PLEASE, HELP A NON MECHANIC GUY HAVE SOME SIMPLE, BASIC PERFORMANCE UPGRADE WORK DONE ON HIS 12H-T ENGINE (1 Viewer)

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Hello everyone.

(Sorry for the long post)

  • Let’s say I am no mechanic at all, which is the case. Just a regular dude passionate about the 12 H-T engine (which is the case too J ) . Let’s further suppose I live in an environment with limited or no access to expert knowledge on 12H-T (that’s been the case so far). If I needed to have any “ordinary” mechanics do some simple, basic work on my 12H-T performance upgrades based on my own layman’s checklist what would you AMEND, ADD to or REMOVE from that checklist (here below)?

  • Here’s my layman’s 13-point performance upgrades Checklist for my 12H-T .
1) Engine rebuilt. Status: Done

  • I don’t know if that can be called a rebuild.
  • Actually, I have been able to source a 12H-T from which the previous owner had removed the turbo a long time ago. I have no idea of how many kilometers were on the clock but the engine looked fine (no cracks in the cylinders, STD crankshaft, etc.). The major apparent issue was the damaged pistons. The previous owner advised to merely replace the “bad” pistons as he was confident with all else being just fine. Seems have kept the engine on the ground safely from water.
  • So, the job that has been done so far is that we replaced the pistons along with what my research shows is called “rod bearing shell” and also, I think, side crankshaft shims. (Hey, remember, I said I was no mechanic, just having a few friends around to help in)

  • All in all, the engine had what seemed a good restart!
2) The Alfin pistons. Status: Replacement Done

  • I don’t have a clue what they look like. I read about a few tips on how to recognize alfin from non alfin piston, but too lazy of a layman to check that so, I read TEIKIN was making good alfin Pistons. So, we purchased pistons (13101-68020) & RINGs (13011-68020/13013-68030). I can just hope they are as good as I heard about.

  • 3) The Injection pump: Status: Replacement done with a seemingly good working one.

  • The previous Injection pump was did work fine at the engine first (re)start as it would cause the engine to accelerate endlessly. Sourcing a new injection pump is near impossible as they are very expensive on the net. Also, I am not sure who can do the recondition job locally. Luckily, I had a spare one that we used rather, and the engine restarted fine. Performance wide, I still can’t tell if that spare one is working at is best. I am not sure who can do the checks locally. It seems to work fine (no smoke!!!). I’d rather not give it to a so-called expert who may damage it.

4) The Injectors: Status: Replacement done with a seemingly good working ones.

  • Sourcing a new set is near impossible as they are very expensive on the net. Also, I am not sure who can do the recondition job locally. However, they seem ok but maybe I can’t really tell until the engine is put back in the car and driven for a while.
  • The injector nozzles seem to be easier to source than the complete injectors. I don’t don’t know if it is worth it to buy a set of nozzles and replace them in the current injectors. Don’t know.
5) Turning up the fuel: More Fuel + More Air = More Power. Status: I’d rather NOT to.

  • I read a bit here and there about “increasing fuel and boost levels from std values” for more power. I’d like to but here too, I am not sure who can do that locally. Then, I’d rather not take any risk of damaging my hard-won 12H-T

6) The Turbo: More Fuel + More Air = More Power. Status: already sourced, installation planned for very soon.
As said earlier, the previous owner had removed the turbo for “oil-related issues”. I don’t understand much of what he meant by that but I intend to put the turbo back. I have purchased a more modern turbo from Wink 4x4 - Engineered Performance - http://www.wink4x4.com
(I don’t know if they’re any good, some forums say they are), but I mostly fell for their brief description lines on their website J​
Hi-flow turbos​
We supply a fully customized engineered turbocharger range, fitted into the OEM Toyota CT26 housing. Both turbine and compressor wheels on the turbocharger are custom designed. The original CT26 technology is about 15-30 years old. Our new design contains modern technology and is more responsive to give your Land Cruiser better drivability.
All turbochargers are more efficient and designed to run at higher boost levels with even lower intake temperatures, due to higher efficiency. The bearing system is upgraded with 360 degree thrust bearings and can hold up to 30psi (2bar) of turbo pressure. (Wink 4x4 - Turbochargers - http://www.wink4x4.com/turbo/)​


7) The Compression test. Status: Not done. I don’t have the knowledge nor the tool

I read it was important to do it before considering putting a turbo. I don’t know if it applies to 12H-T as this engine is built to have a Turbo. However, it is said that doing the Compression test on a 12H-T is not that simple (I challenged the mechanics here from my readings, they seemed lost)… Moreover, I searched the net and could NOT find a kit/tool that would make the job easy. Any link to a kit/tool or simple technique?​

8) The Intercooler: More Fuel + More “COLD Air” = More Power. Status: already sourced, installation planned for very soon

I read a bit about intercoolers. They seem a good upgrade for 12H-T as this engine was produced before the “invention” of intercoolers.​
I’d for a Top mount, just because it seems easier to install (closer to the engine, less piping) and looks more badass J​
Something silly I’d also like to try is collecting in a small reservoir the cold water from the A/C, then recycling/(and pumping) it to the engine bay through a sprayer over the intercooler and back to the reservoir to mix up with the continuously pouring A/C cold water again. I don’t know yet what it would look like or whether it would be any effect in helping the intercooler cooling the air from the turbo J​


9) The oil pump. Status: Replacement done with a seemingly good working one.

  • I read that it is always a good thing to replace the old one after rebuilding the engine. I have one brand new spare Oil pump, but the mechanic managed to convince me to keep the old one as it seems still work fine. What would you advise?
10) The Water pump. Status: Replacement done with a seemingly good working one.

  • We kept the old one though we were in a position to source a new. What would you advise?
11) A 3” inch exhaust. Status: Replacement done.

  • From readings, it seems to help improve the engine performance. So, I bought one from www.deaperformance.com.au (I would usually blindly trust products from Australia J)
12) Gauges. Status: sourcing in progress, installation planned for very soon.
  • I’m definitely going to get a few of them (pre- and post-turbo, pre- and post-intercooler)
13) The brake systems. Status: sourcing in progress, installation planned for very soon.
Regards
Boris
 
Hello everyone.

(Sorry for the long post)

  • Let’s say I am no mechanic at all, which is the case. Just a regular dude passionate about the 12 H-T engine (which is the case too J ) . Let’s further suppose I live in an environment with limited or no access to expert knowledge on 12H-T (that’s been the case so far). If I needed to have any “ordinary” mechanics do some simple, basic work on my 12H-T performance upgrades based on my own layman’s checklist what would you AMEND, ADD to or REMOVE from that checklist (here below)?

  • Here’s my layman’s 13-point performance upgrades Checklist for my 12H-T .
1) Engine rebuilt. Status: Done

  • I don’t know if that can be called a rebuild.
  • Actually, I have been able to source a 12H-T from which the previous owner had removed the turbo a long time ago. I have no idea of how many kilometers were on the clock but the engine looked fine (no cracks in the cylinders, STD crankshaft, etc.). The major apparent issue was the damaged pistons. The previous owner advised to merely replace the “bad” pistons as he was confident with all else being just fine. Seems have kept the engine on the ground safely from water.
  • So, the job that has been done so far is that we replaced the pistons along with what my research shows is called “rod bearing shell” and also, I think, side crankshaft shims. (Hey, remember, I said I was no mechanic, just having a few friends around to help in)

  • All in all, the engine had what seemed a good restart!
2) The Alfin pistons. Status: Replacement Done

  • I don’t have a clue what they look like. I read about a few tips on how to recognize alfin from non alfin piston, but too lazy of a layman to check that so, I read TEIKIN was making good alfin Pistons. So, we purchased pistons (13101-68020) & RINGs (13011-68020/13013-68030). I can just hope they are as good as I heard about.

  • 3) The Injection pump: Status: Replacement done with a seemingly good working one.

  • The previous Injection pump was did work fine at the engine first (re)start as it would cause the engine to accelerate endlessly. Sourcing a new injection pump is near impossible as they are very expensive on the net. Also, I am not sure who can do the recondition job locally. Luckily, I had a spare one that we used rather, and the engine restarted fine. Performance wide, I still can’t tell if that spare one is working at is best. I am not sure who can do the checks locally. It seems to work fine (no smoke!!!). I’d rather not give it to a so-called expert who may damage it.

4) The Injectors: Status: Replacement done with a seemingly good working ones.

  • Sourcing a new set is near impossible as they are very expensive on the net. Also, I am not sure who can do the recondition job locally. However, they seem ok but maybe I can’t really tell until the engine is put back in the car and driven for a while.
  • The injector nozzles seem to be easier to source than the complete injectors. I don’t don’t know if it is worth it to buy a set of nozzles and replace them in the current injectors. Don’t know.
5) Turning up the fuel: More Fuel + More Air = More Power. Status: I’d rather NOT to.

  • I read a bit here and there about “increasing fuel and boost levels from std values” for more power. I’d like to but here too, I am not sure who can do that locally. Then, I’d rather not take any risk of damaging my hard-won 12H-T

6) The Turbo: More Fuel + More Air = More Power. Status: already sourced, installation planned for very soon.
As said earlier, the previous owner had removed the turbo for “oil-related issues”. I don’t understand much of what he meant by that but I intend to put the turbo back. I have purchased a more modern turbo from Wink 4x4 - Engineered Performance - http://www.wink4x4.com
(I don’t know if they’re any good, some forums say they are), but I mostly fell for their brief description lines on their website J​
Hi-flow turbos​
We supply a fully customized engineered turbocharger range, fitted into the OEM Toyota CT26 housing. Both turbine and compressor wheels on the turbocharger are custom designed. The original CT26 technology is about 15-30 years old. Our new design contains modern technology and is more responsive to give your Land Cruiser better drivability.
All turbochargers are more efficient and designed to run at higher boost levels with even lower intake temperatures, due to higher efficiency. The bearing system is upgraded with 360 degree thrust bearings and can hold up to 30psi (2bar) of turbo pressure. (Wink 4x4 - Turbochargers - http://www.wink4x4.com/turbo/)​


7) The Compression test. Status: Not done. I don’t have the knowledge nor the tool

I read it was important to do it before considering putting a turbo. I don’t know if it applies to 12H-T as this engine is built to have a Turbo. However, it is said that doing the Compression test on a 12H-T is not that simple (I challenged the mechanics here from my readings, they seemed lost)… Moreover, I searched the net and could NOT find a kit/tool that would make the job easy. Any link to a kit/tool or simple technique?​

8) The Intercooler: More Fuel + More “COLD Air” = More Power. Status: already sourced, installation planned for very soon

I read a bit about intercoolers. They seem a good upgrade for 12H-T as this engine was produced before the “invention” of intercoolers.​
I’d for a Top mount, just because it seems easier to install (closer to the engine, less piping) and looks more badass J​
Something silly I’d also like to try is collecting in a small reservoir the cold water from the A/C, then recycling/(and pumping) it to the engine bay through a sprayer over the intercooler and back to the reservoir to mix up with the continuously pouring A/C cold water again. I don’t know yet what it would look like or whether it would be any effect in helping the intercooler cooling the air from the turbo J​


9) The oil pump. Status: Replacement done with a seemingly good working one.

  • I read that it is always a good thing to replace the old one after rebuilding the engine. I have one brand new spare Oil pump, but the mechanic managed to convince me to keep the old one as it seems still work fine. What would you advise?
10) The Water pump. Status: Replacement done with a seemingly good working one.

  • We kept the old one though we were in a position to source a new. What would you advise?
11) A 3” inch exhaust. Status: Replacement done.

  • From readings, it seems to help improve the engine performance. So, I bought one from www.deaperformance.com.au (I would usually blindly trust products from Australia J)
12) Gauges. Status: sourcing in progress, installation planned for very soon.
  • I’m definitely going to get a few of them (pre- and post-turbo, pre- and post-intercooler)
13) The brake systems. Status: sourcing in progress, installation planned for very soon.
Regards
Boris
alright, I took a stab at your list:
1) Engine rebuilt. Status: Done.
2) The Alfin pistons. Status: Replacement Done
3) The Injection pump: Status: Replacement done with a seemingly good working one. if it isn’t broke don’t fix it. These require a high degree of expertise to repair.

4) The Injectors: Status: Replacement done with a seemingly good working ones. I don’t know much about the injectors.

5) Turning up the fuel: More Fuel + More Air = More Power. Status: I’d rather NOT to. don’t do it. you stated that you’re not a mechanic, so it’s best to not mess with this. the stock configuration is sufficient and engineered to last a long time, when we tinker with settings it has the potential to throw that balance off. Unless you are a mechanic and do the work yourself or have lots of money to pay a good mechanic, leave the fuel and boost levels alone as stock.

6) The Turbo: More Fuel + More Air = More Power. Status: already sourced, installation planned for very soon.
the 12h-t is engineered to have a turbo charger, you need one, hopefully close to stock specs. (Wink 4x4 - Turbochargers - Wink 4x4 - Turbochargers - http://www.wink4x4.com/turbo/)

7) The Compression test. Status: Not done. I don’t have the knowledge nor the tool
it’s possible to do. Does the motor stop straight away when you turn it off? Yes, then you probably have good compression. if you had the engine rebuilt, it should have good compression.

8) The Intercooler: More Fuel + More “COLD Air” = More Power. Status: already sourced, installation planned for very soon
return it, it’s not necessary. maybe if you were going to have a bigger turbo, more fuel, bigger exhaust, etc…

9) The oil pump. Status: Replacement done with a seemingly good working one. I read that it is always a good thing to replace the old one after rebuilding the engine. I have one brand new spare Oil pump, but the mechanic managed to convince me to keep the old one as it seems still work fine. What would you advise? I’d advise to replace with a new one if it’s possible; I don’t have expert knowledge of the oil pump.

10) The Water pump. Status: Replacement done with a seemingly good working one. definitely replace the water pump

11) A 3” inch exhaust. Status: Replacement done. won’t change much without increasing boost and fuel, which isn’t necessary.

12) Gauges. Status: sourcing in progress, installation planned for very soon. oil pressure because the one in the dash probably doesn’t work, and a boost gauge

I’m definitely going to get a few of them (pre- and post-turbo, pre- and post-intercooler) what? if you’re referring to an EGT gauge, it should go preturbo in the manifold, however it’s not necessary unless you are going to increase boost and fuel and timing.

13) The brake systems. Status: sourcing in progress, installation planned for very soon. make the brakes work better, yes. I have 4runner/surf front calipers, everything else is stock. Brakes are important, recondition them to the highest level.
 
That's quite the list.

When/if you add the turbo, you will need to add a Boost Compensator to the injection pump. This allows for the injection pump to dynamically change the injection volume depending on how much boost is being produced. It's an easy and cheap add-on. Maybe your old pump already has a Boost Compensator. You mentioned that you were getting a new pump, so I'm just making sure.

Read this article for a better understanding of why a Boost Compensator is needed: Basic HOW TO - Mechanical Diesel Engine Tuning Guide - https://www.tillix.com.au/mechanical-diesel-engine-tuning/

Regarding gages, you only need two. Pre-turbo EGT (installed right into the exhaust manifold outlet where it all comes together) and boost (installed right at the intake). You don't need pre/post and all that you have listed.

Congrats on getting so much done. I bet labor is really cheap over there.
 
Best time to do the oil pump is when you rebuilt the motor. They might have done it. Otherwise you got to get the front timing cover off to do it.
 
Thanks a lot Kevin for informed guidance!
alright, I took a stab at your list:
1) Engine rebuilt. Status: Done.
2) The Alfin pistons. Status: Replacement Done
3) The Injection pump: Status: Replacement done with a seemingly good working one. if it isn’t broke don’t fix it. These require a high degree of expertise to repair.

4) The Injectors: Status: Replacement done with a seemingly good working ones. I don’t know much about the injectors.

5) Turning up the fuel: More Fuel + More Air = More Power. Status: I’d rather NOT to. don’t do it. you stated that you’re not a mechanic, so it’s best to not mess with this. the stock configuration is sufficient and engineered to last a long time, when we tinker with settings it has the potential to throw that balance off. Unless you are a mechanic and do the work yourself or have lots of money to pay a good mechanic, leave the fuel and boost levels alone as stock.

6) The Turbo: More Fuel + More Air = More Power. Status: already sourced, installation planned for very soon.
the 12h-t is engineered to have a turbo charger, you need one, hopefully close to stock specs. (Wink 4x4 - Turbochargers - Wink 4x4 - Turbochargers - http://www.wink4x4.com/turbo/)

7) The Compression test. Status: Not done. I don’t have the knowledge nor the tool
it’s possible to do. Does the motor stop straight away when you turn it off? Yes, then you probably have good compression. if you had the engine rebuilt, it should have good compression.

8) The Intercooler: More Fuel + More “COLD Air” = More Power. Status: already sourced, installation planned for very soon
return it, it’s not necessary. maybe if you were going to have a bigger turbo, more fuel, bigger exhaust, etc…

9) The oil pump. Status: Replacement done with a seemingly good working one. I read that it is always a good thing to replace the old one after rebuilding the engine. I have one brand new spare Oil pump, but the mechanic managed to convince me to keep the old one as it seems still work fine. What would you advise? I’d advise to replace with a new one if it’s possible; I don’t have expert knowledge of the oil pump.

10) The Water pump. Status: Replacement done with a seemingly good working one. definitely replace the water pump

11) A 3” inch exhaust. Status: Replacement done. won’t change much without increasing boost and fuel, which isn’t necessary.

12) Gauges. Status: sourcing in progress, installation planned for very soon. oil pressure because the one in the dash probably doesn’t work, and a boost gauge

I’m definitely going to get a few of them (pre- and post-turbo, pre- and post-intercooler) what? if you’re referring to an EGT gauge, it should go preturbo in the manifold, however it’s not necessary unless you are going to increase boost and fuel and timing.

13) The brake systems. Status: sourcing in progress, installation planned for very soon. make the brakes work better, yes. I have 4runner/surf front calipers, everything else is stock. Brakes are important, recondition them to the highest level.

alright, I took a stab at your list:
1) Engine rebuilt. Status: Done.
2) The Alfin pistons. Status: Replacement Done
3) The Injection pump: Status: Replacement done with a seemingly good working one. if it isn’t broke don’t fix it. These require a high degree of expertise to repair.

4) The Injectors: Status: Replacement done with a seemingly good working ones. I don’t know much about the injectors.

5) Turning up the fuel: More Fuel + More Air = More Power. Status: I’d rather NOT to. don’t do it. you stated that you’re not a mechanic, so it’s best to not mess with this. the stock configuration is sufficient and engineered to last a long time, when we tinker with settings it has the potential to throw that balance off. Unless you are a mechanic and do the work yourself or have lots of money to pay a good mechanic, leave the fuel and boost levels alone as stock.

6) The Turbo: More Fuel + More Air = More Power. Status: already sourced, installation planned for very soon.
the 12h-t is engineered to have a turbo charger, you need one, hopefully close to stock specs. (Wink 4x4 - Turbochargers - Wink 4x4 - Turbochargers - http://www.wink4x4.com/turbo/)

7) The Compression test. Status: Not done. I don’t have the knowledge nor the tool
it’s possible to do. Does the motor stop straight away when you turn it off? Yes, then you probably have good compression. if you had the engine rebuilt, it should have good compression.

8) The Intercooler: More Fuel + More “COLD Air” = More Power. Status: already sourced, installation planned for very soon
return it, it’s not necessary. maybe if you were going to have a bigger turbo, more fuel, bigger exhaust, etc…

9) The oil pump. Status: Replacement done with a seemingly good working one. I read that it is always a good thing to replace the old one after rebuilding the engine. I have one brand new spare Oil pump, but the mechanic managed to convince me to keep the old one as it seems still work fine. What would you advise? I’d advise to replace with a new one if it’s possible; I don’t have expert knowledge of the oil pump.

10) The Water pump. Status: Replacement done with a seemingly good working one. definitely replace the water pump

11) A 3” inch exhaust. Status: Replacement done. won’t change much without increasing boost and fuel, which isn’t necessary.

12) Gauges. Status: sourcing in progress, installation planned for very soon. oil pressure because the one in the dash probably doesn’t work, and a boost gauge

I’m definitely going to get a few of them (pre- and post-turbo, pre- and post-intercooler) what? if you’re referring to an EGT gauge, it should go preturbo in the manifold, however it’s not necessary unless you are going to increase boost and fuel and timing.

13) The brake systems. Status: sourcing in progress, installation planned for very soon. make the brakes work better, yes. I have 4runner/surf front calipers, everything else is stock. Brakes are important, recondition them to the highest level.
 
That's quite the list.

When/if you add the turbo, you will need to add a Boost Compensator to the injection pump. This allows for the injection pump to dynamically change the injection volume depending on how much boost is being produced. It's an easy and cheap add-on. Maybe your old pump already has a Boost Compensator. You mentioned that you were getting a new pump, so I'm just making sure.

Read this article for a better understanding of why a Boost Compensator is needed: Basic HOW TO - Mechanical Diesel Engine Tuning Guide - https://www.tillix.com.au/mechanical-diesel-engine-tuning/

Regarding gages, you only need two. Pre-turbo EGT (installed right into the exhaust manifold outlet where it all comes together) and boost (installed right at the intake). You don't need pre/post and all that you have listed.

Congrats on getting so much done. I bet labor is really cheap over there.
Thanks for your precious precious time.
Labor tends to be cheap but sourcing the parts is crazy :)
Regards
 
That's quite the list.

When/if you add the turbo, you will need to add a Boost Compensator to the injection pump. This allows for the injection pump to dynamically change the injection volume depending on how much boost is being produced. It's an easy and cheap add-on. Maybe your old pump already has a Boost Compensator. You mentioned that you were getting a new pump, so I'm just making sure.

Read this article for a better understanding of why a Boost Compensator is needed: Basic HOW TO - Mechanical Diesel Engine Tuning Guide - https://www.tillix.com.au/mechanical-diesel-engine-tuning/

Regarding gages, you only need two. Pre-turbo EGT (installed right into the exhaust manifold outlet where it all comes together) and boost (installed right at the intake). You don't need pre/post and all that you have listed.

Congrats on getting so much done. I bet labor is really cheap over there.
Yes, labor is rather is rather cheap here... including sourcing an old 60 or 40 series... (mostly from 2 500 to 4 000 USD, though pretty hard to come across a well-preserved one ). The frienziness for classic land cruisers hasn't really got people over here.... yet :)
 
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