[Pete087]

Hi guys, I have a 91 sierra that I am in the process of building. I have an X90 (96) as a doner vehicle, which (besides front end damage) is in pretty good cond so am looking to get anything I can off it to make the sierra a better 4wd. It won't be a daily so within reason I'm not too concerned about comfort etc just want it to go as many places as possible within some form of budget.
Heres a breif run down on what I've got and what my intentions are: G16b conversion (I have bought the BenT adapter), I havealso bought a turbo that came off an sr20 (but will be running minimal boost), I want to run lockers, 31s and am still weighing up my options with suspension/lift (thinking 2inch suspension possibly SPOA and 2 inch body). I would like to run the discs brakes off the x90 aswell as the diffs etc (is this worth doing?) and anything else I can/should nick off it. Any advice/corrections would be greatly appreciated!! Cheers Pete

[Trypt]

IMO SPOA and 2 inch body would be VERY sketchy without lux diffs.

I have 2 inch spring lift and thats plenty enough for 31's

With lockers, 2 inch lift and 31's you will go just about everywhere short of climbing a tree... but hey if ur talented enough you might get up a tree

[Pete087]

Hahah nah no talent mate thats why I need the car to do the hard work Do you recommend your springs?

[stewy91]

If you go and do all that work and can't drive good you will just end up getting stuck somewhere you should not be.

[appsie]

i think if you pulled up at the 2" springs and 2" bodylift with 31s,geared and locked with the 1.6 efi and power steer you would have the perfect zook. spoa on its own with no other lift would be acceptable but still not great,only benefit is going to be losing your fangs on approach to obstacles.

ive pretty much had the zook mentioned above and loved it,was simple,worked and most of all always a fun day out in it.if the x90 runs a steering box like a vitara pinch that and you are on your way

[SierraDan]

Agreed! ^

[Pete087]

Thanks for your response mate. A few forums have mentioned that the x90 is just a short wheel base Vitara underneath so hopefully the steering is the same. Is there alot of work in swapping that? The other thing my research has stumbled accross is the vit diffs have a better ratio when running the bigger tyres so do you think using them will suffice or will I have to reduce the TC aswell? I wouldnt mind the revs down a bit for highway driving and am hoping the extra powe from the 1.6 ans turbo should be able to spin them ok? thanks again for any help

[appsie]

zuks love to rev. having them sit on 3600ish up the hiway aint a bad thing especially when running a 31 etc.i had 31s and 6.5 transfer gears and it was around 3700 from memory,at times you would definately not want it to be any less.

your right the manual vits had 5.12 ratio and auto had 4.6 as opposed to a WT sierra 3.7. i dont know what an x90 would have. and only the front centre will be of use to you unless you done a whole rear diff swap which could me a major job.

the power steering should only be as much as getting a benT adapter wedge and going from there

[Pete087]

Hey mate thanks again for your help, I'll start researching the power steering now from what I can gather the diff ratio in the x90 is 4.62 (it's manual but they seem to be slightly different between the 8v and 16v donks) I suppose I'll just attempt all the calculations to see what the benefit is and which way to go. You don't recommend the diff swap? Does anyone know how much the 31s brings the revs down in 5th without changing anything else? Cheers Pete

[mr.green]

i had 31s and no gearing for a couple of years. the drop on rpm at 100 made 5th gear pretty much redundant. but this was back before the world shrunk and gears cost $1300 odd. if i was going down that path it would be spoa on standard springs, ruf if you get excited enough, grab the ps from the x 90 buy the 6.5s from the usa, air lockers from china and Go!

[appsie]

i ran 5:12s with 31s and a standard 1.3 motor. made it driveable on the road but offroad it was no where near enough gearing not for the sort of driving i like anyway.
6.5s cant be beat imo,makes a sierra more useable than anything else for the $$

[Pete087]

Thanks heaps for your input guys I appreciate the help! Because of all the things I'm trying to do to the poor girl, the budget is forcing me to compromise! I'm kind of hoping the g16b and turbo will compensate for the 31s without having to alter the gearing as although its not a daily I hate listening to her on 4k revs for hours when traveling

[Fatzook]

Pete087 wrote:

Thanks heaps for your input guys I appreciate the help! Because of all the things I'm trying to do to the poor girl, the budget is forcing me to compromise! I'm kind of hoping the g16b and turbo will compensate for the 31s without having to alter the gearing as although its not a daily I hate listening to her on 4k revs for hours when traveling

I'm not sure it will. Power is almost never an effective means of overcoming incorrect gearing. Besides, the money you spend turbocharging the G16B, will more than pay for a reduction gear set.