Factory 1HZT (1 Viewer)

[DamoPeru]

well i may as well just post up a heap of photos once and for all, my only turbo experience is the 1HZ AXT I had on so I'm new to CT26's and anything you can tell me will be much appreciated. let me know if you want any measurements. I might peel back the paper seals if it comes to that. Anyway here's all the stamped or stickered codes it has and a few other general shots.

 

[ForealBoreal]

That turbo is crossing over with the 14B-T, 13B-T and 12H-T engines.
So its a early 1hd-t turbo. Smaller compressor wheel than the supra and running the same turbine. The later models the compressor wheel gets bigger (supra size) then the housing/turbine wheel gets smaller.
There isn't a whole ton of variations with these turbos from my research.
A few little tweaks/combinations really. All really interchangeable in the scheme of things.

 

[ForealBoreal]

obviously speaking that the smaller turbine/housing with the bigger comp wheel is the more recent design called the CT15b.
Which is still interchangeable with the CT26 parts. CT15b for example came on the 1hd-fte cruisers.
If you were to swap that out with a supra comp housing it would work just fine and preform better that that turbo in terms of higher boost pressures and earlier boost.

 

[DamoPeru]

I'm going to run it stock for a good while I reckon, that's the only reason I forked out the ridiculous price for what it is. I think it will be kinda cool to have a stock 1HZ-T and well for my touring purposes it's probably the best way to go. I am annoyed I got the aftermarket pistons now, after they all told me the OEM 1hz-t pistons couldn't be had, a little bird tells me he should be able to get them.

 

[ForealBoreal]

Relax the Alfin inserts are worth it.
I am going to be providing upgrade kits for the CT26 turbo shortly.
Hi-Flow units at a cheaper rate and just as good quality if not better.

 

[crushers]

obviously speaking that the smaller turbine/housing with the bigger comp wheel is the more recent design called the CT15b.
Which is still interchangeable with the CT26 parts. CT15b for example came on the 1hd-fte cruisers.
If you were to swap that out with a supra comp housing it would work just fine and preform better that that turbo in terms of higher boost pressures and earlier boost.

that would depend on driving style and application.
the 1HZ as is pulls fine but if he has high long hills at highway speeds then this turbo will work good for him.
if he was after city driving where early boost is needed then your suggestion makes total sense.

 

[ForealBoreal]

the combination I am running which is all CT26/Ct15B hybrid will hold 18lbs to 3600k rpm if you want it to.

 

[DamoPeru]

Relax the Alfin inserts are worth it.
I am going to be providing upgrade kits for the CT26 turbo shortly.
Hi-Flow units at a cheaper rate and just as good quality if not better.

Yeah I'm not worried that they'll fail early, but I would have preferred a 100% OEM 1hz-t regardless of whether the pistons are capable of lesser performance, as I need reliability over performance. I just want better hill performance and a bit of extra grunt for dune and beach driving in what will be a loaded 3.6t home on wheels.

 

[ForealBoreal]

They should be just as reliable.
Did you deal with precision or engines Australia?
I wouldn't bat an eye with these being any less reliable than OEM.
Heck solely for the reason of your running a turbo its better than stock.

So you want more grunt and hill performance. Boost and fuel to suit.
Boost won't kill your engine, low AFRs and High EGTS will.
Remember that running 8 or 10lbs with 18:1 AFR is less reliable vs 15lbs and 22:1 AFR.
Don't be scared to suit, not to mention there is a ton of DIY info how to tune your boost comp.

 

[DamoPeru]

I was playing and tuning on my second rebuild with some good results but my goal for this third rebuild is to baseline the performance of an 1hz-t as close to OEM as possible in a LC, and i made a conscious decision between sticking to specs with the 1hz-t turbo and going for a gturbo to increase performance, the latter actually would have been cheaper. I plan to tune the 10mm 1hz-t pump as close to 10 mm 1hz-t specs as possible (I still haven't decided if I'll remove the 1hd-t boost comp briefly just to be anal and get those true baseline figures), leave the turbo spooling to the boost intended (I assume the wastegaste comes from the factory at that setting), and if it works for me I'll leave it at that. Unfortunately I no longer have my old stock exhaust for the initial baseline, just the 3" straight through. Later I'll put the FMIC back on and see what happens before deciding if it stays on and then maybe do some performance tuning if i think i need it, but I want to stick with OEM design components and keep her tuned to run really cool.

I was just doing another crosscheck of the EPC, and according to the range of part numbers, I just realized that couldn't have used the OEM 1hz-t pistons (13103-17030) anyway, as my 1hz-t is of 2002 vintage with the newer head, crankshaft and piston top design etc., so it seems the engine australia pistons are still the best option i had... i forgot all about that post 99 1hz issue.

however for all you guys in the states about to import JPN 24V 1990 HZJ7# that like restoring to OEM specs, a complete changeout with 1HZ-T parts would be a very cool and unique project hopefully crushers gets to do it soon... still another 11 years until you can get a HDJ7#.

 

[ForealBoreal]

you have options turbo wise. There is some stuff coming down the pipe that can make this more realistic for people. Wait and see.
You would be crazy to rip the boost comp off your pump. It will make your truck much cleaner to drive not to mention less harsh if your not at full boost.Keep the bloody thing trust me, its in your best interest.

 

[Ptrott]

 

[DamoPeru]

you have options turbo wise. There is some stuff coming down the pipe that can make this more realistic for people. Wait and see.
You would be crazy to rip the boost comp off your pump. It will make your truck much cleaner to drive not to mention less harsh if your not at full boost.Keep the bloody thing trust me, its in your best interest.

Yeah sorry maybe I wasn't clear enough, I wouldn't dream of running it without the boost comp, I am just thinking about doing a first dyno run without it to get a baseline. I imagine about 5 or 6 dyno runs: before and after putting back on the boost compensator, then exhaust wrap, then intercooler and then with some different tunes until I get it to where it will stay, all purely for the sake of knowing.

 

[crushers]

i look forward to your results ...
Yan and I are chatting about doing a factory HZ-T build and a Mapped turbo - stock 1HZ internals build to compare the results (in a pair of 40 series) in the way of fuel economy, performance, temps and (if we keep the trucks long enough) longevity.
For me, it would be interesting side by side comparison ...

 

[DamoPeru]

That comparison will be very interesting and ultimately the only way to shed a bit more light on this thing... it's not everyday you get to test an OEM toyota motor previously unknown to the toyota community. I hope you get to do it.

My data will be useful to me, but not that useful to the community as I don't have dyno runs from when it was a stock standard 1hz. I'm about to travel so I won't be starting the rebuild until late february/march.

 

[crushers]

the factory HZ-T will be determined by Yan's budget.
I have done a number of the mapped turbo stock HZ engines and have been very happy with the results. I map them for highway use. there is very little boost off line but when that bugger starts to pull .... damn ... i get a grin every time.
I will work on Yan, I too would love to see a factory one perform.
can you picture 2 40s running side by side with that kind of kick in the pants?

 

[maat]

Still nothing from rosco

 

[DanS HJ-45]

This thread never ceases to fascinate me.

I'm rebuilding an IP now for a 1HZ that will get a turbo. Since I am rebuilding it either way, I have a choice:

Rebuild the IP stock
Rebuild the IP with the specs of the 1HZ-T
Rebuild the IP with specs of 1HZ-T and boost compensator

I'm leaning towards the last, but I'm open to suggestions. Thoughts?

I'm not looking for beauceap power, I'd rather that the engine run as cool as possible up long steep hills, and of course last a long time.

Dan

 

[ForealBoreal]

What are your power goals?
Get a boost comp regardless....

 

[DanS HJ-45]

What are your power goals?
Get a boost comp regardless....

Define goal?

If it's about like the 12HT is, then I'd be very happy.

I'm not looking to make it into a monster hot rod, just have decent power (to push a 60) up 4% grades at, say 55mph without having to worry about it overheating. That's more important to me than power.

I've got a boost compensator, so that narrows it to two choices:

• stock 1HZ pump with boost compensator
• 1HZ-T pump with boost compensator

The diesel shop thinks they can build it to the 1HZ-T specs, which is why I'm asking. If they hadn't said anything I suspect I would have been plenty happy with a rebuilt IP with a boost compensator on it.

Dan