.. 80 Series Diesels What I've Learned thus far .. (1 Viewer)

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I was attempting to be conservative with a 15-20 lb boost .. Is it your experience that 25 lbs is completely safe with the appropriate intercooler ? .. I have seen many intercooler options .. There are two main camps W2A and A2A intercoolers .. One camp says that A2A are more reliable from the standpoint of no plumbing but are 30% better depending on how you cool the water .. I would like to lean towards the more reliable / safer side if possible and if I could have a system whose boost is adjustable from 15 - 25 lbs of boost without mucking with the injector pump or injectors all the better .. If all I have to do is a minor adjustment to the injector pump and I can then run 20-25 lbs then this is the safer path .. I have been reading that the most efficient A2A intercooler runs in front of the radiator but fans should be used to decrease the temperature of cool air .. Should I also consider a triple layer high efficiency engine coolant radiator as well ? .. Again, my reasons for all these modification is to improve upon reliability & increased longevity ..
 
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People change suspension usually because they intend to use the truck outside if the parameters it was engineered for.
There is a measurable difference in performance or capability.
Swapping a timing belt for a timing chain is moving away from something that reliably performs within its designed parameters.
I've replaced multiple timing belts either on new to me cruisers where maintenance history is unknown, or at the 100k km service interval.
Is a simple, low cost maintenance item. Is achievable in about an hour. Takes about a :banana::banana:level of mechanical aptitude to get right.

To swap to a chain, would require a considerable amount of custom parts, cost and time and effort would outweigh the cost, time, effort required for maintenance of a belt.
Its something that very few people would ever see a benefit from in terms of cost or longevity of the engine as whole

Both have failures within their designed life period, both very rarely.

The premise of me asking about a Timing Chain is that chains don't fail .. The cost of such an upgrade I was not aware of .. I have read that the 1HD-T & 1HD-TF's engines have run up to 1 million km .. That is impressive given that the 1VD-FTV 4.5L 8cyl engines say they are designed to run 250,000 - 300,000 km .. I believe this speaks volume regarding lower rev'ing longer stroke engines vs Toyota move to decrease motor life .. This was the reason for me choosing the 1HD-FT 80 series ..

Regarding Transmission upgrade there is an Aussie Transmission company that has better valve bodies that help the engines to shift better and run cooler .. I have also read about the improved torque converter and lock up kits .. As this applies to running a trailer / heavy load, I would like to know if these mod are necessary ..
 

AussieHJCruza

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I was attempting to be conservative with a 15-20 lb boost .. Is it your experience that 25 lbs is completely safe with the appropriate intercooler ? .. I have seen many intercooler options .. There are two main camps W2A and A2A intercoolers .. One camp says that A2A are more reliable from the standpoint of no plumbing but are 30% better depending on how you cool the water .. I would like to lean towards the more reliable / safer side if possible and if I could have a system whose boost is adjustable from 15 - 25 lbs of boost without mucking with the injector pump or injectors all the better .. If all I have to do is a minor adjustment to the injector pump and I can then run 20-25 lbs then this is the safer path .. I have been reading that the most efficient A2A intercooler runs in front of the radiator but fans should be used to decrease the temperature of cool air .. Should I also consider a triple layer high efficiency engine coolant radiator as well ? .. Again, my reasons for all these modification is to improve upon reliability & increased longevity ..
50 psi won't hurt it with head studs and a decent tune. Heat kills a diesel, not boost. Rich is hot in a diesel, it can run infinitely lean.
The Yanmar 6LPA-STC (which is basically a 1HDFT with a different fuel pump and turbo and endless amounts of water for an intercooler is rated at 315 HP out of the box.

Yes you want a front mount air to air intercooler. With a properly working fan clutch I wouldn't see the need for separate fans.

On radiator, there's nothing wrong with the stock one as such. I went to a 3 core Adrad with welded tanks because the original was 20 years old and I wanted to replace it.

Wholesale automatics make valve bodies, transcoolers etc. Would suggest a transmission cooler at a minimum. Heat is the enemy of an auto and you want to be able to shed it as fast as possible. Invest in a trans temperature gauge as well as boost and EGT, it will change the way you drive considerably.

On the variable boost thing, don't bother. Have 1 tune, get it right and run with it. All the diesels that have spent time on my dyno don't have heat issues. If the timing is right and tune is right and the cooling system is up to scratch, a 1HD doesn't run hot.
 

mudgudgeon

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I would like to lean towards the more reliable / safer side if possible and if I could have a system whose boost is adjustable from 15 - 25 lbs of boost without mucking with the injector pump or injectors

Running two levels of boost is pointless with a mechaically injected engine.

You'll need to tune so it runs safely at the lower boost level.

This means tuning injection so fuelling levels arent too high. Too much fuel equals high EGT, and excess combustion heat in the head and coolant.
Increasing boost will only increase power if there's also more fuel added to make use of the additional oxygen.
Power output is limited by how much fuel you can burn. Stuff more air in, you can burn more fuel.
If your tune is too rich, increasing boost will help reduce combustion temperatures.
 
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Off the belt/chain topic, but I would have to disagree that diesels offer more compression braking.

While it’s true that compression ratios are typically higher in diesels, compression ratio is not a large influence on braking IMO. Yes, it does take a lot of energy to compress at 22:1, but on the converse, most of the energy is released on the expansion.

I believe gasoline to have stronger engine braking naturally due to the fact they are throttled. Hence the reason large diesel trucks uses a Jake brake (simulating vacuum since a diesel naturally lacks a vacuum).
 

SNLC

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I have personally seen a 1HZ powered (timing belt) Cruiser with 860,000kms on it. There was a hole worn in the metal gas pedal, engine kept going.

I have seen others with over 600,000kms.

Cheers
 
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50 psi won't hurt it with head studs and a decent tune. Heat kills a diesel, not boost. Rich is hot in a diesel, it can run infinitely lean.
The Yanmar 6LPA-STC (which is basically a 1HDFT with a different fuel pump and turbo and endless amounts of water for an intercooler is rated at 315 HP out of the box.

Yes you want a front mount air to air intercooler. With a properly working fan clutch I wouldn't see the need for separate fans.

On radiator, there's nothing wrong with the stock one as such. I went to a 3 core Adrad with welded tanks because the original was 20 years old and I wanted to replace it.

Wholesale automatics make valve bodies, transcoolers etc. Would suggest a transmission cooler at a minimum. Heat is the enemy of an auto and you want to be able to shed it as fast as possible. Invest in a trans temperature gauge as well as boost and EGT, it will change the way you drive considerably.

On the variable boost thing, don't bother. Have 1 tune, get it right and run with it. All the diesels that have spent time on my dyno don't have heat issues. If the timing is right and tune is right and the cooling system is up to scratch, a 1HD doesn't run hot.
Thank you .. This is great information ..

You put the GTurbo Red on you vehicle running at 26 lbs .. Did you have to do any fuel system adjustments / mods ?
 

mudgudgeon

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If you want to know what's been learnt about getting more power reliably from these engines, here's a few good threads to read through.
It's well understood what makes these things come alive, whether with stock turbo and stock pump, or modified.

You can get huge increases from the stock turbo and fuel pump with exhaust upgrade, increase in boost, and increase in fuelling, and intercooler.
The stock fuel pump will support a huge increase in output.




 

AussieHJCruza

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Theoretically the stock pump provides enough fuel for 150rwkw but if she's done a few km, the mechanical advance won't keep up - I had this problem with mine, she made good torque but fell flat after about 2200 rpm and EGT went through the roof.

You're not reinventing the wheel here @phatman81 plenty of worked 1HD engines getting around so what @mudgudgeon has given you is very worthwhile reading
 

Romer

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So this post got off track a bit with some personal attacks and then got back on track so I am going to leave it. I was about to delete many posts in the middle that were just barbs at one another

so for this thread to stay open, please be respectful and on track and lets not make stuff up either.

To the @phatman81 you havent been here long and when onur presented data showing you were incorrect as you posted petrel data as diesel you told him he should have posted that earlier. That comes across poorly. Many of your posts had a condescending tone even when you were wrong or just fishing. your first posts were awesome and your last posts have been great as well.

So as the Moderator of this forum, please behave and keep up the dialogue respectfully. Don't make me put my drink down get out of my chair and moderate this thread!

Your friendly 80's moderator

 
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Off the belt/chain topic, but I would have to disagree that diesels offer more compression braking.

While it’s true that compression ratios are typically higher in diesels, compression ratio is not a large influence on braking IMO. Yes, it does take a lot of energy to compress at 22:1, but on the converse, most of the energy is released on the expansion.

I believe gasoline to have stronger engine braking naturally due to the fact they are throttled. Hence the reason large diesel trucks uses a Jake brake (simulating vacuum since a diesel naturally lacks a vacuum).

Diesel engines offer considerably better engine braking due to the higher compression ratios AND they are compressing significantly more air compared to petrol which is under vacuum.

Yes, a lot of the compression energy is transferred back during expansion, but a lot of energy is converted to heat which is where the braking comes from.

Petrol engines don't offer much compression braking as the cylinder is under vacuum, meaning very little energy is converted into heat.

A Jake Brake has nothing to do with vacuum, rather its an additional valve (or sometimes opening of the standard exhaust valve) when the cylinder has reached top dead centre. Eg the air is compressed as the cylinder rises, as it reaches the top the additional valve opens releasing the compressed air meaning it doesn't push the piston down on the downstroke.

Also, there is a LOT of other misinformation in this thread, anyone reading should take most things writing with a large pile of salt...
 

mudgudgeon

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Diesel engines offer considerably better engine braking due to the higher compression ratios AND they are compressing significantly more air compared to petrol which is under vacuum.

Yes, a lot of the compression energy is transferred back during expansion, but a lot of energy is converted to heat which is where the braking comes from.

Petrol engines don't offer much compression braking as the cylinder is under vacuum, meaning very little energy is converted into heat.

A Jake Brake has nothing to do with vacuum, rather its an additional valve (or sometimes opening of the standard exhaust valve) when the cylinder has reached top dead centre. Eg the air is compressed as the cylinder rises, as it reaches the top the additional valve opens releasing the compressed air meaning it doesn't push the piston down on the downstroke.

Also, there is a LOT of other misinformation in this thread, anyone reading should take most things writing with a large pile of salt...

Well put.
 

swankstar

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Going to stir the pot here a little: some of ya'll aren't super familiar with physics, and it shows. Below are a couple helpful links with some info.

Engineering Explained - What Is Engine Braking? What Is A Jake Brake?

In short:

Gas engine braking comes from vacuum created by the throttle body when the piston is trying to pull air past the butterfly valve on the intake stroke (ie, creating vacuum)

Diesel engine braking comes ONLY WHEN either:
1. the "throttle body" from a gas engine is put in the exhaust pipe to restrict airflow through the engine. This causes work do be done when the piston has to push air past the butterfly valve on the exhaust stroke. Kinda like the old "banana in the tailpipe" trick in beverly hills cop or whatever it was.​
OR​
2. the exhaust valve is opened before the pressure built during the compression cycle can be used by the engine to push the piston back down. This means the piston is used to squish air on the compression stroke (doing a lot of work), then all that compressed air is released before the exhaust stroke (before the power stroke even).
Without either of those two things being involved, the diesel piston is simply squishing air, then that same squished air is pushing the piston back down.​
 

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