Turbo upgrade

Hi Martyn, thank you, I definitely could be interested if I am not too late. But I am dumb on turbos - what are the benefits/handicaps of wastegate turbos? Will the new turbos be bolt-on replacements or will plumbing be needed? Thanks for making the offer, Cheers Paul

I too could be interested. Just need a little more info. Are they the same stud pattern, what size, model, water cooled, A/R ratio etc?
Peter

Sounds good mort would be interested, same as everyone else, alterations to existing inlet manifold and other plumbing? Thanks for the thread.

Hi All, The turbo will be direct bolt on same oil connections same exhaust. I have a friend who is a head mechanic for a racing team who is helping with sizing and testing so we might have to trial 2,3,4,combinations till we get one that is best not all boost at bottom and none at top or none at bottom and all at top but a reasonable spread and a max boost of around 16.
The reason for changing is I mounted an intercooler up front which meant 1.2mt piping to intercooler and same return however before I was getting max boost of 14 now max boost of 10 so the benifit of cooler denser air is lost by too much drop in boost and going to wastegate means you dont over boost as it can be set and in this case set at 18.
Its not too late as we need to install test in operation and make changes as required etc and when we are happy get dyno then ready to place order. I am doing this for myself and it is no extra effort to order 1 or ten and if lucky it may bring the price down so why not pass the benefit on.
when I am ready to order which could be a few weeks I will let every one know so there is still time to confirm your orders

Mort

374 has always pulled up around 17lb boost at full throttle, I have never done anything to it and I doubt the RAAF ever touched it either. Engine is totally stock, just the drivetrain that's been changed.
Being a longtime Landcruiser owner I was horrified at the boost and EGT levels when I first fitted the gauges but was reassured by a couple of Perkins engine specialists that my figures were fine, in the normal range and the engine could handle it.

!6psi is not that much for a factory turbo the 6bt in the dodge application is about 20psi, after a lot of research 35psi seems to be a safe limit for a daily driver with no internal mods, obviously with a different turbo. One would have to think the Perkins could take a bit. If it couldn't handle 17psi all day there would be a lot of dead OKA's out there. I know when i was still running the Perkins the foot was on the firewall most of the time.
When I upgraded the turbo in my Cruiser I spoke to a guy (who I ended up buying a turbo from) who was very quick to inform me that heat was a higher risk rather than boost and more boost in a well matched turbo means lower EGT's. With my new turbo with the same load my EGT's are about 100deg c lower than before with about double the boost so for example I went from about 6psi towing to about 13psi this combined with about 400rpm quicker spool up and 17psi max instead of 12psi what a weapon.

Rob

Hi Mort, I am interested in one too.

Hi, has there been any update on these

Hi Darren and everyone else I am onto the third prototype all going well just want to get the best I can.
If I was only doing for myself maybe I would stick with what I have so far but as so many have shown interest I want to get as best as possible. The issues are the 135TI turbo has a different size mounting to manifold,exhaust out to dump pipe and oil in and oil out so now we need to change the cartridge and turbine to suite the 110 existing fittings this will allow for a straight bolt on turbo with no adapters etc so now I wait till its ready then fit and test.
Martyn

OK just an update I have fitted the third turbo which took some time as I am aiming for not only performance but a straight bolt on I thought it would be easy with the huge number of Turbos out there but that is not the case. the limitations were the exhaust in and out without the need for adapters or new dump pipe and that part was relatively easy but the hardest part was to fit without modifying the gear linkage so we had to design the wastegate and exhaust out housing send the design overseas to get it cast, machined and assembled so end result is its the only one in the world now its fine tuning which started today after all that effort I am not completely happy so its trying different turbine and compressor wheels till I get what makes me happy.At least it will be much better than what is on there as it will de designed for the OKA and not a tractor or excavator.
Have patience
Martyn

mort wrote: The issues are the 135TI turbo has a different size mounting to manifold,exhaust out to dump pipe and oil in and oil

Martyn,
I have been looking at differences between 135TI and the 110 in the hope of an upgrade and came across this problem. Got too hard for me.

Are you considering intercooling?
Based on my experience with the 110 I think it would make a huge difference but the changes to the input volume and pressure need to be taken into account with the turbo specs and the injector pump settings.

You have put a lot of effort into developing a working solution. I would like to join the queue to purchase a unit when you have it sorted.

Rick

Martyn,
Add me to your list as well.


Regards,
Geoff

Well I have some update re turbo with the last one the engineers asked me to do some tests for them which seemed easy enough all I had to do was drive and record the boost pressure,revs and what gear I was in and whether flat,hill,city or country also fuel usage well watching the road and gauges changing gear and writing down wasn't that easy I think surfing the net on my mobile phone is easier except its a big fine.
Anyway all sent to the engineers who got specs for the engine and original turbo and set up a test bench,6 weeks later they have all they need to design and build a whole new turbo production starts this week with completion due by the 20th then testing and ready for shipping by 27th so I should get it by early April.
On their report back to me they did comment that the problem with the original was the compression ratio as it was very low at 1.73
The reason for the road test was to see what is the rev range in normal use and design a turbo to suit

Its taken a bit of effort and cost but I will get there in the end.

Martyn

Still very interested in this turbo up grade, let us know when you are going to order. Our mobile 0447 445622 not that up to speed with chatting to other OKA owners on this site one day will sit down and work it out. For now could you please call us.
regards OKA 398

Hi Allabout,
I have been reading your post on turbos.. My 187 has a boost gauge, and at full noise gets to 10psi. The EGT gauge is still waiting for me to repair it. It is also fitted with an intercooler, and the NP205 transfer case, and it can clip along at 110 kilos [GPS] effortlessly all day. My work vehicle [430] with a good engine and new turbo struggles to maintain 100 kilos, and would only do 110 kilos down a mine shaft with a tailwind..
Cheers,
Nobby.

Nobby
Are you getting full Throttle travel in 430?
the two places to check are :
1/. At the pedal, over time the pedal bends and will bottom out on the floor, and an easy fix as it will bend back by hand
2/. Another common place is where the throttle cable attaches to the pump, the outer case can often slide, there is a locating ring on the cable to stop it from moving and is often not clamped in it's home position.

Nobby, I have heard it said that the Rockwell transfer case fitted to the LT's sucks up a lot of power, and that might explain the difference in performance between your XT and the work LT.

The difference in speed can be several things.

Tyres Size
Heat
Getting full throttle
Terrain
Condition of engine etc.

My current OKA is good for running all day at 100 - 110 kph.

Other OKA`s I have owned where flat out doing 80 or 90.

Half a turn on the fuel adjustment screw on the pump will give more fuel, more boost, more smoke, lots more power and higher EGT.
What maximum EGT do people think reasonable?
#196 will cruise at 100kph with a max EGT under 500C and boost around 12+psi.
I have run it with more fuel and max ECG 550C and boost up to 17psi. It produces lots more power at that.

Cheers,
Peter

Below 500C shouldn't cause to many problems Peter I seem to recall that 612C was injector tip melt temp on a Mack engine I once owned and I would say that injector tip material would be much the same in all old type mechanical engines like the Perkins.
Fuel temperature also plays a big part so keep that below 60c, I would say its unlikely our Oka / Perkins would have a problem of that nature but a fuel cooler is quite easy to make and fit if required.

Cheers Dave