Offroad-Express

Well last tune snapped the crank and orange is sitting idle.
Time to build it properly.
Balanced rotating assembly.
Shotpeened polished and nitrided.
Stage 2 cam
Valve springs?
Ported head and precups
Injector drop
Amputated qd32 manifold
Big gate and same old 3126 cat turbo

bolting gussets to the block this time? or maybe an after market full length CNC bearing cradle to help stop the flex

or billet crank shaft maybe

Haha did look at a cradle setup,
There is bosses in the block down one side of the mains,
Be interested to see the dakar 42 engine with its pants off,
Got a feeling harmonics killed this one,
Will sneak the piston/rods onto her flash digital scales haha,
After a couple bits though,
Precups - new (steinz?)
Qd32 intake mani (long runner 2 piece job)
Also thoughts on getting cnc waterpump impellers done .

what was the cause of the crank failure?

any idea of what power/torque output it has?
what injection system is it running?

just wondering if its sheer big power, oil issue or vibration issue.
i havn't been on the patrol forums for a bit but there was billet cranks being made. however theres a fair bit of talk on vibration issues causing crank failure. part of that is flywheel weight but also front pulley.

Never dyno'd it.
Kept up with a trundle truck full of tools spares etc with slipping clutch in 3rd 4th,
That was 200kw.
My pumps a 12mm 1hd hybrid.
Turbo nozzles more crack pressure shimmed in.
Modded intake , cooler, airbox 4" to turbo inlet,
Standard twinscroll cat 3126 turbo think its an s200 under license.
Home tune to afr and egt.
14.6 afr bottom on accel,
550 max pre turbo egts,
Boost control off max fuel and foot,
Topped out at 43 psi in top gear wound out,
Easily hoiked front left.
Snapped clean through no.6 rod journal whilst idling home after work 4.30am one morning

slidenyo wrote:Never dyno'd it.
......... with slipping clutch in 3rd 4th,

fit a new clutch?
check the clutch weight. i recall this being an issue when dealing with flywheel weights.

slidenyo wrote:Never dyno'd it.
Kept up with a trundle truck full of tools spares etc with slipping clutch in 3rd 4th,
That was 200kw.
My pumps a 12mm 1hd hybrid.
Turbo nozzles more crack pressure shimmed in.
Modded intake , cooler, airbox 4" to turbo inlet,
Standard twinscroll cat 3126 turbo think its an s200 under license.
Home tune to afr and egt.
14.6 afr bottom on accel,
550 max pre turbo egts,
Boost control off max fuel and foot,
Topped out at 43 psi in top gear wound out,
Easily hoiked front left.
Snapped clean through no.6 rod journal whilst idling home after work 4.30am one morning

Awesome! Good post.

Any videos of it running?

A couple on fb.
Nothing spectacular haha should have got it to the drags,
New build have a viper clutch to try and will ditch the clutch booster.
Will send front dampener to pressure plate to balancer.

that's how my engine was balanced all spinning gear balanced up

Snapped crank, sounds like a dual mass flywheel would help here.

well atleast if ya went billet crank you could have the bearing journals bored out on the block and run larger journals over size bearings to give the crank more meat/strength where its needed.

Yeah fair call ,
Dont have the cash for a crank as well unfortunately,
Will just have to leave the tune about where it is but drop the compression a tad and fit a gate to regulate boost.
When i get some more bush cleared and some regular income off my block i'll look at it i reckon. But then i did consider an fd46t swap instead of rebuild.

There's a lot of instances of crank failure now in Aust, all determined
to be harmonic issues when you've got big power. But some of the failures
they have had have occurred during normal driving. Billet cranks seem to be
the go but not cheap. I've just put a new clutch in so I changed the flywheel
to an aluminium one which is a few kg lighter than the factory one, that and renewing
the front balancer.

Now that's another thing to look at.
Alloy flywheel what'd it set you back?
Have had billet 3.8 ones made at about $550.
Not sure I'd want to carve the meat out of a standard one but could be worth looking at.

Starting to have a play before i buy a new set to port and fit,
Will get it how i want it then make some tin profiles to get them the same.
Mainly a blend job an slight enlargening of the mouth.
Also a small radius on th tip point in the cup to stop the heat cracking it so much.

Bit more into it.
Might be time to get a virgin set and lay into them.
Precomp chamber volume will be increased and air/fuel exit resistance decreased.
Also going to set the injectors 60 thou deeper by taking down the heat shields.

Few more bits on the way.
S200g Borg turbo from turbocare.
Twin scroll .64 ar gated housing 20 pound actuator.
Billet lightweight flywheel to suit viper clutch. (Quite reasonable price too $650+gst)

slidenyo wrote:Now that's another thing to look at.
Alloy flywheel what'd it set you back?
Have had billet 3.8 ones made at about $550.
Not sure I'd want to carve the meat out of a standard one but could be worth looking at.

Sorry slidenyo...only just noticed this.
Wasn't cheap, $1000 Aussie dollars but machined up by a guy on the Patrol forum and Faceache specifically for TD42's.
Then Customs put their rape charge on as well.

No worries decided on billet as I'm getting it balanced anyway.
And happy to support the kiwis building them. Will get a cad file out of it too.
So if anyone else is keen they can grab one.

More pieces to the puzzle.
Turbo and precomps turned up.
Picking up flywheel Monday.
Cheers to Jarrad at turbocare for the loader turbo

Even the young Sid's happy bout dads plans

Awesome stuff Jase, love the tech details and research in your work.

We shall see if all the worship to numbers pays off think ill chuck it on the engine dyno at kopu engineering once its run in.
Cheers josh wheres the rano now? Still in storage?

And more stuff

Light

slidenyo wrote:Cheers josh wheres the rano now? Still in storage?

Can't shake the stupid thing
Low priority at the moment, but I have this IFS front cut sitting in the corner, will eventually use it as a testbed for the coilover/long travel project...

Get the diffhead bang in the centre using an irs half shafts? Then a second transfer case to get drive out the side?
Or just narrow the ifs diff?

slidenyo wrote:Get to the diffhead bang in the centre using an irs half shafts? Then a second transfer case to get drive out the side?
Or just narrow the ifs diff?

Extended a-arms, increase total track width by about 4-6" for mega stability Then a full float Atlas rear end/spacers to match the rear.

Defo IRS shafts, likely the 300ZX turbo 30mm axles with Safari outer CVs. Seems like the inner spline count might be the same, and they are a good length