Outer Limits 4x4 Board

Just would like to no what the 3lt skyline motor is like on fuel and how dose it perform on and off road and will it tow a campervan ok.
Any info on the 1990 patrol with the 3lt will b appreciated.
thanks Lewy

Me and a mate both have the RB30, there fine on and off road with no trailer on the back, I find with the 35's bolted on crawling up Huuuugggee hills is hard as they make no power at 1500rpm, but for all other 4 wheeling there great.

I should mention it will climb a mud hill like nothing if you have revs up around 2000-3000rpm but if you need to crawl over rock for example you will be using the clutch alot. If you run 31 inch tyres no probs it gets over anything becuase you can use the revs.

Also the gearbox is the close ratio out of the 300zx so towing on road is great as there is hardly and revs lost between shifts, but probably shouldnt tow stupid amounts of weight as the gearbox wont like it...unless you use 4th.

They will tow a 1.6 ton half cabin boat at the speed limit so I guess your camper trailer should be fine....untill you hit the hills.

Good thing is the motors are cheap as anything to replace and rebuild, and you can fit the VL turbo gear on with straight gas so you end up making lots ok poke for little money and running on GAS so its cheap.

just be warned if you put a turbo you may find the car is under boost at highway speed even without load as the wind drag on the car is enough to make it boost so your fuel usage can suffer if you turbo it.

If you fitted a reasonable 2 1/4 inch exhaust with cheap extractors using small primary tubes you would get a small gain, just enough to make it move along a bit more happiy.

With the misses driving 90 litres of gas gets her over 400kays full city cycle and thats with our car weighing in at 2.2 ton.

Extractors and two and a quarter inch exhaust with free flowing muffler makes a fair difference. Removing the restrictor from below carby helps heaps too ....but cut it off flushwith bottom of spacer....complete removal leads to poor slow running and idling. Fitting a snorkel makes a gain as well....but reverse snorkel head on cold and frosty conditions as the carby can ice up. Also these motors are preset fairly lean at factory, so a session on the dyno is worth it. The vacuum advance unit can split inside and quit, especially if the truck has been left standing for a long period ...ie...months. Towing is more economical and easier on powertrain if fifth gear is not used on anything bigger than an empty box trailer, there is only about 250 revs different between 4th and 5th anyway...but the difference is noticeable and your gearbox will thank you for it.
I have done all of the above to mine and keep it in top tune...and fuel consumption is around 12-14 litres per 100 k at road speeds....mostly with air on too.
these are an awesomely strong motor and will last as well as any other if well treated and looked after. You will get a feel for best performance from it over time and should be able to go well with it.
Hope this is of some help.


Cheers Keith

fuel injection off a vl makes big differece im getting about 140hp at the wheels. any one know what a std carby has

a non efi rb30
is between the 90 and 100 hp (kw)

stage 2 cam also gets the rb30's up and going
we had 1 installed about 12 monthes ago by a shop.it had no go untill we found it was 6 degrees out.but now it is runnig great u can get some hi revs out of him up a steep hills.we also are carrying 35's plenty of go in the bush a bit slugish on the high way it still ova takes the stock turbo 4.2s until u hit a decent hill.go back a gear and of she goes

i got a mate that just bought a gq with a rb30 in it staright gas turbo and it makes 200kw at all four blows the doors off ss commondoors just an idea as buying go fast bits for rb 30s are cheap

I second (third?) the EFI idea. Buy a complete R31 sedan in good running condition (crappy or smashed bodywork maybe), for probably $500-1000 and swap in all the EFI gear, and ignition obviously.

I'm an utter offroad novice but I am 100% sure if you're running petrol, then EFI is the way to go.

we priced up a full turbo kit from jpc turbo's dats efi and the lot for 4'000 i think it is a fair price.its garenteed to b double the horsepower

is that installed?

no its not as yet we have 2 waite a monthe or 2
they do 3-4 of them a monthe for comptrucks and they sed 2 see how they perform we can take 1 for a spin.ive seen there commodore go and it lifts both front wheels of the ground now.they no wot there doin
:D

You can find a whole heap of information on modifying RB30's here www.calaisturbo.com.au