Outer Limits 4x4 Board

Hello all,

I’ve just turboed my 99 HZJ105 Auto with a DENCO kit and replaced the stock exhaust system.

I must say I’m quite disappointed with the results. The kit does not seem to provide any boost at all till about 1,600 RPM. From that point on wards the turbo kicks in and I get a full 10 PSI boost at about 3,500 RPM. The kit has made a significant difference in Highway driving but there is no benefit at all in low RPM’s.

I also have a ‘06 intercooled turbo(factory) Montero. Here the turbo provides boost from idle and the Montero can run circles around the turboed 1HZ.

Does anyone have any experiences / comparisons they would like to share?

Any comments?? anyone?

did you up the fuel too?

The 1600rpm figure for the boost to start sounds quite typical, however on my 1HD-T with Beaudesert 3"mandrel bent exhaust and basic boost controller, I get full boost at around the 2000rpm mark. I rarely have to extend the revs past 3000.

cheers

Stuart McMurtrie
Brisbane

Of course the Mitsu will get boost right from idle. Those engines depend a lot on the turbo. Don't expect it to last as long as your 1HZ. That engine is stressed out all the time.

Your 1HZ getting boost at 1600 is OK. If you want it to boost sooner, you could try tweaking the wastegate (if it got one) or adding a boost controller, but then you'll be stressing it sooner and it will not last as long as with the "normal" settings. Also, have you increased your fuel ?

If you're after power at low RPM you should consider more reduction (R&P and/or transfer gears)

Hello All,

Thanks for the replys. Wish you all a very happy and peaceful new year!

Yes the fuel has been adjusted. The fuel screw has been turned by 3/4 of a turn so that EGT is at about 450 C at full throttle. There is now a very slight smoke on full throttle take off.

Did another test run today with one of my mates 99 4m40 2.8L intercooled turbo stock.

On a straight line I can't even get close to him till about 90-100 KM/H. From that point onward the 1HZ catches up without any problems.

How would a boost controller help in getting boost at low RPM?

Also I noticed the following:

If I keep the engine in Neutral press the accelerator the turbo does not seem to make much boost. At 4000 RPM only 5 PSI

By on Drive with the vehicle moving at 4000 RPM I get 9.5 - 10 PSI Boost.

Isn't this VERY odd???

malinda_um wrote:Hello All,

Thanks for the replys. Wish you all a very happy and peaceful new year!

Yes the fuel has been adjusted. The fuel screw has been turned by 3/4 of a turn so that EGT is at about 450 C at full throttle. There is now a very slight smoke on full throttle take off.

Did another test run today with one of my mates 99 4m40 2.8L intercooled turbo stock.

On a straight line I can't even get close to him till about 90-100 KM/H. From that point onward the 1HZ catches up without any problems.

How would a boost controller help in getting boost at low RPM?

A boost controller is basically a device that creates a "leak" on the wastegate and "fools" it into "thinking" that it has not reached the set psi where it should open up and stop boosting, thus increasing the boost levels.

http://en.wikipedia.org/wiki/Boost_controller

Can't your wastegate be adjusted ? I'm no turbo expert, but I think if you need more boost sooner, you'll have to change your turbo's hot side ...

hey mate i had a denco kit on my 1hz with a dts top mount ic and a compensator on the pump with a elec inline pump and wow what a difference. made 13lbs of boost at 2000 with 152rwhp and 1050 lbs of torque so i would have 2 say take it 2 somone who knows how 2 tune it properly.

malinda_um wrote:Also I noticed the following:

If I keep the engine in Neutral press the accelerator the turbo does not seem to make much boost. At 4000 RPM only 5 PSI

By on Drive with the vehicle moving at 4000 RPM I get 9.5 - 10 PSI Boost.

Isn't this VERY odd???

thats always the case when the engine is not under any load and free reving

hulsty wrote:

malinda_um wrote:Also I noticed the following:

If I keep the engine in Neutral press the accelerator the turbo does not seem to make much boost. At 4000 RPM only 5 PSI

By on Drive with the vehicle moving at 4000 RPM I get 9.5 - 10 PSI Boost.

Isn't this VERY odd???

thats always the case when the engine is not under any load and free reving

also

dont free rev your engine to 4000rpm, it makes the toyota gods cry

tuff 75 wrote:hey mate i had a denco kit on my 1hz with a dts top mount ic and a compensator on the pump with a elec inline pump and wow what a difference. made 13lbs of boost at 2000 with 152rwhp and 1050 lbs of torque so i would have 2 say take it 2 somone who knows how 2 tune it properly.

SPOT ON...

send it to a proper tuning mob with a dyuno who specialise in diesels.

it will be a TOTALLY different animal. might cost from $150 to $700

malinda_um wrote:Also I noticed the following:

If I keep the engine in Neutral press the accelerator the turbo does not seem to make much boost. At 4000 RPM only 5 PSI

By on Drive with the vehicle moving at 4000 RPM I get 9.5 - 10 PSI Boost.

Isn't this VERY odd???

No, it wont boost if it has no load

Thank you for the replys guys!

unfortunately I don't have access to a Dyno (I live in Sri Lanka).

4wdsystems suggest that my 1HZ is under fulled. They recommend increasing fuel further 1/4 turn. If all else fails to play with the wastegate.

Could someone tell me if there is any harm in running a lean mixture? Other than the obvious performance deficit?

no harm can be done at all. Just gotta flog hell outa ya car 2 make it go anywhere

malinda_um wrote:Thank you for the replys guys!

unfortunately I don't have access to a Dyno (I live in Sri Lanka).

4wdsystems suggest that my 1HZ is under fulled. They recommend increasing fuel further 1/4 turn. If all else fails to play with the wastegate.

Could someone tell me if there is any harm in running a lean mixture? Other than the obvious performance deficit?

a lean mixture in a diesel can do no harm to the engine whatso-ever. Its completely opposite to a petrol engine, where a lean mixture will cause much higher combustion temperatures and can lead to catastrophic engine failure.

The problem in a diesel is running too much fuel. But aslkong as you keep an eye on your exhaust gas temperatures you will be fine.

Thanks for all the replies and advice guys.

Increased the fuel as 4wdsystems said. There is alot of power at about 3,000 RPM but will very little at 2,000 (3 psi).

Do you guys have any idea how I can get the turbo is boost at about 1,500 RPM?

Once again.. thank you for all the help.

sounds like not enough fuel. my pump is screwed right in and it goes very good, also has a big front mount cooler and a 3in exhaust though. i've had no problems and motor(1hz) has done about 550,000 kms and it's been turboed from 340,000kms. it get's a hiding too. i'm not kind to it at all.

oh yeah, it's a mtq(dynamic turbo) turbo it starts boosting from about 1200rpm and i have 10psi from about 1600rpm and 16psi from 2000-3500rpm. i have a tee in the wastegate acuator line that bleeds some air back into my air box.

earier boost will require more fuel or a turbo change. boost tees or controllers just make more boost which need higher revs. maybe your r is a dud...... there are heaps out there that just arent as good as others and some which are heaps better. mitsu common rail diesels are the shit.... best feeling turbo diesels i have driven, they kee up with the petrols.

I don't think I can add anymore fuel. With the current setting the car leaves quite a large trail of black smoke on take off. Also if I go full throttle, EGT goes to 500+ at about 100 Kmp/h. So fuel cannot be the problem. The only way I could add more fuel is with a boost compensator and an intercooler. The problem is that the turbo is not doing anything much at all below 2200-2500 RPM. Since most of my weekday driving is in the city, the turbo really is not doing anything at all. I just running an over fueled 1HZ.

Will see what Denco and 4wdsystems have to say about it.

I agree with you about the mitsus. My 3.2L 4M41 boosts from idle and is very very quick. The thing that pisses me off is that even a 99' 2.8L 4m40 (indirect injection) seems to have so much more power at low revs.

Will keep you guys updated...

As always... any comments or suggestions are most welcome.

the turbo must be waaaaayy to big for a 1hz or it's rooted

What do you mean by 'rooted'??

mule75 wrote:the turbo must be waaaaayy to big for a 1hz or it's rooted

ya gonna have to speak in english for the non downunder crowd

for malinda_um, rooted = cactus = rebuild time

Thanks Udm

rebuild time for engine or turbo?

The engine has only done 115,000 KM. 1HZ is in perfect condition. I'm the 1st owner. All services done on time. Mobil 1 fully synthetic used from day one.

Turbo is 2 weeks old! Got it from 4wdsystems. I guess the turbo could be faulty.

malinda_um wrote:rebuild time for engine or turbo?

mule75 was referring to the turbo been rooted... but probably not, as you have just mentioned that it is new.

something doesn't sound right. maybe faulty??!! is it the correct turbo for a 1hz????????????????????????

My 75 1hz starts boost at 1200rpm and goes all the way to 4000 rpm.

I fitted a turbo glide unit . Garret t28 and 9 psi. Best kit ever