The 2H/12H-T/1HZ/1HD-T/1HD-FT Gturbo Alternative Tech Thread

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Aug 16, 2013
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Qld, Australia
 
The dyno charts, are they the same car, did you change turbos and diff ratios? The extra load from 3.7’s over 4.1’s will make the pump behave a little differently

I am surprised fuel efficiency isn’t sacrificed with the high rpm turbo .

What are you doing with injection timing advance when running peak power at 4000rpm +. Re piston speed this is very relevant I wouldn’t be ignoring this .

I think if you were aiming for higher hp say 250hp+ you would definitely see fuel economy decrease with majority 3000rpm+ driving compared to a setup that does the same power but delivers most of it below 3000rpm

Myself I prefer a turbo that’s matched to lower rpm peak torque for a daily driver

Always interesting to see different peoples approach to achieving their version of perfection .
 
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I am surprised fuel efficiency isn’t sacrificed with the high rpm turbo
There are very few people who track fuel economy well enough to determine the result of any change. I log every tank and I have seen 10% change in fuel economy from a turbo change. But that was more due to compressor efficiency than the turbo size. Even though the turbine and compressor size changed too.
 
Joined
Aug 16, 2013
Messages
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Location
Qld, Australia
 
There are very few people who track fuel economy well enough to determine the result of any change. I log every tank and I have seen 10% change in fuel economy from a turbo change. But that was more due to compressor efficiency than the turbo size. Even though the turbine and compressor size changed too.
I do too . Something i picked up from My dad. Even though my driving isn’t even close to a controlled environment I can get a Good idea of average economy.
 
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Mar 11, 2019
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80 Series 1HD-FT
The dyno charts, are they the same car, did you change turbos and diff ratios? The extra load from 3.7’s over 4.1’s will make the pump behave a little differently

I am surprised fuel efficiency isn’t sacrificed with the high rpm turbo .

What are you doing with injection timing advance when running peak power at 4000rpm +. Re piston speed this is very relevant I wouldn’t be ignoring this .
Yes, those two dynos are the same car. I changed the turbo and diff ratio at same time due to damaged cause from a drunk driver deciding to crash head on into it. Pretty much the whole front end was replaced so I took the opportunity to change the ratio in the diff while it was being rebuilt. Engine luckily wasn't damaged.

I was surprised too but it's not something I really keep track of or really care too much about as it's not my daily. I reset my trip meter each time I fill up so the total km I get for each tank is all I really remember or notice. I just fill it up and enjoy the drive.

I haven't touched the timing yet with this new turbo, still running the same injection timing as before. The timing was set previously by doing time trails using a couple gps/speed apps in fourth gear from 40kph to the speed I made peak boost and the position that set the quickest time was kept. It seems to go well with this turbo down low also and still holds on very well up top but I plan to retest the timing as before but I can't risk randomly driving around at the moment with all this lock down and essential movements only that's going on
 
Joined
Aug 16, 2013
Messages
186
Location
Qld, Australia
 
Yes, those two dynos are the same car. I changed the turbo and diff ratio at same time due to damaged cause from a drunk driver deciding to crash head on into it. Pretty much the whole front end was replaced so I took the opportunity to change the ratio in the diff while it was being rebuilt. Engine luckily wasn't damaged.

I was surprised too but it's not something I really keep track of or really care too much about as it's not my daily. I reset my trip meter each time I fill up so the total km I get for each tank is all I really remember or notice. I just fill it up and enjoy the drive.

I haven't touched the timing yet with this new turbo, still running the same injection timing as before. The timing was set previously by doing time trails using a couple gps/speed apps in fourth gear from 40kph to the speed I made peak boost and the position that set the quickest time was kept. It seems to go well with this turbo down low also and still holds on very well up top but I plan to retest the timing as before but I can't risk randomly driving around at the moment with all this lock down and essential movements only that's going on
Copy, how do the timed runs compare between setups ? Not really a fair comparison but interesting to know still.
With timing I was referring to the timing advance mechanism in the pump, was wondering if you had it mapped to complement the turbo and higher rpm power band .
 
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Mar 11, 2019
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80 Series 1HD-FT
Lol slower obviously but to be fair going from 4.1 to 3.7 ratio diffs is quite a big jump so I kinda need to start all over again with my times for fourth gear pulls. But the longer legs it now has being able to hold third till 120kph and fourth till 180kph suits much nicer. Just a shame I can't give it a real test as all the diesel assaults have been cancelled for the unforseen future. It's ok though always plenty of other stuff to focus on like getting my water/meth system fixed up.

As of yet nothing changed in the auto advance piston but I've been in contact with a company making spacers to give it slightly more range of movement which looks interesting to try but I need to see how the extra RPM goes first and at what stage this becomes a factory causing power to plateau. I'm sure there's a point it'll need to be looked into but currently power is still increasing at a good rate at 4200 so I'm hoping it'll continue to 4800 which I think might be enough for me to be happy.
 
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