4jg1t "franken-engine"

[handymanny01]

Ummm, you sure your egt isn't in Fahrenheit? That would be 650c, which sounds bout right,,, 1200 degrees c is almost twice the melting point of your piston alloy,,, forged or cast, What did you do to the td04 to "high flow" it? What's the compressor wheel size? I've seen an upgrade td04 available form kunigawa , but didn't see specs on the wheel sizes... all info is good info!

[geeves]

Steel often melts at around 1370 degrees C
Not much of a safety margin
Melting Points
Metals Fahrenheit (f) Celsius (c)
Iron, Wrought 2700-2900 1482-1593
Iron, Cast 2060-2200 1127-1204
Iron, Ductile 2100 1149
What sort of cast iron is used for the manifold? Might explain that small drip

[isuzurob]

Its cooler on top of the piston with water and oil sqirters, manifold is just raw heat, and yes its 1200 degrees Celsius with a vdo gauge not cheap rubbish, at 600 it's slow as anything as I said fuel=power and that's what I aim for, from memory turbine wheel is 11 blade and compressor is 12/6 blade and 63mm/48mm, that's off the top of my head, everyone says 650 is safe when talking to tuners but no one really knows what things can handle, as I said 2 years of absolute abuse at 1200 degrees c and punched the guegon pins through the pistons, tops are like new

[handymanny01]

"Drip" haha, nice one Geevs! Maybe it's a mis labeled gauge? Who knows..
*update on 4JG1* Fitted 4jb1 injectors on weekend, So have gone from 5 hole nozzle @ 144 degrees spray angle, to 4 hole nozzle @ 154 degree spray angle... MUCH happier engine now! Torque is good as before, but the grey smoke has cleared up now, good power , revs out nicely, and generally sounds better,, Will still be trying other nozzles and pump set ups, so stay posted!

[handymanny01]

Dyno run with the 4jh1 injectors ... you can see the solid hit of power and torque,,, then it just can't burn the fuel properly,,, Will book a dyno run with the 4jb1 injectors and post results,,, expect to see much better result! ,,,, (sorry, pic is kinda fuzzy) red and green runs are 4jg1, the blue line was the old 4jg2 on 20lb and maxed out standard pump ,,,

[paulthepilot5]

isuzurob wrote:Its cooler on top of the piston with water and oil sqirters, manifold is just raw heat, and yes its 1200 degrees Celsius with a vdo gauge not cheap rubbish, at 600 it's slow as anything as I said fuel=power and that's what I aim for, from memory turbine wheel is 11 blade and compressor is 12/6 blade and 63mm/48mm, that's off the top of my head, everyone says 650 is safe when talking to tuners but no one really knows what things can handle, as I said 2 years of absolute abuse at 1200 degrees c and punched the guegon pins through the pistons, tops are like new
Isuzurob, What sort of fueling and AFR are you running to get that? What sort of load to get there is that just on a dyno run or holding flat up a hill?
Cheers

[isuzurob]

It has a full custom 12mm pump, only factory part is the housing, and custom single spring injectors, temps are normal road driving and towing big trailers

[paulthepilot5]

isuzurob wrote:It has a full custom 12mm pump, only factory part is the housing, and custom single spring injectors, temps are normal road driving and towing big trailers

Man that seems so hot for the setup like that even for pre turbo. You 100% sure the gauge isn’t in error?. I’ve tipped a lot of fuel into mine with modded 12mm and +50% oversized injectors, drive pressure isn’t crash hot either, never seen pre turbo temps over 750, that was towing.

[geeves]

Only one way to test the probe/gauge. A butane blow torch gives 1400C. When that temperature was first quoted it was questioned but most people use a short probe which means the exhaust loses heat to the manifold but a longer probe could be in uncooled gas. Even so I would love to set up a camera to video that manifold/turbo on a hard run. Its going to be yellow

[isuzurob]

I use autometer gauges not cheap rubbish, keep putting fuel in it will get way hotter than what I said, ie seen the manifold go white from the heat, turbo builder was worried it would melt the wheel