How is it a doomed project? Just because its not a typical low boost application? I am not trying to say compounds are 100% the way to go, I am asking for turbo advice alternative to gturbo which is what this threads for?
The 2H/12H-T/1HZ/1HD-T/1HD-FT Gturbo Alternative Tech Thread (5 Viewers)
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It's been explained several times. This will not end well. Go back and read.
You are not getting my point, I didn't come here for nay sayers to tell me my engine won't hold it. I simply want turbo advice?
Also, a factory turbo TD42 has a very similar compression ratio to a 1hz. Yes running so much boost is running more of a risk, to say it is doomed is just ignorance to other peoples ideas.
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@Joshua Thorsen I think you're getting the wrong impression here - we're not scared of 30+ PSI of boost, especially not @Dougal
Many of us here run decent boost numbers, but there are inherent design issues with a IDI diesel that don't lend themselves to high boost applications.
I don't want to appear to be a wet blanket or be bagging you out, but the block of the 1HZ (Which as you say is the same as the 1HD-T) is not the weak point - the issues keeping a high-compression engine together at high boost are...
If you're going to the effort to put a setup like this together, why not find a 1HD-T that has done a big-end or something, grab the pistons, head, injectors, fuel pump etc and turn your 1HZ into a 1HD-T?
This gives you the greater efficiency of a DI diesel, plus the advantage for your end goal of lower compression and a 12mm fuel pump which can be easily tickled to give a decent amount of fuel?
Hopefully this seems logical.
On another note, from my experience, boosted TD42s don't hold together long-term - I have a few mates with them who have been running upwards of 25lbs with reasonably aggro tunes - broken conrods etc, not pretty.
Many of us here run decent boost numbers, but there are inherent design issues with a IDI diesel that don't lend themselves to high boost applications.
I don't want to appear to be a wet blanket or be bagging you out, but the block of the 1HZ (Which as you say is the same as the 1HD-T) is not the weak point - the issues keeping a high-compression engine together at high boost are...
If you're going to the effort to put a setup like this together, why not find a 1HD-T that has done a big-end or something, grab the pistons, head, injectors, fuel pump etc and turn your 1HZ into a 1HD-T?
This gives you the greater efficiency of a DI diesel, plus the advantage for your end goal of lower compression and a 12mm fuel pump which can be easily tickled to give a decent amount of fuel?
Hopefully this seems logical.
On another note, from my experience, boosted TD42s don't hold together long-term - I have a few mates with them who have been running upwards of 25lbs with reasonably aggro tunes - broken conrods etc, not pretty.
The Factory Turbo TD42 is a much stronger engine and no-one builds them for high boost with high compression.
It's not boost we're scared of. It's helping you destroy a good engine.
If you'd like to understand peoples doubts, calculate the peak cylinder pressures at 35psi compounded boost at 4000rpm and 18:1 compression, then compare it to 35 psi boost at 22:1 compression.
22:1 compression is 22% more than 18:1cylinder.
The cylinder pressure calculation is more than I want to wrap my head around, (my head hurts just thinking about it) but I'm tipping the peak pressure increase from 18:1 up to 22:1 won't be a linear increase.
Either way, 35psi, compounded boost info a 1HZ, will at best, put 22% greater stress on head, piston, rods, crank etc than you'd see in the 1HD-T all else being equal.
What ever you do, we need YouTube!
22:1 compression is 22% more than 18:1cylinder.
The cylinder pressure calculation is more than I want to wrap my head around, (my head hurts just thinking about it) but I'm tipping the peak pressure increase from 18:1 up to 22:1 won't be a linear increase.
Either way, 35psi, compounded boost info a 1HZ, will at best, put 22% greater stress on head, piston, rods, crank etc than you'd see in the 1HD-T all else being equal.
What ever you do, we need YouTube!
What's your aim. Just to run compounds and big boost or do u have a power figure or torque curve in mind ?
For you to consider compound you must be planning to burn some rather large fuel loads. I think that will be the undoing of the 1hz more so than the boost.
If u must a 10cm would work but 12cm on the td06 would be better . 16g on the td05 6cm would be better, but not ideal.
If that all you have it will work but not ideal. Can't really give u a straight answer unless you have a clear goal in mind .
Me personally I think they drive well with a td05 18g of sorts and a 250hp pump front mount intercooler and proper intake snorkel to turbo and manifold mods .
For you to consider compound you must be planning to burn some rather large fuel loads. I think that will be the undoing of the 1hz more so than the boost.
If u must a 10cm would work but 12cm on the td06 would be better . 16g on the td05 6cm would be better, but not ideal.
If that all you have it will work but not ideal. Can't really give u a straight answer unless you have a clear goal in mind .
Me personally I think they drive well with a td05 18g of sorts and a 250hp pump front mount intercooler and proper intake snorkel to turbo and manifold mods .
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Did we suddenly transport to a parallel universe where the amazing 1HDT doesn’t exist? Why the sudden push to overwork these IDI motors?
Did we suddenly transport to a parallel universe where the amazing 1HDT doesn’t exist? Why the sudden push to overwork these IDI motors?
If you have a hard on for a td05 in a compound set up use a 14G. Dump your compression as much as you can. Deshroud the exhaust valves , get a valve grind to suck the valves into the head more will help. Retrarding timing and intercooling goes without saying. Keep in touch with your results.
Fueling will be the tricky part, I'm assuming the aim is big power 300-350hp+ getting that amount or fuel through a precomp has its challenges . Being sensible with injection timing to help with cylinder pressures may leave a shorter than ideal injection window too .
Lots of challenges with a project like this. @Joshua Thorsen Have a chat to the big name pump builders in oz, ADS injection has done a 300hp+ 1hz, might be able to give u some pointers.
Lots of challenges with a project like this. @Joshua Thorsen Have a chat to the big name pump builders in oz, ADS injection has done a 300hp+ 1hz, might be able to give u some pointers.
Of course if the aim was big power. You'd start with an engine that was better at converting fuel to power. By about 20%.
Someone has to find out the weak parts on the hz. So far I haven't really heard of a weakness, but then again no one really has done a destruction test either.
There was the guy on here a few years back who kept rebuilding his turbo (on 1HZ) only to find out the turbo was the victim of high crank-case pressure. Thread got huge but would take me a while to find it.
Apart from the head which is a well known Achilles heal.
@Dougal yeah definetly, if it were me I'd go the DI path over the Idi path, that's commonsense and good economics. I hinted at my thoughts for a 1hz. That considered the op's design brief/ request was for a compound turbo setup to suit
The 1hz..
There are 2 1hz powered cars (comp truck not daily drivers ) that I know of, both are over 300hp. All I know is they are both running gturbos and one is running an ADS injection pump. There was also a bloke on here that had a 1hz running compounds at 50psi ( z()ltan) but never mentioned a power figure. I think if you pursue/spend bulk coin on the project you'll find yourself with a 1hdt not a 1hz. After all the effort and money you put into getting the compounds on a 1hz and having it built/modified to suit compound and big power it will have been more cost effective to convert to a 1hdt.
The 1hz..
There are 2 1hz powered cars (comp truck not daily drivers ) that I know of, both are over 300hp. All I know is they are both running gturbos and one is running an ADS injection pump. There was also a bloke on here that had a 1hz running compounds at 50psi ( z()ltan) but never mentioned a power figure. I think if you pursue/spend bulk coin on the project you'll find yourself with a 1hdt not a 1hz. After all the effort and money you put into getting the compounds on a 1hz and having it built/modified to suit compound and big power it will have been more cost effective to convert to a 1hdt.
The head is an IDI weakness in general, not necessarily power related. Well it wil be interesting to see what happens.
Hey not massive power, definitely above 250+ mark though. It’s more the fact that my td06 -20g has done pretty much no work and my hate has the 18g with small 6cm rear so I thought run the same boost but make it more responsive with the compound setup and still have the top end flow.
Converting it to a 1hdt is more work and expense and easier said than done when it’s not you funding the project. If I had my time over again I would get a hdt but I’m not trying to make 300 + hp.
I already have a good 12mm and not trying to run a massive soot monster.
I appreciate the input. I’ll be most likely getting a 12cm v band rear housing for the td06. I’ll start with that and if it’s not responsive enough will change the front wheel and housing on the td05.
My other reason I’m considering compound is the turbos will be working in a more efficient range.
