Builds Isuzu 4BD1T Lexus LX450 (Land Cruiser) Build (5 Viewers)

[Wheelingnoob]

I would much rather adjust things in the engine bay including adjusting drive shaft lengths to make this work than rear mount a turbo. I personally believe its a waste of the turbo putting it back there.

Remember this thread is being updated daily with the issues I find and "think" I may run into. Whether or not its an actual issue is to be seen once I measure things up. I'm simply posting all my thought's and finding as I go so people have an idea of what is involved with a swap like this. I do not want to sugar coat anything thing and leave an impression its a simple bolt in buy not covering the hurdles along the way. Doing so I hope will eliminate a bunch of questions about the swap once its done as well.

 

[Wheelingnoob]

I think intake in the rear would work. Mine is that way, and it looks like it would work for you also.

Here is a shot of my install, it looks like both turbos are in about the same location. As an idea, maybe locate a stock Isuzu intake pipe and modify it to allow a band clamp to your turbo? It looks like it would fit and tucks in well. I know the intake pipe may not be the best flowing, but the shape helps clearing the firewall and bolts nicely to the engine.

As usual, the project looks great.

Carry on.

Doug

Take a look at my build thread for some ideas on the turbo. I had similar problems on my FJ60.

I ended up folding it up next to the valve cover and make a basic but strong brake booster spacer to give the actuator clearance. I also had to cut away part of the firewall and having an intake thing made. So far it's worked great!

Thanks guys that's what I am planing on now I think I have room to fit a tight rad 90* elbow onto the inlet of the turbo, its more the amount the cover sticks out form the side of the engine towards to booster I'm worried about.

What Polar bear was talking about is putting the turbo all the way in the back of the truck where the spare would normally go and I am not going to do that.

All the input is welcome though, I appreciate all the ideas.

 

[Dazed]

I think intake in the rear would work. Mine is that way, and it looks like it would work for you also.

Here is a shot of my install, it looks like both turbos are in about the same location. As an idea, maybe locate a stock Isuzu intake pipe and modify it to allow a band clamp to your turbo? It looks like it would fit and tucks in well. I know the intake pipe may not be the best flowing, but the shape helps clearing the firewall and bolts nicely to the engine.

As usual, the project looks great.

Carry on.

Doug

I have one of these stock pipes if you're interested.

 

[Wheelingnoob]

I have one of these stock pipes if you're interested.

Thanks Mitch I may take you up on that. I want to get the engine in the engine bay before I buy any more parts for the turbo. I will let you know though as soon as I do if I need it.

 

[Timpanogos Slim]

Thanks Mitch I may take you up on that. I want to get the engine in the engine bay before I buy any more parts for the turbo. I will let you know though as soon as I do if I need it.

heck, I know some BMW tuners who have built a turboed E30 with not so much as cone filter or even a big wad of reticulated foam stuck to the mouth of the turbo yet.

They don't drive it much, but they haven't seemed concerned about it. For months.

You'll want something installed before you do your break-in, probably, but i certainly wouldn't sweat it until it's in the engine bay.

It would be kinda neat to somehow mate it to the stock airbox, allowing it to use the stock snorkel if you plan on water crossings.

 

[Wheelingnoob]

heck, I know some BMW tuners who have built a turboed E30 with not so much as cone filter or even a big wad of reticulated foam stuck to the mouth of the turbo yet.

They don't drive it much, but they haven't seemed concerned about it. For months.

You'll want something installed before you do your break-in, probably, but i certainly wouldn't sweat it until it's in the engine bay.

It would be kinda neat to somehow mate it to the stock airbox, allowing it to use the stock snorkel if you plan on water crossings.

Yeah I ran one of my Supra engines with out an air filter at the race track. it may "seem ok" but trust me it does a number on the engine and the turbo.

I do not plan to run this on the road with out a filter, short running on the stand or in the engine bay will be fine with out.

I do plan to retain the factory airbox, no plans to run anything different there. I want to retain the natural cyclonic filtering of the factory box and eventually fit a snorkle.

 

[Timpanogos Slim]

Yeah I ran one of my Supra engines with out an air filter at the race track. it may "seem ok" but trust me it does a number on the engine and the turbo.

I do not plan to run this on the road with out a filter, short running on the stand or in the engine bay will be fine with out.

I do plan to retain the factory airbox, no plans to run anything different there. I want to retain the natural cyclonic filtering of the factory box and eventually fit a snorkle.

Yeah. I recall reading in the history texts that the first rally series with forced induction motors in it had only one forced induction engine even finish the race. Because it's driver assumed he had a fuel delivery issue and had his navigator squirt gasoline into the supercharger.

Everyone else had an engine completely wedged with road grime. His was just mostly wedged.

 

[gerg]

I was reading about when cummins was racing in the indy 500 in the 50s and broke records with a turbo diesel. Its was faster in qualifying than jag and porshe, blowing them away. Well It couldnt finish the race purely duel to sucking crap off the track and clogged the intake and put them out of the race. They thought that putting the intake close to the track on the bottom of the car would give it lots of air. Well... it gave it lots of little pieces of tires as too. I cant imagine if it didnt have a filter. The turbo would have completely come unglued.

Its a great read for those that love Diesels... which is like everyone!
http://www.dieselpowermag.com/features/0808dp_cummins_diesel_race_car/viewall.html

 

[Dougal]

Doesn't it also maximize turbo lag?

Yes. While minimising boost and losing most of the heat energy that drives the turbine.

Rear mounted turbos are a complete waste of time.

 

[Polar Bear]

Yes. While minimising boost and losing most of the heat energy that drives the turbine.

Rear mounted turbos are a complete waste of time.

Ahhh.... never mind. Back to my corner

 

[gerg]

It would be interesting to see how much drive pressure rear mount turbos run vs boost. If you knew that it would give you an idea of effeciency. Ive never seen that and am quite cureous.

 

[Wheelingnoob]

Years a go when the rear turbo's where all the rage (about 10min) I had a customer come into the shop I worked at with one. He was raving about how great it was and how much to woke up his car but explained how recently it was feeling slower and making strange noises. Turned out the $1500 a piece catalytic converters did not like the rear turbo and tried to exit through said turbo. We took it all apart and rebuilt the turbo, deleted the cats app on his request and he drove away happy.

I drove the car on a test drive after and I have to say it was the worse turbo lag I have ever experienced. When it did boost it felt weak and I was very underwhelmed. He said it was the best thing ever I guess it just depends on what your bench mark is.

I would never recommend anyone do it.

 

[Dougal]

It would be interesting to see how much drive pressure rear mount turbos run vs boost. If you knew that it would give you an idea of effeciency. Ive never seen that and am quite cureous.

Let me run some numbers for the sake of the curious.

19psi boost on a 4Bd1T at 3000rpm.
With a 70% efficient turbo compressor, 60% effective intercooler, 65% efficient turbine and 700C EGT you end up with about 25.6psi drive pressure and the wastegate will be open to divert about 20% of the flow around the turbine.
Including about 2psi exhaust backpressure which I already account for in the calcs.

If we were to lose 200C exhaust temp on the way, the wastegate has to shut almost completely and we hit 28psi drive pressure.
If we were to lose another 45C (455C at the turbo inlet) then the wastegate needs clamped shut and we're at 29psi drive pressure.

Any further temperature drop and you can't even make your 19psi boost with the 0.49 A/R turbine housing.

Keep in mind this is just steady state. It's the transitions that really suck. How long do you need to be on power for the turbine inlet at the back of the vehicle to even hit 450C? In winter it might not ever happen.

 

[Polar Bear]

Let me run some numbers for the sake of the curious.

19psi boost on a 4Bd1T at 3000rpm.
With a 70% efficient turbo compressor, 60% effective intercooler, 65% efficient turbine and 700C EGT you end up with about 25.6psi drive pressure and the wastegate will be open to divert about 20% of the flow around the turbine.
Including about 2psi exhaust backpressure which I already account for in the calcs.

If we were to lose 200C exhaust temp on the way, the wastegate has to shut almost completely and we hit 28psi drive pressure.
If we were to lose another 45C (455C at the turbo inlet) then the wastegate needs clamped shut and we're at 29psi drive pressure.

Any further temperature drop and you can't even make your 19psi boost with the 0.49 A/R turbine housing.

Keep in mind this is just steady state. It's the transitions that really suck. How long do you need to be on power for the turbine inlet at the back of the vehicle to even hit 450C? In winter it might not ever happen.

Wow. Best argument I've heard against a rear mount. Thanks for sharing the knowledge!

Dougal, does your brain hurt from all that turbo goodness floating around in there? =-O

 

[Dougal]

Dougal, does your brain hurt from all that turbo goodness floating around in there? =-O

Yes. Seriously. I've given myself many hot aching headaches over this subject.

 

[gerg]

Ahh so I wasnt wanting to give you a head ache Doug. Nice explanation by the way. Put a few exhaust leaks in there and it would get nasty pretty quick. Would make marginaly more power than the little turbo whistle thingy I removed from my tail pipe when I bought my new to me 80.

 

[Wheelingnoob]

Far to much talk with out pictures.

Today I had a half day to work on the engine. Goal for this weekend it to get it running. So I needed to look at my exhaust manifold and get it modded to work with the larger compressor cover on the 19T. So first I have settled on keeping the turbo rear facing, makes everything so much easier. So with that on mind I need to cut a few bits off the manifold, namely two cast threaded bolt stand off's.

This was the one keeping me from clocking the compressor outlet so it needed to go.



Nice and low pro now.



Next was this one, it was with in 1mm of the turbine outlet flange so I needed to trim it down.



Lots of room now.



Then I took both the turbine housing and manifold and ceramic coated them. I sand blasted them both first then dunked them in a bucket of white gas to get rid of any oil and wax. I needed to brush a few areas on the exhaust manifold to get the last of the shipping wax off.

Then I laid them out and used my small siphon gun to spray on the coating.







Tuned out well, the trick with this stuff is to not make it thick, it just needs to be .001 to .005 thick. Any more and it will just bake off.

Tomorrow I plan to get the turbo clocked and re installed then take out the glow plugs and prime the oil system. From there its just a matter of seeing if it will fire.

Feels good to be almost done the rebuild of the engine, took much longer than I had planned but now I know its done with quality parts and nothing should need attention for a long time.

 

[Wheelingnoob]

Well the engine started right up. Good news!

Engine is missing and belching white smoke again. Bad news.

I have no clue why, only thing i can think would be causing this is the injection pump (only part that has not been rebuilt). It really seams like its sucking air over 1500rpm.

I ran the engine far linger than i ever wanted too and have a feeling i have totally washed down my cylinders with fuel now.

Bit pissed I must say.

Wish I had sent the pump out in the 4 months it was off.

 

[Dougal]

I wouldn't stress about that too much now. Once the cooling system and everything is in, you'll be in a much better situation to trouble shoot that.

 

[Wheelingnoob]

I wouldn't stress about that too much now. Once the cooling system and everything is in, you'll be in a much better situation to trouble shoot that.

Yeah I had the rad and cooling system full. The only time it did not smoke like mad was when it was run off the diesel purge. On diesel its belching white smoke like crazy. Tried everything i could think of. My issue with putting it in the way it is now is getting that pump out once in the engine bay is going to be an unholy pain in the ass. Its already going to be bad with my filter relocation in the way requiring removal. Any ideas? Just do not want to wash the cylinders down any more. Hate putting it in after all this work knowing i have an issue somewhere. Could the lift pump be not providing enough pressure?