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Hi

I have doubled checked the calibrations in the motec. The 5 EGT are going into an E888 in the engine bay then in to the CAN bus so the data can be used by both the ADL DASH and the M800. In normal circumstances I too would be worried but the EGT's are correct. The factory turbo charger are really only suited for stock everything. I have data logging to support this claim.

I have been slowly developing this over the last few years when time permitts and this was the first time on the dyno. The intake air temperature from the standard turbo with standard exhaust system goes to 140 degrees on occasions but tends to stay around 115-125 and that is about everywhere.
Guys, this is going into your engine and doesn't make for good torque and horse power. Interestinly EGT's on a standard system complete at 100km's like about 550-630 degrees in the port runners. Simply placing a well designed exhaust system on will drop these by up to 150degrees.
Again then a decent intercooler that doesn't just cools but also flows will again drop another 70odd off. So now EGT's with intercooler and exhaust will be about 200 degrees lower but this trick now is that that the intake air system in front of the turbo is so fucked up, (maybe should have said- doesn't lend itself to the correct volume of air transfer). With the standard air system into the standard turbo it will pull a vacuum in the airbox and feed pipe. This intern gives the front seal behind the turbos compressor turbine a hard time. Another thing is the the standard rubber bend into the turbo is not good for flow. Replace the air box and plumbing with something that works! Clean a few casting flaws from inside the turbo compressor cover and exhaust turbine housing and make a bell mouth for the air flow into the compressor impeller. Place a decent controller on. At this stage with no extra boost the turbos compressor efficiency is exhausted as well as the turbine flow. You can squeeze a few lonely horsepower out now by enlarging the waste gate hole till within 1mm of the size of the flap. But there fuckall left. Your EGT's are now dependant on how much diesel you poke into this thing proportional to the volume of air that enters the cylinders. You will find that there is a major difference between the center two cylinders EGT's due the poor flow characteristics of the intake manifold and the log style exhaust manifold. Porting can help but a flow bench should be used to validate any gains you get. Note: don't touch the outside two cylinders intake manifold runners as they far outflow the center two's.

A decent full sequential LPG injection system will enhance the whole experience.

There are really no turbo's that garret produce off the shelf and import into this country that are designed to make efficient torque and horsepower on a three liter diesel. This point will be hottly debated by everyone no doubt.
The fact of the matter is any of the turbos that have the correct flow maps for the compressor end are matched up to a petrol end size exhaust wheel and turbine housing AR. ratio. Guys we are talking about lots of air flow, more than that of a GT25bb type.

Correct me if I am wrong, but if EGT's are low in every cylinder runner out of the head, the AFR's are not near styro for diesel and there is no black diesel soot coming out of the exhaust pipe then the assumption should be this thing can take more fuel. As soon as you get fluid efficiency and correct flame propagation in the cylinder then things are very happy.

I have done about 25000 klms on the current tune and state of my NAV, Highway towing and city driving and a small amount of beach work. It is what it is.

Regards

Ash

Sorry I for got a bit:
CFD simulation on the factory snorkel shows that the faster you drive the more air it restricts into the snorkel. The hoods a aesthetically pleasing but don't work well aerodynamically outside or inside. On the flow bench the hoods are turbulent and the more air that gets draw through them the more turbulent they become.
The snorkel retaining system doesn't lend itself to good flow nor does the bend into the bottom of the guard.

Again
Kind regards
Ash.


Where did you get the info on the CFD of the snorkle?
 
Solidworks Fluent

Hi

I have a version of SolidWorks with the Fluent fluid simulations module.
I also have data from logging MAP pressures in the air box and snorkel assembly.

A friend who is really good in fluid dynamics, Michael from Airflow Vector also has done quite a bit of development in this area.

Regards

Ash.
 
There is a few things I will pull you up on in your post.
BUT! Only things that I have personally tested on this motor and know for a fact that they arent as you say.
Exhaust system - At best 40-50deg drop, not 150+

Decent Intercooler however can offer more than a 70deg drop as you stated.
Generally without further tuning, what you drop Intake temp by, exhaust will drop by an equal amount.

Opening up the wastegate wont make any appreciable difference to power at all. Only the ability of the turbo to run lower boost.

The GT25XX have been tested and is used on a large scale in many countries on this motor with fantastic results. Some searching and you will find many kits to upgrade the standard unit to this good little ball bearing unit.

When you think of how much extra air you are squeezing into this thing and also Air Fuel ratio.
The more air you put in, the leaner it will be.
Add fuel and it will get richer.
So if you have performed all these mods, and running still 17:1 up top. That is alot of extra fuel.
The standard ratio for these motors is 22-24:1 under load. 18-19:1 down low. That gives 650-700deg pre turbo exhaust gas temps.

So your problem I see is this.
1) The o2 sensor thats being used is possibly wrong, as you said there is no smoke? Because anything less than 18:1 on this motor is smokey. 14:1 and the smoke would be thick enough to rival a Yanky Sled pull tractor.
2) The temp sensors are not scaled correctly.
3) LPG injection is just wrong by design on a diesel motor for reasons that are to numerous to go into, and could be the reason the AFR is so rich.
 
In normal circumstances. Everyone needs to look outside the square,

Hi

Obviously in normal circumstances this might be the case but if you only have a hammer in your toolbox then everything will look like nails.

Just because someone has done something different doesn't mean it won't work. Obviously you guys aren't ready to look outside the square.

by!

Regards

Ash
 
I wonder if by 'looking outside the square' you mean doubting a questionable dyno graph, and giving good factual information on some of the oddities in the data you provided?

The reason I take the time to question these things is so other users/readers without the knowledge and experience in the field I have can get some information on all sides of the story.

The information you provide on intercooling and exhausts etc... Is great and what people need to hear.
The fact is though, im not here to bag out your car. Im giving you evidence and theories on the graphs you have provided from experience.
If you want to keep thinking its loss of traction in your graphs, so be it...
If you think the egt's are that low pre turbo, so be it...
 
Finally got round to getting my ZD30 dynoed. Reckon i can probably put some more fuel in down low and see if it boosts up a bit earlier but about what i was expecting.
 

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Diesel tuner what are your thoughts on water meth, I'm running a 6 GPH 45/55 mix twin nozzle it provides huge power.
I'm running the billet stage 3 wheel from forefront with no changed to the exhaust housing or waste gate diameter.
My chip is maxed out with a 2.5 straight pipe and xr6 front mount.
All running 20 psi at 2100 ish
Very light film of smoke at full noise with pre turbo temps at 620 to 650c
Thoughts?
 

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