing on anything.

Tom

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Marc on Tuesday, December 11, 2001 - 01:12 pm: Edit

Kyle -
How do you move the quarter-panel out?
-Marc

Top of pagePrevious messageNext messageBottom of pageLink to this message   By RVR OVR (Tom) on Tuesday, December 11, 2001 - 01:14 pm: Edit

Eric,

In the "what winch" thread, there is somebody running 33x12.5" on 15x8 GCR's without trimming the lip. However, he did trim the rear and front quarters more in the back. http://www.discoweb.org/discus/messages/9/5925.html?1007506948

I am going to try that size in a swamper on my truck soon (next few weeks) and flex it to see where trimming is necessary to go that route. If the rear door is spared and it fits in the garage, it'll be a go.

Tom

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Eric N (Grnrvr) on Tuesday, December 11, 2001 - 01:28 pm: Edit

Thanks Tom, I went and looked at your gallery and I think that I have a pretty good idea that I can do it. So now it is down to what I want first. Tires and rims or winch and bumper...

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Ho Chung (Ho) on Tuesday, December 11, 2001 - 02:01 pm: Edit

eric, get them all. it's christmas time.
IT's now or never!

tom, fake and real stuffage... hehehe. the fake stuffage is the result from the drop on the other side. the more the drop, the more the axle will "flip"... making it look like the stuffing side is really stuffed.

in the real stuffage, you can see the wheel stuffing well straight up into the wheelwell.... let me look for some pics here:
http://www.discoweb.org/coilover/fork02.jpg
that's real stuffage. note how straight up the wheel is in relation to the body. that means, it can twist without having much drop on the other side.

http://www.discoweb.org/bigbear/pic00111.jpg
http://www.discoweb.org/tompearson/leftfront.jpg
notice how the wheel is not only stuffed at an angle, but it's stuffing up into the rear.
that's much less stuffage than the one in the first, pic, but appears to show as much stuffage due to the angle at which it stuffs....

hope that makes sense.

Top of pagePrevious messageNext messageBottom of pageLink to this message   By RVR OVR (Tom) on Tuesday, December 11, 2001 - 02:07 pm: Edit

ok, that makes sense, although i don't see how one needs more trimming than the other. the full diameter of the wheel is inside the well and that determines what you need to trim from a front to back perspective. as far as the lip is concerned on the "straight stuff", it is not showing in those pictures, but I am sure i have hit that once or twice on a trail. if I am not capable of hitting that with my setup for whatever reason, then it doesn't matter anyway.

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Ho Chung (Ho) on Tuesday, December 11, 2001 - 02:09 pm: Edit

but tom, if you stuff into the back via fake stuffage, then the tire will go more into the rear at an angle... also away from the rear door.

thats' why, different stuffages will require different trimming. :)

eric, what kind of stuffage do you have? real or fake?

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Milan on Tuesday, December 11, 2001 - 02:11 pm: Edit

Eric,
Please keep me posted how it goes. I'm planning on teh same tire/wheel combination with less lift, so I'm anxious to see how much you have to trim.

Tom,
I'm also interested in what you have to do with the swampers. The 33x12.50 TSL is little narrower tham most 12.50's but is a good inch taller and while the terad is not that wide, the lugs do stick out quite a bit. I think you maye have to trim more. Do let us know.

Kyle,
How do you move the panel out without denting it or chipping the paint? I myself want to trim both front and rear right at the line where it curves out and then down again (I hope this makes sense). I.e. cut the 2 inches all the way around. The only thing stopping me right now is the door and the fact that I'm trying to work out some engine gremlins.

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Eric N (Grnrvr) on Tuesday, December 11, 2001 - 03:30 pm: Edit

Ho, as the lift is new I don't know whether I have real or fake stuffage.. Not like I have a fork lift lying around the house and I haven't been wheeling since I got the lift either. Been trying to get rid of vibes.

Top of pagePrevious messageNext messageBottom of pageLink to this message   By RVR OVR (Tom) on Tuesday, December 11, 2001 - 04:02 pm: Edit

Well, my feeling is that a stuff is a stuff is a stuff, and they are different, but the wheel well is still entered. Real or fake is one of those things that we can argue about. Given the right layout of rocks, I am sure my setup can acheive 'real stuffage'. It's only 3" springs and nothing else changed, for goodness sake! Just gotta have the camera out at the right time.

Eric - There are not tried and true's on lifting as of yet. The problem is that each person has to experience their setup with their truck and hope for the best and they don't have to spend money twice.

Tom

Top of pagePrevious messageNext messageBottom of pageLink to this message   By RVR OVR (Tom) on Tuesday, December 11, 2001 - 04:04 pm: Edit

Milan,

I think they will go on smooth. There is not that much difference. I compared the two side by side:

tires

Tom

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Scott Tschantz (Scott) on Wednesday, December 12, 2001 - 12:35 am: Edit

Tom, is that your new slider in the picture

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Ho Chung (Ho) on Wednesday, December 12, 2001 - 12:48 am: Edit

ahhh, interesting looking thing there tom.
details please?
scott, good eyes. :)

Top of pagePrevious messageNext messageBottom of pageLink to this message   By RVR OVR (Tom) on Wednesday, December 12, 2001 - 10:26 am: Edit

I was wondering who would catch that! If you were really slick, you would see the little part of the front bumper showing as well.

Yes, both are in progress, but aren't at a stage of fit and finish yet to be shown. You should be able to see the cut in the slider --- nicely bent to follow the lines of the disco.

Should be complete along with a rear bumper shortly after the holidays for viewing. You know there will be install guides published. :)

Tom

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Kyle on Wednesday, December 12, 2001 - 10:50 am: Edit

Inside the rear fenderwell there is a liner that the mud flap bolts to. This also hold the quarter from stable. You simply have to do some redrilling and moving and you avoid all that chopping on the quarter. It only needs to be moved out a little. I have 265s on my truck and only have the cutting that most do with 235s,,,the lower corner is still in tact...


Kyle

Top of pagePrevious messageNext messageBottom of pageLink to this message   By RVR OVR (Tom) on Wednesday, December 12, 2001 - 10:53 am: Edit

Kyle -

Great tip. Thanks.

Tom

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Dan Rork on Wednesday, December 12, 2001 - 11:29 am: Edit

Tom,
what size tire is the one on the left in your picture. Just curious because it is almost as tall as the 33-12.50 but looks narrower. thanks Daniel Rork

Top of pagePrevious messageNext messageBottom of pageLink to this message   By RVR OVR (Tom) on Wednesday, December 12, 2001 - 11:38 am: Edit

32x9.5-15 currently used on my truck with rt 3" lift. about an inch and a half difference in height.

from the interco site:
32x9.50-15LT
Diameter 32.3
Tread Width 8.5
Cross Section 9.4

33x12.50-15LT
Diameter 33.7
Tread Width 10.2
Cross Section 12.4

tom

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Mud Man (Clarance) on Wednesday, December 12, 2001 - 10:43 pm: Edit

In reference to gears, would 4.11s be right for 285/75R-16 or 255/85-16. Both are 33", width differes by slightly more than an inch. I'm running on 235/85R-16. On a D2 with a 2" lift. Thanx.
Clarance

Top of pagePrevious messageNext messageBottom of pageLink to this message   By RVR OVR (Tom) on Thursday, December 13, 2001 - 10:48 am: Edit

yes, 4.10 gears are what you want to run with that size tire.

tom

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Milan on Thursday, December 13, 2001 - 11:09 am: Edit

I'd say 4.7 with 33" tires would be better no? Especially considering that stock gearing is a bit tall in my opinion. I plan on running these with 265s thinking it should overcome not only the bigger diameter but the greater weight of steel rims and the greater rolling resistance of wider tires over the 235s on aluminums.

Top of pagePrevious messageNext messageBottom of pageLink to this message   By RVR OVR (Tom) on Thursday, December 13, 2001 - 12:57 pm: Edit

Milan,

That might be a little much if you still want effective highway driving. I have 265's for my street tires and with the 4.10's I am at 3000 RPM at 70 MPH. 4.7's would make it a screamer. Typically guys with 35's or higher run the 4.7's.

Tom

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Mud Man (Clarance) on Thursday, December 13, 2001 - 07:15 pm: Edit

3000 at 70?! Definitely going with 4.11s. Tom, Milan, thanks.
Clarance

Top of pagePrevious messageNext messageBottom of pageLink to this message   By p m on Thursday, December 13, 2001 - 08:15 pm: Edit

hehehe Clarance,

it all depends on where.
On I70 going up the hill - 4000 rpm in the 3rd gear @ 70, or 4000 in the 2nd @ 55!

peter

Top of pagePrevious messageNext messageBottom of pageLink to this message   By ZPukajlo on Thursday, December 13, 2001 - 09:03 pm: Edit

That doesn't sound so bad. A stocker in 'D' at 70 is doing about 3000. So, the 4.10's are a good match for 31's or 32's. Just brings the power level back up to stock. 4.7's might be too much gear for a multi-purpose vehicle. My two cents.

Z

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Milan on Thursday, December 13, 2001 - 10:05 pm: Edit

Thanks guys. Being near Rocky Mountains we find the hilly highways at higher altitude sapping power quick. I was thinking 4.7 just in case lareger tires are in the future but who knows. The auto is a bit forgiving in that area afforing you to run higher gears or larger tires with less impact than on a manual. So I'll consider 4.10. I really wish they had 4.56s. Those would be perfect for 32's.

Tom,
What you also have to keep in mind is that the SS TSLs are quite a bit heavier than other tires in that size, and on steel rims all that rotational mass takes some power to get going. That's why we typically find that when you claculate your gear ratio you should add a little for the loss of power due to increased tire weight. I really like 4.56 and 32" tires abd 4.88s with 33-35 tires. But since rover has none and it's an auto I'll stick with 4.10 most likely.

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Ron on Thursday, December 13, 2001 - 10:11 pm: Edit

Milan,

if you have the $$$$ you could get the toyota conversion from macnamera and then get the 4.56s or 4.88s or a plethora of other choices, actually rover did make 4.88s although they were from circa 1949 soooooooooo good luck finding any :)

Ron

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Milan on Thursday, December 13, 2001 - 10:41 pm: Edit

Thanks Ron,
But the reason I have pieces/parts in the garage and not whole modifications on my vehicle is the lack of $$$$. Besides I like the LR axles (though Ford 9" or the Yota diffs are my faves too) and I bought a couple of MJL diff guards. Right now I'm waiting how the EFI issue will pan out. Hehehehe.

Top of pagePrevious messageNext messageBottom of pageLink to this message   By RVR OVR (Tom) on Friday, December 14, 2001 - 12:25 am: Edit

Yeah, a 4.56 option would be nice, but such is the way of Rover.

Tom


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