[mike86]

Hi guys

Just recently acquired a very clean 1988 WT hardtop completely stock. Took me about 12 months to find one but eventually found something in great nick for the money.

Anyway the suspension was sagged so i've put a 2 inch OME lift in it with commodore/Highace shocks.

Next on the list are some wheels.

What i had in mind were 15x8 -23(ish) offset with 31's to start with so the stock gearing isn't horrible but will also be ok when i fit some crawler gears. Then once they wear out i'll shoot for 33's (if needed)

My questions are
1) Are 15x8s the go or should i just go for 15x7s? I'll be mainly doing tame rock climbs like mt walker (NSW) and beach stuff.
2) is -23 offset ok or will i need to cut out the factory flares. I dont mind adding flare extensions but dont want it to rub when flexed up.
3) What type of wheels should i get. so far i like sunnies or procomps.
4) can anyone recommend places to get a great price on wheels+tyre combos. dont mind ordering out of state if it's cheaper. I'm in NSW.

Thanks for your help guys. I'll post up a build thread when i have some time and stuff worth posting.
Cheers
Mike

[pezz]

Personally id go 15x7's in a sunny

[Gwagensteve]

X2. 7" rim for a 10.5.

Rim design and material is really up to whatever you have budget for and like the look of.

You're going to want gearing with 31's. 31's on stock gearing sucks.

Steve.

[mike86]

Does the stock gearing suck to the point of needing transfer gears straight away? or is it just annoying and not ideal?

What the reason for going 15x7's over 15x8's? Wouldnt there be a benefit of wider tyres?

[Gwagensteve]

Tyres stay the same width regardless of the width of the rim. Putting a 10.5" wide tyre on an 8"'rim makes the tyre more likely to fall off when aired down, it makes the rim more vulnerable to damage, makes the tyres harder to cover wih flares, makes the wheels harder to fit, but offer no performance benefits.

The gearing will be pretty terrible. It will be JUST ok on the street, but you won't see 5th gear much unless you're heading downhill. Off road, you'll be killing the clutch and you'll have to hit everything far too fast to prevent the car stalling. Unless you exclusively drive sand, 31's need gears.

Steve.

[mike86]

Thanks Steve

Appreciate the feedback. New to zooks. Hence why I posted in the noob section. Guess ill have to try get gears at the same time. If that's the case shoukd I be looking at a bigger tyre (33s perhaps) and go woth the 6.5 gears. Or are 31s a good size for most typres of 4wding?

[Blkfxx]

31s will be fine with 6.5s, Plenty of people on here run that combo.

If you are fairly new to 4wding then there's no need for 33s.

[Gwagensteve]

And 33's are much more work to fit, and much harder on the driveline than 31's.

33's also perform poorly in some off road situations due to inadequate ground pressure.

Steve.

[pezz]

If your unsure of what tyres to choose, why not add 30x9.5 into your options...
I had 31's and 33's on my old zuks, but i was happy to drop back to a 30" to get a skinnier tyre again...
Personaly i think sierras archs were made for 30's

[sideways]

pezz wrote:

Personaly i think sierras archs were made for 30's

They pretty much were, largest stock tyre was a 6.50x16 which is 29.65". They were fairly skinny and had a very rounded profile, hence why a 30x9.5 fits a stock Sierra just fine until you turn when flexed up.

If you're new to sierras (and especially if you're new to wheeling) and wheeling I'd suggest fitting some 235/75r15 mud tyres, a rear locker, some 4.9:1 transfer gears and some rock sliders. From a newbies perspective it will go pretty much anywhere and it will be more capable than the driver.

The need for big tyres is kinda over rated. Also, you'd never get anywhere near the potential of 33s if you wanted to keep a hardtop body in good condition.

[tmitchell]

I'm running 31's with 6.5's on my Sierra and I reckon thats about ideal. Aired down to 15 psi for off road, but could do with less if doing a lot of rock crawling.

Edit to add: it was a lot better behaved on road with 30's though.

[whincup]

definitely no need for 33's. sierra diffs with a 31" tyre gives slightly more ground clearance than a GQ patrol on 33's.

[Collard91]

sideways.
I like your comment on what to run being new.
I myself am new.
so is there any need for a lift? At the moment im running 27.7 8.5 so stock. is there any need to upgrade tyre at the moment?

[Marko_SJ]

I have seen 7.50 r16 on LJ wheels fitted to a sierra.

Fit fine, although would need bump stopping. It would get good clearance and still maintain ground pressure?

[Blkfxx]

Marko_SJ wrote:

I have seen 7.50 r16 on LJ wheels fitted to a sierra.

Fit fine, although would need bump stopping. It would get good clearance and still maintain ground pressure?

The majority of 16in tyres have a higher load rating.