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

[KiwiDingo]

@KiwiDingo
Are you still running the eclipse turbo ?

Nope not for now, I wanted to do a little project of designing my own turbo to see how little boost I could use to get 200hp with no cooler. Only showed 195hp on this run but it makes 200. They guys doing the dyno didn't realise my turbo setup was designed to make peak power at max RPM and they kept stopping the run just after 3000 like they normally do with normal setups (I don't like normal haha), each run they did I could see the Nm/hp drop slightly each time as the sealed dyno booth was becoming a sauna . It took awhile for me to convince them to stop pussy footing around and rev it out. Even then they still only got to 4000 on the 13th back to back run as they slowly increased RPM each time but it easily goes past 4200 while still building power. I think they thought I'd blame them if something went wrong which is understandable I guess, annoying but understandable.

For comparison to the Eclipse I was running previously, according to the dyno which is a different dyno, I've lost a bit early on and peak power is at different rpm which I purposely designed that way. I'm a big believer in using the full engine RPM and having a turbo designed to still allow me to have a rising power curve at max RPM is key to this, otherwise you keep needing to change gears early to continue accelerating. Plus making 200hp at 4000 is a lot safer on the engine in terms of peak cylinder pressures than making it at 3000.

Eclipse turbo - 150kw-200hp/555Nm @24psi, PDI front mount cooler, 4.1 ratio diffs, max EGT on test hill 750 degrees C
- EMP during spool and at peak boost 1.3:1, at max RPM 1.6:1
Custom CT26 - 145kw-195hp/480Nm @13psi, No cooler, 3.7 ratio diffs, max EGT on test hill 600 degrees C
- EMP during spool and at peak boost 0.7:1, at max RPM 0.9:1

Also don't let this low boost really tame 200hp tune fool you, this turbo can easily hit 22psi before 2000RPM! This was just purely a project of mine and a bit of a competition I had with mates about who can make 200hp with the lowest boost. So much for 9 blade turbines being only good for ricers

 

[mudgudgeon]

a big believer in using the full engine RPM and having a turbo designed to still allow me to have a rising power curve at max RPM is key to this, otherwise you keep needing to change gears early to continue accelerating. Plus making 200hp at 4000 is a lot safer on the engine in terms of peak cylinder pressures than making it at 3000.

Bollocks

 

[KiwiDingo]

Bollocks

Which part disagrees with you?

 

[Indestructible 47]

Which part disagrees with you?

For a start, nobody should be reving a 1hdt to 4000rpm. Second, no matter how good a turbo you put on it, or whatever your setup is, a diesel motor makes max torque low in the rev range. Third, rev a 1hd, 1hz above 3000rpm for long and you will end up with oil in the intake. It's a known issue. If I'm missing something, please feel free to call me out.

 

[KiwiDingo]

For a start, nobody should be reving a 1hdt to 4000rpm. Second, no matter how good a turbo you put on it, or whatever your setup is, a diesel motor makes max torque low in the rev range. Third, rev a 1hd, 1hz above 3000rpm for long and you will end up with oil in the intake. It's a known issue. If I'm missing something, please feel free to call me out.

Mines a FT and is factory limited to 4400rpm and Toyota would not have let me rev it that high if it was an issue. Not sure about DT's as I've never owned one but I think they're only 4200rpm? Yes I know they make torque low down, I was referring to hp and cylinder pressures though so not sure what your question is? What's the oil in the intake issue, I've never heard of this or experienced it on my HZ or FT engine. My engine lives most it's life above 3000rpm as well so that's very strange.

 

[AussieHJCruza]

I wasn't going to participate in this, but I think max power at 4k+ is a bit pointless.

As Grahame said to me, just because you can doesn't mean you should. With a 3" exhaust, my 1HDT made max torque at about 1800 and power at 3600. With an intercooler and tune, same thing. Red wheel at 20 psi and factory intake, pump and injectors, same thing. 4" snorkel, moonlight airbox, worked 12mm pump timed at 1.3mm lift, injectors and 25 psi, 1800 and 3600.

I realise you have an FT and therefore it probably carries decent VE higher in the rpm range, but I really doubt it's at optimal efficiency anywhere above 4k.

I had a GU patrol with a cammed and tuned LS2. Torque was 4k, 220 rwkw on 35s at about 6k. Fun at the traffic light drags but useless for basically anything else.

My point is, obsession with one particular factor, be it boost, EMP, AFR or whatever doesn't tell the whole story. I would be fairly confident saying that my HDJ80 with a couple of tonnes behind it, max torque as low as possible without bending rods, thrashing the big-ends or whatever and max power at 3600 wouldn't be much slower if at all than said LS2, and certainly a lot more pleasant to drive rather than have to row the gears to keep it on the boil, thats acceptable in a WRX but not a cruiser.

I want a diesel truck to be torquey and pull like a freight train, not to rev to the moon and back. If that means higher EMP or a bit lower max power, so be it...

 

[KiwiDingo]

Everyone uses there vehicles differently and one perfect setup for one is absolutely terrible for another. I've been saying this the whole time, each setup needs to suit the performance goals and driving style of the driver. I've never loved driving mine more then I do know so that tells me all I need to know

 

[AussieHJCruza]

Everyone uses there vehicles differently and one perfect setup for one is absolutely terrible for another. I've been saying this the whole time, each setup needs to suit the performance goals and driving style of the driver. I've never loved driving mine more then I do know so that tells me all I need to know

Certainly agree with this and hey, if you're happy, that's all that really matters - your truck, modify accordingly.

 

[mudgudgeon]

Which part disagrees with you?

All of it.

I'm a big believer in using the full engine RPM and having a turbo designed to still allow me to have a rising power curve at max RPM is key to this,

maximum power is always going to be lower than maximum rpm as volumetric efficiency drops off towards the top end. Revving beyond peak power is pointless most of the time.
For a 1HDT max power is at about 3600 rpm hdft is similar, I can't remember exactly. Beyond that vokumetric efficient and power drop away. Adding a turbo doesn't change the physical properties of the engine. This is governed by camshaft lift and duration, port shape, intake runner length, shape etc, none of which changes with a turbo. A turbo can overcome it to a certain degree, but you face diminishing returns.

QUOTE="KiwiDingo, post: 13026522, member: 151764"]
otherwise you keep needing to change gears early to continue accelerating.
[/QUOTE]
Acceleration is strongest from peak torque. In a diesel peak torque is at low RPM, 1hdt in standard spec peak torque is at 1800RPM.
This is where a turbo has greatest effect in overcoming volumetric in efficiencies.

Another factor here is the spread between gear ratios. With a manual trans, there's about a 12-1500 RPM split between gears. Upshifting you want to change gears so your engine speed is close to peak torque as you shift into the higher gear.
An upshift at 3500rpm will land you at about 2200rpm ish. Change gears at 4400, rpm drops to 30-3200ish rpm. You're leaving all the torque available below this unused.
Either way, you only use 1500ish revs somewhere on the rev range.

Redline is a safe upper limit for RPM, not a target.

Forces generated by the piston accelerating and decelerating up and down in the bore increase hugely as engine speed goes up.
Forces on pistons, conrods, rod bolts, bearings, wrist pins etc goes through the roof.
Increase in force is equal to the increase in engine speed squared. Increase engine speed by 2 times, the forces generated are quadrupled.
Increase engine speed from 1000 to 2000 rpm, force increases by four times.
From 1000 to 3000, force increases by 9 times
From 1000 to 4000, force increases to 16 times. That last 1000 rpm has doubled the load and strain on critical components.

No engine designer is going to suggest you run at the upper end of the rev range as a normal practice.

The more time an engine spends close to redline, the shorter it's serviceable life will be. Rod bolts etc can be stretched only do many times before they fail. Increase the forces and increase the frequency by running at high RPM you down their life

 

[mudgudgeon]

Everyone uses there vehicles differently and one perfect setup for one is absolutely terrible for another.

Within reason, sure.

You can't change the laws of physics just because you like to rev the shìt out of your truck.

I say that as someone who is happy to push an engine to redline in the extremely rare situations where is actually warranted

 

[mudgudgeon]

my 1HDT made max torque at about 1800 and power at 3600.

Hd-ft is very similar, maybe 100rpm difference from memory

 

[KiwiDingo]

All of it.


maximum power is always going to be lower than maximum rpm as volumetric efficiency drops off towards the top end. Revving beyond peak power is pointless most of the time.
For a 1HDT max power is at about 3600 rpm hdft is similar, I can't remember exactly. Beyond that vokumetric efficient and power drop away. Adding a turbo doesn't change the physical properties of the engine. This is governed by camshaft lift and duration, port shape, intake runner length, shape etc, none of which changes with a turbo. A turbo can overcome it to a certain degree, but you face diminishing returns.

Acceleration is strongest from peak torque. In a diesel peak torque is at low RPM, 1hdt in standard spec peak torque is at 1800RPM.
This is where a turbo has greatest effect in overcoming volumetric in efficiencies.

Another factor here is the spread between gear ratios. With a manual trans, there's about a 12-1500 RPM split between gears. Upshifting you want to change gears so your engine speed is close to peak torque as you shift into the higher gear.
An upshift at 3500rpm will land you at about 2200rpm ish. Change gears at 4400, rpm drops to 30-3200ish rpm. You're leaving all the torque available below this unused.
Either way, you only use 1500ish revs somewhere on the rev range.

Redline is a safe upper limit for RPM, not a target.

Forces generated by the piston accelerating and decelerating up and down in the bore increase hugely as engine speed goes up.
Forces on pistons, conrods, rod bolts, bearings, wrist pins etc goes through the roof.
Increase in force is equal to the increase in engine speed squared. Increase engine speed by 2 times, the forces generated are quadrupled.
Increase engine speed from 1000 to 2000 rpm, force increases by four times.
From 1000 to 3000, force increases by 9 times
From 1000 to 4000, force increases to 16 times. That last 1000 rpm has doubled the load and strain on critical components.

No engine designer is going to suggest you run at the upper end of the rev range as a normal practice.

The more time an engine spends close to redline, the shorter it's serviceable life will be. Rod bolts etc can be stretched only do many times before they fail. Increase the forces and increase the frequency by running at high RPM you down their life

Bollocks

Max power can very easily be made at max RPM or any other RPM for that matter with changes to setup combinations, it isn't a fixed outcome. Volumetric efficiency can be affected and changed also by setup.

Cool story about the gear changes, don't really care. I just change gears when the power starts to level out before it falls away. It's very easy to tell this point while driving with turbos built to perform better at lower RPM as you no longer continue to accelerate at the same rate, although you'll still continue to build speed it'll be much quicker to shift.

Safe upper limit for one is the target for another. Like I said not everyone wants the same from their setups.

Yes, I completely agree with you about those specific forces you mentioned. Not sure why you did though because all I was referring to was cylinder pressure and the effect on it by making the same HP at different RPM. Peak cylinder pressure will be much higher at 3000rpm making 200hp compared to at 4000rpm making the same. Simple math, I'll let you work that out since you seem to enjoy it.

Meh, not fussed too much about service life. Just gives me another project to work on or maybe another engine conversion to try. Like I said, not everyone wants the same things.

 

[KiwiDingo]

Within reason, sure.

You can't change the laws of physics just because you like to rev the shìt out of your truck.

I say that as someone who is happy to push an engine to redline in the extremely rare situations where is actually warranted

What laws of physics am I apparently changing?

Also one man's definition of "rev the s*** out of your truck" is another's safe and useful range.

 

[KiwiDingo]

Hd-ft is very similar, maybe 100rpm difference from memory

This can really easily be changed with setups. Example when I had my Gturbo grunter my Max torque was 1600rpm and peak power 3000rpm. Again this isn't a fixed outcome as it's all dependant on everyone's setups

 

[Dougal]

In case anyone is wondering what limits the max usable rpm of a diesel. It's the burn speed of diesel. Which matters in relation to piston speed.

A 2.0 VW TDi makes max power at 4000rpm. Max piston speed is 20 m/s at that 4000rpm.

Take that same 20 m/s and apply it to a 118mm stroke 4BD1T. You get 3230rpm. Which is exactly where Isuzu had it making peak power.

Apply 20 m/s to a 1H engine (100mm stroke) and you get 3900rpm.
The fact Toyota had it making max power a few hundred rpm lower suggests they were either battling dropping VE or were extending engine life.
Try to make power at higher rpm. Wasting your time. If you pull the same boost and fuel to a few hundred rpm sooner you'll make more power.

 

[mudgudgeon]

This can really easily be changed with setups. Example when I had my Gturbo grunter my Max torque was 1600rpm and peak power 3000rpm. Again this isn't a fixed outcome as it's all dependant on everyone's setups

By adding a turbo that works outside the engine's most efficient range is not changing the physical limits of the engine.
No doubt orce feeding in more fuel and air to compensate for working the engine outside is design parameters can see an increase over stock power, but it comes at a cost.

More fuel burnt, greater heat loads, greater strain on the engine, reduced engine life.

It's a bit like using a sledge hammer to squash a fly, sure it works, but it's not the most elegant way to do it.

Hey, it's your cat, you can fxck it however you like

 

[KiwiDingo]

Try to make power at higher rpm. Wasting your time.

Maybe considered a waste of time by you but not me. Time well spent I say, in fact I know of others myself included embarking on increasing the rpm range even further. I'm taking mine in slow steps with 4800rpm being the next level but I already know others who have gone well beyond this and the results have been exceptional. Like I keep saying there's no right or wrong, everyone uses there vehicles differently.

 

[KiwiDingo]

Dang! That's a brain bending set of headers

Keep the pics coming

I reckon we are going to need lots of pics

Hmmm interesting change of tune you have going on there @mudgudgeon, you were loving the crazy high hp 1HD builds I was posting a while ago which all make there peak HP at very high RPM (most likely at very max RPM) but now you're carrying like a pork chop over me wanting to pursue my own goals of desired engine performance. Once again it seem like the usual case of death by fire squad around here from the usual suspects for anyone sharing thoughts or opinions of their own setups or ways of doing things that differ from the square box they live in.

 

[AussieHJCruza]

I suppose it's a matter of personal preference, but in my opinion the appeal of a worked diesel is brutal low end torque. That can't be done without a turbo that spools stupid fast and a good tune.

As Carrol Shelby said, horsepower sells cars, torque wins races. Yes, I realise an 80 isn't exactly made for drag racing but who cares...if I wanted an engine to rev, it would be a 13B Bridgeport...shift gears at 10k...

 

[Dougal]

I suppose it's a matter of personal preference, but in my opinion the appeal of a worked diesel is brutal low end torque. That can't be done without a turbo that spools stupid fast and a good tune.

As Carrol Shelby said, horsepower sells cars, torque wins races. Yes, I realise an 80 isn't exactly made for drag racing but who cares...if I wanted an engine to rev, it would be a 13B Bridgeport...shift gears at 10k...

Not only that. But the fuel economy benefits of a diesel come at low rpm. Make them scream for their living and your fuel economy turns to garbage.

There can be 30% difference in fuel economy between 200hp delivered at 2000rpm vs 3500rpm.