Outer Limits 4x4 Board

Hi Guys,

I have a 99 model GU wagon (td42 motor) with 156,000kms that I had a DTS turbo fitted to in May. I run 33x12.5x15 Cooper ST's. I also own a Jayco off-road camper trailer that weighs in at just over 1 tonne. We recently spent 2 weeks in and around Exmouth and Coral Bay towing the Jayco to and from Perth. My question relates to towing performance or what appears to be a lack of it on our return trip.

The pre turbo dyno run showed 84kw & 264 nm of torque.

After the turbo was fitted it increased to 97kw and 309nm torque. Modest boost of about 8-9 psi max was set by the installer.

1. Do these figures sound about right for a DTS system, I'm chasing power and reliability?

The turbo is certainly noticeable when not towing. At 100kmh it pulls around 2200 rpm with an EGT of about 260 degrees celcius. (EGT sensor post turbo in dump pipe). When you put the foot down in 5th at 100 the speed picks up quickly. Fuel economy around town not towing is 15l per 100km (steel bullbar and rear bar with swing away spare and full length ally r/rack).

On the way up to Exmouth towing the Jayco at between 90-100kmhr consumption increased to just over 17l per 100kms using 5th gear to tow as it was doing it easy. Between 100kmh and 110kmh consumption increased to about 21l per 100km. Overtaking was not all that hard.

On the way back to Perth things went pear shaped. We had fairly strong winds and hills and I was battling to keep it at 100kmhr in 4th gear and EGT's were hovering anywhere between 490 to 515 degrees briefly peaking at 530 and I was struggling to overtake the slow pokes on the road. The engine just seemed to lack power. 5th gear was not an option and fuel economy went out the window to just under 24l per 100km. At one stage speed dropped to 80kmhr with the accelerator pinned to the floor, she just did not have any more to give.

Closer to Perth things improved after I got a full tank of bio diesel in Geraldton.

I think my problem was either crap fuel at Exmouth or I let the tank run down too low and sucked some crap through the fuel filter because after I ran most of the bio diesel things improved but not quite the same as on the trip up. Does this sound right? If it is what do I need to do to get things running right again? (eg replace fuel filter and run some injector cleaner)

I have taken it for a spin without the Jayco on the back since we got back and all seems normal.

For those of you with a similar set up towing a 1 tonne trailer I have the following questions:

1. What sort of top speeds can you maintain?
2. How hard do you find overtaking?
3. What is your overall fuel economy like?
4. How do my EGT's stack up with yours?

Sorry for the long post. So many issues, so many questions!!!

Cheers
Mark

G'day Mark,

My ute was set up with a safari turbo system intercooler when I brought it. Fuel economy loaded for easter long weekend including 2 MX bikes on a trip to Esprance returned around 15L/100km @ 100/105km/h. Once we hit the head winds down near Ravie it drank a little more. Anthing over the 100km/h and the drinking issue gets bigger.

I think your pyros look ok considering the fuel burn (24L/100). 530 max foot planted in forth skull dragging a ton behind you isn't to bad in my opinion.

Your pre and post turbo figuers are intresting, ruff estimate 20% would that be right? I would of thought you would see slightly more. Does it have a 3" exhaust etc?

The head winds up there are killer and what you have explained concerning fuel burn and needing to us forth sounds right. I went up there five times last year and have always ran into that on the way home.... and thats in a falcon with nothing behing it.

I know you are more loaded but just some in put.

Daniels (booster)

Maybe Andy from Diesel Tec can chim in?

GQGasPig wrote:Hi Guys,

I have a 99 model GU wagon (td42 motor) with 156,000kms that I had a DTS turbo fitted to in May. I run 33x12.5x15 Cooper ST's. I also own a Jayco off-road camper trailer that weighs in at just over 1 tonne. We recently spent 2 weeks in and around Exmouth and Coral Bay towing the Jayco to and from Perth. My question relates to towing performance or what appears to be a lack of it on our return trip.

The pre turbo dyno run showed 84kw & 264 nm of torque.

After the turbo was fitted it increased to 97kw and 309nm torque. Modest boost of about 8-9 psi max was set by the installer.

1. Do these figures sound about right for a DTS system, I'm chasing power and reliability?

The turbo is certainly noticeable when not towing. At 100kmh it pulls around 2200 rpm with an EGT of about 260 degrees celcius. (EGT sensor post turbo in dump pipe). When you put the foot down in 5th at 100 the speed picks up quickly. Fuel economy around town not towing is 15l per 100km (steel bullbar and rear bar with swing away spare and full length ally r/rack).

On the way up to Exmouth towing the Jayco at between 90-100kmhr consumption increased to just over 17l per 100kms using 5th gear to tow as it was doing it easy. Between 100kmh and 110kmh consumption increased to about 21l per 100km. Overtaking was not all that hard.

On the way back to Perth things went pear shaped. We had fairly strong winds and hills and I was battling to keep it at 100kmhr in 4th gear and EGT's were hovering anywhere between 490 to 515 degrees briefly peaking at 530 and I was struggling to overtake the slow pokes on the road. The engine just seemed to lack power. 5th gear was not an option and fuel economy went out the window to just under 24l per 100km. At one stage speed dropped to 80kmhr with the accelerator pinned to the floor, she just did not have any more to give.

Closer to Perth things improved after I got a full tank of bio diesel in Geraldton.

I think my problem was either crap fuel at Exmouth or I let the tank run down too low and sucked some crap through the fuel filter because after I ran most of the bio diesel things improved but not quite the same as on the trip up. Does this sound right? If it is what do I need to do to get things running right again? (eg replace fuel filter and run some injector cleaner)

I have taken it for a spin without the Jayco on the back since we got back and all seems normal.

For those of you with a similar set up towing a 1 tonne trailer I have the following questions:

1. What sort of top speeds can you maintain?
2. How hard do you find overtaking?
3. What is your overall fuel economy like?
4. How do my EGT's stack up with yours?

Sorry for the long post. So many issues, so many questions!!!

Cheers
Mark

Where did you have it fitted and have you taken it back to have it checked.

Headwinds will knock the crap out of most things.

All the power figures and pyro's seem good to me.

Matt

Think of egt's as engine load. It is telling you how hard it is working. Do you have graphs before and after, do they show boost pressure against road speed or revs?

This will help to find the right driving range. Towing in 5th gear doesn't always give economy.....try riding a bike in high gear all the time, how much energy do you require.




Andy

if head winds are such an impact (and i agree they are) perhaps on the "up" trip you most probablly had strong tail winds which could have a considerable impact on your up vs back figures/feeling through the seat... just a though...

I just did a trip to the gulf and I found that the different fuels seem to make a difference, I got a couple of bad tanks full and mine did the same as you have explained no power and overheating as well, I could only put it down to the fuel as the car came good after a refuel

Another thing to consider is air quality... did u suck much dust into the air filter? Also tyre pressure was it different? although small things these can make a bit of difference to the final fuel figure. Has an air hose from the turbo come loose?

I think you are on the money when you say the fuel might be an issue. I cleaned out the tiny brass filter in my fuel pump and it made a massive difference to the rev range for a while. before it would not rev past about 3500 the after I cleaned it it would rev all the way to redline.

Hi Guys,

Thanks for the responses.

To answer your queries:

It has a 3inch dump pipe with 2.5inch exhaust

I have scanned a copy of the dyno graphs (before & after) which show revs on the horizontal axis, KW on the left hand side vetical axis and torque on the right hand vertical axis. Have no idea how to get it to display here. Can I e-mail it to someone who can do it for me (volunteers PM me)

Air quality is good as I have a snorkle and checked the air cleaner and it appears to be clean.

Tyre pressures up and back were the same 40-42 PSI.

I have not touched base with the installer yet as I thought I would get clued up a bit here as this is my first diesel truck.

I have not checked air hoses to the turbo but will do so. Also I have read about cleaning the brass filter on top of the fuel pump. I'm willing to do this but need to know if this will mean that I will get air in the fuel lines which will require me to bleed the injectors?

Also is it easy to push aside the metal pipe that is bolted to the fuel pump where the filter is located once the bolt comes out? Do I need to be aware of any small parts that may fly out once this bolt is undone?

Keep the info coming and thanks for your help.

Cheers
Mark