Effect of larger tyres on an rb30's performance.

[mudnut]

I was going to fit rocksliders to my wagon, but a mate reckons that larger tyres would be a better first investment. Has anyone with an rb30 fitted 32" tyres?
I'm only getting 70 kw on the dyno, so there is not a lot of torque to play with. Is fuel economy and towing affected?

[taslucas]

I doubt you'll even notice a difference putting 32s on. Personally I'd got for 33s straight up. I have a mate with 33s on his rb30, four wheel roost no worries. Another mate had 35s and while you lose a little bit of power, it still went fine. Kept up with my TB42 (33s), and others GU 2.8s (33s) easy. On fast gravel driving.

Tap, crackle, pop

[taslucas]

Just uses a bit more fuel the bigger tyre you go...

Tap, crackle, pop

[mudnut]

If you go 33", what suspension and steering components need to be upgraded so as not to rip into the guards? My pockets are not deep.

[threedogs]

It will effect your braking as well, thats a lot of tyre to try and pull up, a big rolling mass.
Bearings get extra pressure put on them as well but cope ok.

[GQ TANK]

What size do you have at the moment.

the old split rims - R750 R 16 are 32 "

[Steve4wdin]

It will effect your braking as well, thats a lot of tyre to try and pull up, a big rolling mass.
Bearings get extra pressure put on them as well but cope ok.
Question,why would there be extra presure on bearings. I would have thought less presure on bearings as they are not having to spin as fast. Yes a bit extra weight. I guess thats just the fitter and turner in me. For eg. boat trailers with small wheels verse big wheels. You have a lot more problems with smaller wheels???

[threedogs]

They are a lot wider but only marginally, and 7.50 x 16 is a 33 in diameter tyre

[mudnut]

What size do you have at the moment.

the old split rims - R750 R 16 are 32 "

i've only got the factory 15" with 31" 10.5 road tread.

[healy]

I've got an rb30 carb I was running 31x10.5r15 no worries now I'm on 35s just have to get some 4.6s put in and your power stays the same from my experience

[threedogs]

That means you have 10.5" wide tyres on 15" rims and 31" diameter
you may need a 2" lift if you don't already to run 285 x 16 {33"]
or 33"x 12.5" x 15

[mudnut]

Sorry, Healy. What is 4.6s?

[taslucas]

Sorry, Healy. What is 4.6s?

Thats the diff ratio. If you change the diff ratio, you can counteract the larger tyres. Different model patrols come out with different diff ratios so you can easily swap them to change the gearing of your patrol.

[GQ TANK]

Threedogs 7.50 x 16 are 31.64" in diameter tyre same diameter as a 265/75/16 = 32 inch

31 /10.50 r15 are 31 Although my 31/10.5r15 mongrel muddies with the extra rubber are the same sive as my 7.50 R16 and 265 /75 r 16 tyres

See http://www.1010tires.com/tiresizecalculator.asp?action=submit

[mudnut]

Threedogs 7.50 x 16 are 31.64" in diameter tyre same diameter as a 265/75/16 = 32 inch

31 /10.50 r15 are 31 Although my 31/10.5r15 mongrel muddies with the extra rubber are the same sive as my 7.50 R16 and 265 /75 r 16 tyres

See http://www.1010tires.com/tiresizecalculator.asp?action=submit

That's some serious tread, they must sing at 100 kph.

[MQ MAD]

Goin to a 32 " or equivelant isnt worth the effort, go to 33 " as mentioned,if your buying new boots
Itll change the low down pick up compared to a 31 " as the car will be quicker of the mark with the smaller tyres
7.50x16 is a factory option on the GQ as is the TI style 16 " mags,so any of those factory sizes shouldnt need any guard choppin ....
Changing diff ratios, well youll need to source the relevant diffs, get new gaskets, seals, new oils,few beers as well, so that can cost

The sky is the limit with mods, but the wallet will tell you what youll get

[97_gq_lwb]

If i had an rb30 patrol the first mod would be an efi turbo conversion.

[GQ TANK]

The mongrels sound like a plane landing at 100km, but awsome in the mud.

I saw there a mob in sysdney doing mongrels on ebay ( where around $500 for a set of 4)

[Rustyboner81]

whats involed with the efi turbo conversion? i too have rb30 carby duel fuel lpg/petrol. can you have a turbo'd LPG engine?

[97_gq_lwb]

Yes you can run gas but it can cost a little more a gas research throttle body would be my choice.
their are other threads on turbo efi conversions.

[Rustyboner81]

cool i will find them

[mudnut]

If i had an rb30 patrol the first mod would be an efi turbo conversion.

Well, for one, I happened to pick up my old trol because I happened to be at the car yard as it was just traded in. Two, I've had a small efi 4wd break down, and it cost $$$$. I have a chance of fixing a carby if it stuffs up. (Had the second stage stick shut, but I got it working enough to get home. Converted an old Mitsubishi auto advance to fit, until I got the original rebuilt.) And three, Ive had three mechanics praise the RB30, as pretty well unbreakable. The downside is parts are harder to come by. I'm having trouble getting a hub nut socket, cause the 54mm has a 67mm outer diameter, and I need a socket with 63 mm maximum i know a drift can be used, but i don't like the Idea of metal shards getting into the bearing.

[97_gq_lwb]

Heres a hub nut sockethttp://www.ebay.com.au/itm/Nissan-Patrol-4x4-GQ-MQ-Hub-Nut-Socket-54mm-1-2-Drive-/350587136623?pt=AU_Car_Parts_Accessories&hash=item51a09f2a6f
I bought mine locally at bolt master but any decent tool shop should have one.

Or you could go for the upgrade they call a gu socket wich actually came out on gq's lol
http://www.ebay.com.au/itm/GU-Hub-Nut-upgrade-Y60-GQ-Nissan-Patrol-INC-1-2-HUB-SOCKET-/290763623135?pt=AU_Car_Parts_Accessories&hash=item43b2dccadf

[Rustyboner81]

http://www.ebay.com.au/sch/i.html?_nkw=54mm+socket

yeah same, i ordered 2 one for me and one for my mate caz i couldn't find them in any tool shop. stores that did supply them where out of stock from about 12 months ago.

ebay is hevan for gq stuff. i just got an original undamaged interior light cover for mine. sooo pleased with myself.

just check, some hub nuts are 3/8" drive some are 1/2"

[mudnut]

Heres a hub nut sockethttp://www.ebay.com.au/itm/Nissan-Patrol-4x4-GQ-MQ-Hub-Nut-Socket-54mm-1-2-Drive-/350587136623?pt=AU_Car_Parts_Accessories&hash=item51a09f2a6f
I bought mine locally at bolt master but any decent tool shop should have one.

Or you could go for the upgrade they call a gu socket wich actually came out on gq's lol
http://www.ebay.com.au/itm/GU-Hub-Nut-upgrade-Y60-GQ-Nissan-Patrol-INC-1-2-HUB-SOCKET-/290763623135?pt=AU_Car_Parts_Accessories&hash=item43b2dccadf

Yeah thanks, but I rang the shop and had him measure the outer diameter for the hub nut tool... too big.
Are the gu upgrades compatable with the 63mm hub? I've tried the tool joints within an hours drive and haven't come up trumps yet. One bloke suggested getting a socket and machining it to fit but the corners were recessed too deep too machine.

[97_gq_lwb]

Did you take the spacer out ?

[mudnut]

that could be my problem. didn't see it through the grease and stuff. The smart.... at the dealership must have had a laugh at my expense when I asked about a genuine socket