Help with power increase 1HD-T

[DaveHDJ80]

Hi,

Have an 80 series with 1HD-T mated with 5 speed. 270k on the clock - motor seems in good nick. Have just replaced big end bearings.

Wanting to know about power increase with fuel/boost and am new to diesel engines.

What I am looking for is getting the most out of the engine, without decreasing engine life or economy. If this is not possible just let me know and I wont worry about it.

Only engine mod is a beau exhaust 3 inch mandrel job with straight through muffler. Injector pump has been rebuilt about 120k ago to suit the sulphur change n fuel i think. Done before i got it. Apparently set to standard specs.

BOOST - I understand that the 1HDT has a compensator that will adjust fuel to suit boost level to an extent - off throttle/idle etc. What are the limits of this compensator? That is, can boost be increased much or at all without playing with fuel?

If power increase is possible without losing much economy, what are realistic boost levels?

I am going to fit an ENG-TEK pyro meter to monitor things prior to any changes. What are acceptable EGT (after turbo) for a 1HDT motor? What would you set it at for alarm on/off?

Not looking to intercool at this stage, but something I would look at down the track with a front mounted job.

Thanks for the help

Dave

[ledgend80]

hi dave

post turbo temps about 550 max

pump adjustments will help as well as the 3 inch exhaust that you have

get your turbo high flowed or replace the ct26 with a garrett
gt2860 or gt2871r or gt2876r plenty of threads on here about turbos

intercooler will help the engine in the long run as well as allowing you to run more fuel and boost

but it all comes back to how much you want to spend or how much you can afford

[80's_delirious]

You can get some big increases in output, depending on how it is currently tuned.

Turning up boost alone is not the full answer. If it's not already gettin more fuel than it needs, then more boost wont create more power.

More boost, plus more fuel is what is needed. However increasing fuel too much can be a problem if not done carefully. Too much fuel in a diesel engine creates excess combustion heat (the opposite of a petrol).
From my own experience tinkering with mine I would strongly recomend the EGT guage, it gives the best indication of how close to the wire you have things tuned. It is scary how quickly temps can rise if you tune it too rich. I would put the probe in the manifold before the turbo, its generally regarded as more accurate. Before turbo 650-700 oC to be safe 750-800 oC peak if you dont mind a gamble.

THe 3" exhaust is ideal, an intercooler will give more scope to increase fuel plus boost safely.

the pump is designed to limit fuel delivery once boost exceeds ~15psi, and the stock turbo is getting suspect beyond around 15psi too (I blew a turbo running it at too high boost)

have a read here http://www.lcool.org/technical/80_serie ... p_adj.html
There is a fair bit of adjustment in the boost compensator and fuel settings, it gets tricky and fiddly if doing it yourself.

this is the same for 1HD-T and 1HD-FT.


try and search the Toyota section here, its been discussed a few times now.

Good luck

[DaveHDJ80]

Thanks for the thoughtful replies - much appreciated.

I'm starting right from scratch with diesel motors. Experienced in building hot triple carbed holden sixes - but doesnt count for much here! In any case, I guess I understand the fundamentals but i guess the boost factor makes the cam profile and head flow a bit redundent in this new scenario!


I will do some searches and make some notes then put up so Qs.

In terms of the probe for EGT, a mate told me that pre-turbo was more accurate but might be nasty in the case that the probe breaks and goes through the turbo...

The dump pipe has an existing 1/4 BSP fitting so i think I will use this to begin with at least.

As far as I am aware, my setting for boost and fuel are standard factory. Having said that, it seems to go very well - much better than a mates turbo 1HZ that intercooled and running about 11-12psi boost. Could just be the direct injection i guess - hard to say I dont have another vehicle to compare it to.

Maybe i just think its a rocket compared to the old 60 3F!

Thanks for the help.

Dave

[DaveHDJ80]

The three tweaks listed on LCOOL sound sensible and a good starting point.

My engine does not seem to have an issue with off idle response as listed in the LCOOL acticle.

I live in cloncurry, but will be in brisbane at xmas. Can anyone recommend a workshop that could look at the existing settings and make the tweaks without just reaching for the main adjustment? At the same time I would like to get my injectors tested as it is 130k since last injector service.

I think I will start with that, and then monitor EGT over various trips and then move towards a front mount intercooler.

Safari seem to be well recommended - any otheres worth considering?

[mick80]

give peter a call at redlands 4wd centre capalaba he seems pretty genuine.
cheers mick

[CustomTurbos]

My preference would be to stay with the CT26. 20psi has been no problem in my experience (and that included towing a caravan up to Threadbo) so long as you have an upgraded compressor wheel and auto. If manual, safer install a 360deg thrust washer and you can run even to 30psi.

My 1HDT Auto rig was dynoed at United Injection in Perth at 114kw @ all 4 wheels (33" tyres, dynoed in 3rd with lockup). Peak torque was ~ 2000rpm but I could get good boost (10psi) by 1400rpm. I ran wastegate closed and often went to 25psi. I dont reccomend that. In hindsight I should have set boost to ~ 20psi and I probbaly would have picked up some kw. It drove very well and returned excellent economy.

I did the high flow myself using a Mitsubishi compressor wheel. The turbo response was excellent and the performance was similar to my LX470 in acceleration but up a grade the 1HDT was better because the torque spread was just sensational - would always pull up to 2200rpm in any gear on the TC before lockup. I could pull a 2 tonne caravan with car fully loaded with full size roof rack, Wife (small) and three kids in 4th up most mild hills, 3rd locked up when doing above 70km/h up just about anything. I was always very dissapointed when it couldnt pull top :-). There is a long steep hill on the Hwy from Townsvill to Cairns (as I recall) and I was still in 3rd at the top, but dropped to 3rd @ 70km/h ~ 1700-1800rpm.

Other mods were eBay typical 600*300*75 intercooler and 3" exhaust. I had EGT (pre turbo), EMP and IMP gauges. Seldom saw more than 600deg C and never more than 670. this was under sustained power runs.

EMP was ~ 40psi to get 25psi inlet pressure at say ~ 3000rpm. But at 1800rpm EMP was ~ 29psi for 25psi IMP.

My rig wasnt maybe at the power you are looking for, but the pump was stock std. I tweaked the main fuel screw and aneroid profile (put in a stiffer spring too) to best suit the turbo. I was very happy with the performance. A friend with a chipped 100 series thought mine had more torque and better bottom end response, but his was better up top. The dyno said the same thing.

I cant be conclusive on what would be better power wise or why I wasnt getting the power I thought I should be up top (Was hoping for over 150kw @ wheels) but since the EMP to IMP appeared favourable, it must have been things like pump timing, inlet air temps (never measured them).

The CT26 has a turbine ~ GT30 in size. I have tried a clipped turbine with std comp wheel on a 12HT Auto just for fun and ran it to ~ 20psi without intercooler. It put down 133hp @ wheels and low rpm boost seemed similar (I thought it would suffer alot). 1/4 mile in under 19 seconds I did post a youtube vid of it. Suprisingly it didnt blow much smoke either. I mention this just to say there are options that you can go for, cheaply without having to change oil lines, water lines and other plumbing that "just bolts up".

I am installing a 1HDFTE in my LX470 now (there is a thread started, but in infancy) and will install a high flowed CT26 (after dynoing with chip, big intercooler and exhaust the factory CT20B) and will dyno back to back. A few months off doing that though. A stock 1HDFTE Turbo from July 2002 onwards is very similar specs (hot and cold ends) to a plain bearing version of a GT2860RS so it has a smaller turbine than the CT26 (48mm exducer vs 52mm = 17% smaller!). That is why a post 2002/07 1HDFTE 100 dynoes so much better from 1400rpm and up. As I understand it, the earlier 100 had the CT26 and made the same peak HP but did hold it a few undred rpm higher in the rev range before dropping off. So, for a stock setup, the 100 series turbo is a very nice option - might bolt up to a CT26 pattern too - I dont know since mine hasnt been taken off yet. Could be something to consider. FTE's have made 600nm (610nm max I heard) on the stock turbo. A 1HDT or 1HDFT should get close to that.