1uz 4x4 - how to get more low down torque?

[Robbos_Toyotas]

Hey all, have bought myself an 81 dual cab 4x4 hilux to have some fun off road with. Now i do plenty of steep crawls/ rock crawls/ mud etc etc where i need plenty of low down torque...
unfortunately i cant put in a 1hdt landcruiser turbo diesel, otherwise i would.

now ive done a fair bit of reading on the net and general consensus is 1uz doesnt really cut the mustard as far as an offroad motor goes.

now centrifugal blower or turbos arent going to solve this, as they need rpm to get boost.

a rootes blower - this would work, but im pretty sure it would need intercooling as on long steep tracks in low range, i think it would get too hot. correct me if im wrong.

Are there any other options or do i opt away from the 1uz and buy my dads injected 350 chev lt1?

another question, does anybody know if a hilux transfer case will mate up ok with the a341e? or do i need a landcruiser v8 transfer case?

thanks
Blake

[MOOKIE]

what about the capa style blowers ?

[Robbos_Toyotas]

thats a centrifugal blower, driven off belts (like a belt driven turbo)

[JustenGT8]

Turbos need load not rpm...you'd be surprised how well the right turbo combo will work.

Roots SC is probably a better option though. Conventional air/air or air/water intercooling is easy enough or just use a decent water injection setup.

[love ke70]

if your worried about intake temps, check out the outerlimits forum and have a look at the boys building the laminova coolers.

the blower would be the easier way to make power across the board, but a small turbo would be magic on the 1UZ, no reason you cant get a petrol motor to make boost at similar points to diesels, the airflow might not be as much, having a throttle and all, but the EGT's are higher..

alot of serious crawling is done not much above idle, and most of the torque comes from the gearing, not the motor, theres a reason why modded suzukis on 35s can crawl things at idle and it isnt torque from the motor

[Robbos_Toyotas]

i beg to differ love ke70, the fellows i go 4wding with have turbo diesel cruisers n patrols with factory gears and just suspension lifts and they just crawl at idle out of rutts, whereas in my modded v6 hilux i have to feed it the fat to

[love ke70]

i drive a turbo diesel GQ patrol, i know theyll just idle out of anything, until you put big tyres on it, then it gets harder to drive, needs more clutch and throttle, especially in real crawling situations

whats done to your hilux? its a petrol, its gonna wanna stall at the end of the day you wont fix that unless you go auto, and even then it may still do its best to stall. was watching some vids of the rock bug the other day, pretty sure its auto, sounded it, may have been a very good driver in a manual, but it stalled quite a few times which puzzled me.

no petrol motor will match a diesel at idle, i can drop mine to below 300 RPM since fitting a pusher fuel pump, the alternator light comes on, but it will still pull out of those situations..love to see a petrol do that. even with a charger on it, it will probably still have the stall characteristic, which is why im saying it would really benefit from being geared up to the hills, the 1UZ has revs to play with, so i dont think you would suffer too much in terms of wheel speed per gear. im assuming your going cut gaurds spacers and big tyres?

[wa5]

just put the Chev in it, no substitute for cubic inches (and probably a lot easier to engineer and tune than a blown 1UZ/), it will also allow a Turbo Hydro 350,400 or 700 R4 to be used, and these are all very good Transmissions, There are adaptors available to fit these in most 4x4s.

[the_random_hero]

Twin screw charger. Instantaneous boost and no massive heatloading into the intake charge.

[50RTD]

G'day Blake, agree with you, 1HD is the best diesel ever, smashes those new V8 things.

Anyway, I've had a bit to do with 1uz powered 4bys, particularly hilux's and have a half built 1uz powered 75 series that i am slapping together, and i wouldnt say by any stretch that the 1uz is a poor offroad engine, particluarly in a luxxy that would weigh, what do you recon, 1600kg dripping wet?

What would kill a 1uz powered hilux's climbing ability though, would more likely be gearing than anything, caused by either too big a tyre, too high a diff ratio, etc.

Your truck, being an 81 model, will likely have been a petrol originally, 18r or whatever, which generally had a taller ratio diff (not to mention peg-leg's!). A good start would be to find a set of later model diesel diffs, say 4.3's or 4.5-somethings. Will directly bolt in, makes a massive difference, plus you'd likely get an LSD in the arse end, not that toyotas limo's are any good, but thats a different story/arguement. If you want to get real silly, a set of rockcrawler reduction gears in your transfer case will make it walk up anything...well except for the fact that leaf springs suck arse...(i've got a luxxy too, they dont call em Rollux's for nothing.)

As for the auto box, there are people around making transfer case adaptors for the a341e.
If you decide to go the manual option (as i did, for cutting sick on dirt tracks ) you'll need a bellhousing adaptor, clutch and flywheel from Dellows or Castlemaine Rod Shop etc, however i know dudes mix and match different clutch and flywheel combos with some success, there are even CAD drawings floating around the net to mate 1uz with various boxes.

Oh, and forget about using the G52 box, get an R150 or R151 from a hilux or 4runner. That said, the diesel origin'd R boxes have much lower 1st gears (and probably other gears) than the petrol R boxes, say from a V6 4runner, however you're more likely to find a V6 4runner box for reasonable money, at least thats what ive found.

You wont be able to use a cruiser box as the transfer case output is offset to the drivers side, to suit the offset diffs (unlike the hilux diffs that are centered). They are a physically stronger box too, but seem to fuck up a bit, not the worlds best reputation amongst gearbox people.
If i were to do it again i would use a *coughs* Nissan *coughs* gearbox and adaptor from a GQ or GU. They are mega-tough, bullets will bounce off them, they are not all that dear (because they just dont break), they run a central transfer tailshaft output (perfect for a luxxy) and Dellows and CRS make adaptors for them.

Anyway, as usual, there is much more to the story than i have been crapping on about, send me a PM if you want any info, i have lots of shit i have been copy/pasting over the years.

Cheers

-Dan

EDIT: Best websites around for this kind of shenanigans if you dont already know em Outerlimits4x4.com, Lextreme.com, Pirate4x4.com few other ones, but these my fav's. Cheers

[Robbos_Toyotas]

thanks everyone for your interest/.help
it was originally a diesel, it has 4.88 diffs
. ill look at running 35" x 12.5" tyres most likely.
ill probly look at making it auto - no headaches and cheaper for me as well as having more control on steep climbs not having a clutch.
car doesnt have an lsd currently, but i wouldnt waste my money trying toyota mega slip clutch lsds in it...the one in my new v6 hilux is useless offroad when stuck in a rutt etc...id either get tru tracs or lockers depending on my financial sit.

general consensus seems to be twin screw blower, which is what i thought id need to do...is an m112 too big for a stock 1uz or am i better off going for an m90?

[Hen]

There's a good SC sizing sheet here from Sprintex and linked to by OC originally.

It includes both M90 and M1112, so you can have a play and find what you want.

Hen

[JustenGT8]

I have run an M90 and know others with M112....for response the M90 is a bee's dick ahead and same for low end torque but M112 is the winner for mid to top end as you'd expect. These aren't twin screws though but roots blowers...true 'twinscrews' are Lysholm, far far more efficient (and expensive).

[emp?]

Ive got a mild 350 chev in my landcruiser just running 33's and in low range there anything I havent been able to crawl up even to the point of rolling backwards... the great thing about it is from 800rpm up u can stand on it and it will light up all 4 wheels if you want it to