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4jg1t "franken-engine"

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Re: 4jg1t "franken-engine"

Postby handymanny01 » Fri Jan 17, 2020 10:33 pm

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! :D
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Re: 4jg1t "franken-engine"

Postby geeves » Sun Jan 19, 2020 6:12 am

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
Sanding your knuckles before starting work can help. That way you cant skin them
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Re: 4jg1t "franken-engine"

Postby isuzurob » Sun Jan 19, 2020 8:16 am

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
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Re: 4jg1t "franken-engine"

Postby handymanny01 » Sun Jan 19, 2020 8:37 am

"Drip" haha, nice one Geevs! :lol: 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!
Last edited by handymanny01 on Wed Jul 01, 2020 4:22 pm, edited 1 time in total.
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Re: 4jg1t "franken-engine"

Postby handymanny01 » Mon Jan 20, 2020 6:37 pm

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 ,,,
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Re: 4jg1t "franken-engine"

Postby paulthepilot5 » Thu Jun 11, 2020 9:43 pm

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
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Re: 4jg1t "franken-engine"

Postby isuzurob » Fri Jun 12, 2020 4:14 pm

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
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Re: 4jg1t "franken-engine"

Postby paulthepilot5 » Fri Jun 12, 2020 8:38 pm

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.
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Re: 4jg1t "franken-engine"

Postby geeves » Sat Jun 13, 2020 7:40 am

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
Sanding your knuckles before starting work can help. That way you cant skin them
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Re: 4jg1t "franken-engine"

Postby isuzurob » Sat Jun 13, 2020 5:22 pm

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
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Re: 4jg1t "franken-engine"

Postby paulthepilot5 » Sat Jun 13, 2020 7:17 pm

isuzurob wrote: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


Even good gauges can fail though. What sort of power and torque are you getting from that setup?
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Re: 4jg1t "franken-engine"

Postby isuzurob » Sun Jun 14, 2020 5:45 pm

Have run 3 different brand egt and all well over 900 degree celcius, never run on a dyno, has average power, goes far better than my stock 4jj1 colorado and have blown 5 gearboxes in it and 3 clutches to pieces so must have some power
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Re: 4jg1t "franken-engine"

Postby paulthepilot5 » Sun Jun 14, 2020 7:36 pm

isuzurob wrote:Have run 3 different brand egt and all well over 900 degree celcius, never run on a dyno, has average power, goes far better than my stock 4jj1 colorado and have blown 5 gearboxes in it and 3 clutches to pieces so must have some power

Yes clutches are a issue with the JB1 when pushing them, too small diameter for the torque really. Went through several types before I could find one that did the job. NPC cushioned ceramic with a doubled up diaphragm spring is what solved my problems. What has been the failure on your gearboxes? I have dramas with the input shafts snapping I believe it’s the weakest part. Even so they are surprisingly strong gearbox given its size and weight particularly behind a 4cylinder diesel.
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Re: 4jg1t "franken-engine"

Postby isuzurob » Mon Jun 15, 2020 4:09 pm

I run a 8 button clutch plate and custom 3000lb pressure plate, also running a bigger diameter flywheel to run bigger clutch setup, normally strips 5th gear first and spreads the main and lay shafts apart, then just works it's way down till I only have fourth to limp home
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Re: 4jg1t "franken-engine"

Postby paulthepilot5 » Fri Jun 26, 2020 8:56 pm

handymanny01 wrote: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 ,,,
.

The 4JH1 injectors are a smaller nozzle oriffice than the JB1 nozzles. Might explain the better low rpm and running out top end. The +50 nozzles I’m running on my JB1 perform mid to top end more so than low rpm.
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Vehicle: 1995 Isuzu Rodeo 2.8d
Compound twin Turbo
12mm fuel Pump
+50 injectors
Water/meth injection
14s 1/4 Mile

Re: 4jg1t "franken-engine"

Postby handymanny01 » Tue Jun 30, 2020 4:40 pm

Hey Paul, I think it was just due to the terrible mismatch between the 4jg1 pistons and the 4jh1 injectors... 4jg1 is a 152 degree injector spray angle, 4jh1 is 144 degrees ... the 4jh1 injectors were flowing plenty of fuel,,, just wasnt burning it,, Now running 4jb1 injectors,,(154 degrees) and shes MUCH happier!! A best of 112KW at wheels and 501NM on 33 inch tyres, so pretty respectable.... next couple of runs will be with narrow body injectors and actual 4jg1 nozzles, then some hopefully perfect nozzles from a Komatsu 6 cylinder,(these took some searching!)
And then water meth injection! yuuussssss
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Re: 4jg1t "franken-engine"

Postby paulthepilot5 » Thu Jul 02, 2020 8:47 pm

Handymanny that’s some good output there now, you will see some good gains with water/meth as well, particularly top end. Seems the 6cylinder engines offer a better selection for better flowing nozzles, I’ve been looking at some Isuzu 6cyl options, what Komatsu engine nozzles were you looking at? I’m just in the process of fitting up a in-line P-Pump after doing a belt drive conversion. Going to the +50 nozzles didn’t get me anywhere near the fuel I wanted, but then they are just the 4hole nozzles. What sort of W/M setup will you be running?
paulthepilot5
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Posts: 84
Joined: Thu Apr 05, 2018 8:56 pm
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Vehicle: 1995 Isuzu Rodeo 2.8d
Compound twin Turbo
12mm fuel Pump
+50 injectors
Water/meth injection
14s 1/4 Mile

Re: 4jg1t "franken-engine"

Postby handymanny01 » Sun Jul 05, 2020 6:42 am

Hey Paul, the Komatsu nozzles are DLLA152PN009 4x.30 @ 152degrees. These are at (least in theory) the perfect nozzles for a hot rod 4JG1 Standard 4JG1 nozzles being something tiny like 4x0.17 (don't quote me on that, I just remember them being tiny) Hopefully they fit a set of narrow body 4JB1 injectors I have coming ,,, Def looking forward to the water meth! I've got bits coming from ProMeth (great selection!)in the states, have readied manifold for port injection, 4 x 95cc nozzles, For a total flow of 380cc/min @ 100 psi, or approx 700cc/min @ 200psi. Will test on dyno to see how much is needed
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