[OMalley]

Wanting to gear my new coily to suit the 31"s I have sitting in the shed. (they measure a 30.5" though)

Will be using a WT transfer and front jackshaft to do this.

The zook will be used as a daily driver So it needs to be able to sit on 100km/h but still be able to turn it's new shoes over in the bush.

I was thinking either 4.9 or 5.12 transfer gearing but can't make my mind up.... Thoughts?

Thanks in advance

[tanshi]

IMHO 5.1s will be too low for 31s

i used 4.9s with no issues at all.

[OMalley]

tanshi wrote:

IMHO 5.1s will be too low for 31s

i used 4.9s with no issues at all.

Yeah that was what i was worried about, would rather go 4.9's anyway i think. They're cheaper too..

The diff ratios of a coiler a lower too yeah? which would help turning the 31's over?

[tanshi]

diff rations of a coiler are 3.9s, so they are lower gears.

but yes the do make them turn tires better

[OMalley]

tanshi wrote:

diff rations of a coiler are 3.9s, so they are lower gears.

but yes the do make them turn tires better

Yeah, that was what i meant

4.9's sound like the go i reckon

[zooktastic]

i used 6.5s with 31s and 3.9s in my WT and it seemed to go well enough, happily did 100kph and crawled well offroad.

[tanshi]

yeah 6.5s will work, but they are not ideal. you would be doing 3800 revs at 100 in 5th

[Teracis]

Anto86 is still running 29's with his 6.5's, it's definitely revving along the highway :p

Mine's the same but WT so it's not revving quite as high.

[masterA]

Instead of posting a new thread....(and sorry for hijacking this one)

My tyres are 30x9.5 Maxxis Bighorns and i'll soon have a GTi engine in there (its a 92 hardtop sierra WT).
Was considering getting the 6.5's as they are cheaper then both 4.9 and 5.12 but what would ultimatelly be better?! (tanashi....what would you suggest...do you know what RPM would be doing with 4.9's as opposed to 5.12s or 6.5s?!)
It will definatelly be driven on road and needs to do 100km comfortably but don't want it to be a pig on the bush either?!

[zooktastic]

it wasnt revving that high for me, but hey its only a small motor so revving it wont be that bad.

[tanshi]

masterA you will be doing 3700 at 100kms.

bit too high for my liking.

[captainattractive]

Hmm, how does that work. I have a stock wt transfer case in my leaf Sierra and at 100km/h it's revving at 3600 in 5th? I have the stock 205/70r15 tyres on it too...

[Gwagensteve]

I think anything under 4K is acceptable.

Stock is 3550ish @100, but bigger tyres have higher rolling resistance and the suspension lift that often goes with them adds aerodynamic drag, so it doesn't hurt at all to be spinning a bit harder to compensate.

Stock jimnys are over 3900 IIRC.

Steve.

[taszook]

yeah i do 37-3800 with 30's and 6.5 and a stock 1.3. think they work well, still has no power so the extra revs help on the highway. can sit on 100 on a flat road, any hill and it slows down

[stockman]

I wouldn't waste my time on anything other than 6.5's. As others have said the little 1.3 is going to struggle in 5th gear at a low rpm, so why not sit on a higher rpm.

Mine will sit on 110 in 5th (unsure of the rpm) and as soon as I hit a hill I'm back to 4th. Imagine what it would be like with higher gearing.

[zooky08]

Since your on a role tanshi, can u work these out please
Rpm at 100km for:

1.6l, 30's with 4.16 and 3.9 centers.
1.6l, 30's with 6.5 and 3.9 centers

Cheers

[SierraDan]

As far as I'm aware 4.9's have the same high range as a 1ltr case?

I have a 1ltr case with 31's and it's horse shit to drive.

[tanshi]

its a personal choice.

i would never have a car running at 4k at 100. specially if you ever intend on putting a 1.6 in it.

[OMalley]

Starting to swing to 5.12's now (just dont like how they are more expensive)

Not going to go 6.5's though thats too low geared I feel. At least for daily I feel it is, but thats just my opinion.

Will have to sit on it for a bit.

[brodie03]

Sorry for the hijack, I read on an american website quoting a suzuki webpage, that the coily's have a slightly higher gear ratio then a wt sierra. Is this the case?, as the OP will need to factor this in slightly during calculations.

Edit: I think I worked it out to be around 6% difference (unsure if this was low or high range or overall)

[neofitou]

I had 31s (30.5s) with the 6.5s and loved it.
Prior to that I had a 1l case and it was not nearly as good.

ATM I have a Dana transfer case.. And I cry. A lot.

But hopefully for not much longer!

[OMalley]

Thanks for all the info everyone, BUT, Keeping in mind its a daily driver, and its a coily with lower 3.9 diff gears, and the fact I dont want it to be revving its tits off down the highway.

Do you feel 4.9 transfer gears would be a good choice for decent all round performance with 31's (30.5)?

Cant make my mind up...

[SierraDan]

Yes.