Build Isuzu 4BD1T Lexus LX450 (Land Cruiser) Build

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fabmec said:
What purpose do the springs retaining the intake manifold serve? Over boost control? Dougal do you think this could be an issue? I replaced mine with normal bolts when the engine went in.
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I checked the stiffness of these and force from the intake ports several years ago. I concluded they aren't a problem at expected boost levels and left mine on. I was running another washer for more spring pre-load prior to this.

What's your intake to your air-box Jeremy? Can you go for a drive with the air-box open?
 
Dougal said:
I checked the stiffness of these and force from the intake ports several years ago. I concluded they aren't a problem at expected boost levels and left mine on. I was running another washer for more spring pre-load prior to this.

What's your intake to your air-box Jeremy? Can you go for a drive with the air-box open?
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Yeah I can test that. Its 3" piping from a 3.75" opening air box.
 
Dougal said:
Well we've ruled out:
Fuelling
Intake vacuum.
Exhaust restriction.
Timing.

I'd be pulling the turbo.
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Yeah, with the airfilter top off the turbo did not sound very good. Almoat a mix of coffee grinder and turbo whistle.

Im also going to pull and replace both fuel filters becouse I think with 180cc/1000 and only 25psi on this turbo it shoukd be alot smokier and hotter EGT's.
 
ForealBoreal said:
Whats that code for?
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Its code for im to lazy to pull it right now so am out enjoying it instead. Today with the converter locked in 4th I got it to 29psi up a long steep hill (think snowshead hill on the coke) doing 120kms/hr up the hill. EGT's where frightning but I kept my foot in it. I can safly say I have my cooling system solid now. [emoji6]

I filled up when I got back and on a tank that was 2/3rds short around town jumps and dyno pulls I avarageed 16.7L/100kms un corrected (my speedo is 10% slow).

I think im actually fighting a transmission that is soaking up a lot of power. If I lock the converter now in 3rd and plant my food at 1600rpm by the time I get to 2000rpm its well over 20psi and accelerating hard. If I do the same with the converter unlocked I get 13pai by 2000rpm and it feels much slower.

On another note I think I am making enough power that the converter lock up is now starting the slip, if I roll into it the truck starts the shake violently. If I do the same unlocked its slooth.
 
Was kind of wondering how your torque converter would hold in lockup in lower gears. Could be the tranny clutches too though i would think if the t/c is locked. At least that is what i think mine is if i fuel it right up. Still ,wish i had lockup ability like yours .
 
Im going to try increasing the line pressure next with a tighter kickdown cable. Issue is if I go much tighter it will not shift at wide open theottle.

I dont see why tranny would be having issue its got over 200k miles on it........;)
 
Sorry I forgot what transmission you used? 440? 442? Do they have a pressure regulator like the A343F that has 3 positions for fluid pressure? You could try just clicking it up to the next setting if you didn't do a shift kit.
 
scottryana said:
Sorry I forgot what transmission you used? 440? 442? Do they have a pressure regulator like the A343F that has 3 positions for fluid pressure? You could try just clicking it up to the next setting if you didn't do a shift kit.
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Its an A440, no dial for line pressure. Its pressure is regulated my the kickdown cable. Its got a upgraded valve body in it already.
 
I have mine quite tight , way more than stock. If i pedal not even half way it will downshift. Mines probably not comparing apples to apples but i only need half the throttle to drive normal.Something to think about is ,i was thinking if i needed more i was just going to change the radius a little tighter on the throttle arm. In princible that should do both , more pressure and a little laxed on the down shift..
 
wrongway around said:
I have mine quite tight , way more than stock. If i pedal not even half way it will downshift. Mines probably not comparing apples to apples but i only need half the throttle to drive normal.Something to think about is ,i was thinking if i needed more i was just going to change the radius a little tighter on the throttle arm. In princible that should do both , more pressure and a little laxed on the down shift..
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Yeah I needed to back mine way off to shift with anything over 1/2 throttle. Issue is im worried its not moving enough to increae line pressure enough.
 
ozwallaby said:
WN are you running an A440 converter or did you go with a 442 converter on the 440 tranny.... think I read somewhere on mud, 442 converters are a more efficient design so less fluid heat at least....
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Nope, its a rebuilt and stalled down A440 converter. The a442 converter is much more efficent. The single biggest thing that leads to A440's failing is the heat generated by the crappy stock converter. My modified valve body allows lock up electronically when ever I want above about 30kms/hr. My trans temp never gets over 150f in normal driving. In slowgoing off road its gotten to 200f but no higher. Heat is not an issue I have had yet on this trans.
 
This is an old fuel trick for plunger and fuel switching at higher revs that can be used in many ways . Basically if you draw a circle , the outer circumference is where your cable is now . If you put a smaller circled lever for your cable you would still have initial pressure start and yet the more your into the throttle it wont downshift. I've even used this principle to point of making it have a cam lobe high or low spot to create or stall the effect until full throttle.
Can i ask ? What if any is the difference in the throttle throw from the isuzu to the fz ? Is your tranny cable limiting the pump throw? what linkage setup did you use?
I highly doubt this is your converter unless it is one of those (you get what you pay for things) especially if its not creating heat. Im assumeing you have put it in low and loaded it up in park reverse neutral forward in low range to check all your mounts and drive line right.
 
I have changed the cam throgh for the kickdown already. It is shorter and the cable is loaded more innicially than stock. A smaller cam circle.

The travel of the izusu throttle is shorter than the 1fz. Im uszing 1fz throttle cable to 3fe cruise contole acctuayor then from there to the factory isuzu linkage. The Isuzu is getting full throttle I have checked that a few times.
 
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