Leprechaun
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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?