12H-T boost mods

[kevin in okinawa]

i am a cheerleader for the water/meth injection.

whereas rolling down the road or highway a traditional air/air intercooler works great at dropping charge temps, when you are crawling through a jungle trail you don't get much air forced thru the fins of the intercooler...pretty much negating the advantage when you need it.

the water/meth injection setup works when you need it to work...and you can usually customize when the thing comes on depending on boost or egt levels.

i learned about this stuff from the old turbo Buick Regal and Grand National crowd.

here are two sites:

Snow Performance: Stage 1 Diesel Boost Cooler?

Water Injection, Methanol Injection, Alcohol Injection Systems | Coolingmist

 

[crushers]

this has always puzzled me...
when you are 'crawling' through the bush you are producing no sustantial turbo boost, it is the turbo boost that creats the heat that the intercooler removes. if there is no heat then what is the need for an intercooler or water injection?
water injection is usless at crawling speeds, as is an intercooler, propane injection or even a trubo for that matter. it is when loading up that all these units come into play.
if the turbo is loading up then the speed is enough to move air over, through the intercooler.

cheers M8s

 

[kevin in okinawa]

when i say "crawling" it was a somewhat figurative use.

i meant more like: clawing your way back up the hill, etc...

there are PLENTY of times on the trail when the turbo is going to be spooling and working hard to generate more power to get through that particular section...and your speed, and respective access to air flowing thru an intercooler, is going to be negligible.

the water injection is effective when the engine is being worked hard, regardless of the environment or circumstances.

a denser charge in the cylinder is always a good thing, right?

 

[The Dude]

I think I push my rig pretty hard and I have never found the need for "more power" when actually offroading. IMO that should be taken care of with proper gearing.

But there are lots of times that I have the turbo spooled up, but I wouldn't say that I have ever seen the EGTs in trouble while on the trail.... Well maybe on some of those really long hill climbs in Alaska.

If wayne would jump on the SOA bandwagon and get some big tires on his rigs, he would see his turbo spooling

 

[crushers]

Dude,
I have no need for larger than 36s and i like stability. anyway, it is fun being the little guy pulling out the bigger boys.

what is that saying?
"why run when you can crawl"

 

[jb BJ73]

Yes, it......well....compensates. What the specs or stats are is beyond my knowledge, as is where the max out point would be. I did not agree with the generalized statement "that increasing the boost without modifying the fuel would only give limited results". I agree that increasing the fuel setting above stock settings will give more results when you have looked after the air and flow side of things. And if you are aware of potential impacts and power is what your after then go for it.

Either buy or download the FSM for the 12HT. A search here will lead you to the download sites.

gb

i've got the 12ht manual already. just had a quick look through it and found the full load stopper screw on page FU-96. i assume this is what you guys are adjusting when you turn up the fuel. theres also an adjustment for the boost compensator a couple of pages up, althought that would be alot more difficult to adjust when the pump is in the vehicle.
i've got a 12ht sitting in the shed that i'm going to put in my bj73 when i get around to rebuilding it, so i'm also interested to know how to get more power out of these motors. i'm an apprentice for an isuzu dealership so i know a bit about deisels. but we never play around with fuel settings so i'm still learning about that sort of thing.

 

[Tapage]

It depends .. here in Panamá in our kind of off road .. muddy hillclibs sure your are boostng and many times do it pretty hard .. at least me ..

I'm just more prone to the electric fan idea on the intercooler than water injection .. just I'm little scary adding water on to my engine ..

 

[rideglobally]

i am a cheerleader for the water/meth injection.

whereas rolling down the road or highway a traditional air/air intercooler works great at dropping charge temps, when you are crawling through a jungle trail you don't get much air forced thru the fins of the intercooler...pretty much negating the advantage when you need it.

the water/meth injection setup works when you need it to work...and you can usually customize when the thing comes on depending on boost or egt levels.

i learned about this stuff from the old turbo Buick Regal and Grand National crowd.

here are two sites:

Snow Performance: Stage 1 Diesel Boost Cooler?

Water Injection, Methanol Injection, Alcohol Injection Systems | Coolingmist

i checked out the sites, very interesting stuff. which of the product would you recommend? i am thinking of inter cooling my 12 ht sometime in the future. what do you think about running both systems, intercooler and water methanol system?....

 

[arnott1t]

water meth

I did some tests using water methanol injection for intercooling on a 3b turbo. To be very honest I got little to no results from it. We used a shurflow pump...same as the other guys, and bought the same nozzles that they use. We also tried a broad range of flow rates from a little to alot. We saw no appreciable gains. The water was injected post turbo as we were recommended. It triggered on at about 8psi boost. The pump we used was a 24v unit. I still have most of the stuff is someone else is interested in using it. To bad it didnt work it sounded very promising.

 

[Tapage]

I did some tests using water methanol injection for intercooling on a 3b turbo. To be very honest I got little to no results from it. We used a shurflow pump...same as the other guys, and bought the same nozzles that they use. We also tried a broad range of flow rates from a little to alot. We saw no appreciable gains. The water was injected post turbo as we were recommended. It triggered on at about 8psi boost. The pump we used was a 24v unit. I still have most of the stuff is someone else is interested in using it. To bad it didnt work it sounded very promising.

and you nclude proper amount of fuel .. how about your EGT numbers to share with us .. ?

 

[arnott1t]

We ran a 3B turbo with about 12psi max boost. We then tuned teh EGT's to hit about 1000f post turbo when running it as hard as we could. Then we recorded our temps with the water injection on the same hard runs as well as cruising at 110km/hr. We saw no gains from the water methanol injection....not sure why it just didn't work. My best guess is that we weren't getting good atomization of the water. We tried the nozzles a bunch though and they sprayed real good.

 

[zander]

I am confused about how to increase boost in my stock 12H-t. From what I can see I need to add a little valve that I assume restricts vaccuum to the turbo wastegate and this increases boost?

I am at hi altitude (6000 ft and above) and getting high EGTs that I want to decrease. It sounds like I can decrease EGTs by increasing boost to get some more oxygen into the burn as long as I leave the fuel alone.

(BTW I do have a 3" exhaust already)

 

[Tapage]

I am confused about how to increase boost in my stock 12H-t. From what I can see I need to add a little valve that I assume restricts vaccuum to the turbo wastegate and this increases boost?

more less the idea .. what is about to block the real boost to thewastegate via boost controller until it reach your desired boost ...

I am at hi altitude (6000 ft and above) and getting high EGTs that I want to decrease. It sounds like I can decrease EGTs by increasing boost to get some more oxygen into the burn as long as I leave the fuel alone.

I will start reducing the amount of diesel at the IP .. ( been injected ) and then increasing the boost a bit ..

 

[Stone]

I am confused about how to increase boost in my stock 12H-t. From what I can see I need to add a little valve that I assume restricts vaccuum to the turbo wastegate and this increases boost?

I am at hi altitude (6000 ft and above) and getting high EGTs that I want to decrease. It sounds like I can decrease EGTs by increasing boost to get some more oxygen into the burn as long as I leave the fuel alone.

(BTW I do have a 3" exhaust already)

The manual boost controller (Grainger valve) basically isolates the wastegate from the boost being created until it hits the pressure that you set it on. The stock wastegate will remain good for the original factory setting, but it doesn't feel any boost until the valve opens up at the higher set pressure and causes the wastegate to dump.

I bought a cheapie Ebay boost controller and installed it into my 12H-T in my FJ80...and the thing works awesome. Currently running in the neighbourhood of 15 psi max and it can still leave a grin on my face as I step on the throttle. Fuel is factory setting, the extra power coming from the boost compensator.

 

[Tim-HJ61]

You will find my website covers off most of what you are asking about:
Increasing power output of a 12H-T

Whilst I increased the boost first to 12psi and that made a difference, installing a 3" exhaust really added a heap of torque and capacity to pull up long hills without increasing my EGT.

Once breathing was sorted, I added more boost. Then I added more fuel - three turns in all at the end. The website has pictures of where to do this. You'll also see the links to the fat exhaust instal. No black smoke, so maybe an extra half turn is on the cards, but EGT's will be more of a problem. Turbo now 'just' lights up the overboost light at 15psi.

All in all I now have a FAR different machine that will hold speed up most of the longest hills in my area, only needing to back off when the EGT hits 650°C. Economy has not got any worse and on long runs it appears to have got better. It will spurt away at 100kmh in 5th quite happily, and I'm running slightly taller tyres than standard - 265/75 16 so with standard wheels the power will be even more noticable.

I can get the rear end to skip out on wet bitumen if I want to be a hoon - and it's burning 100% waste veggie with diesel startup/shutdown. I'm as happy as chappies.....

Tim

 

[Tim-HJ61]

I am confused about how to increase boost in my stock 12H-t. From what I can see I need to add a little valve that I assume restricts vaccuum to the turbo wastegate and this increases boost?

I am at hi altitude (6000 ft and above) and getting high EGTs that I want to decrease. It sounds like I can decrease EGTs by increasing boost to get some more oxygen into the burn as long as I leave the fuel alone.

Zander it's pressure that opens the waste gate not vacuum. But you are right, more air will decrease your EGT. there's a limit on how much air your CT26 will push through.

If you have an EGT gauge and a 25psi turbo gauge, try blocking off the pressure line to the waste gate with a bolt down the middle and a clamp around it, then drive a test run without the waste gate opening at all. You are likely to pop around 22psi with a standard CT26 and will see how all that extra air affects your EGT's.

Then you can make a decision about how courageous you are at leaving the waste gate disconnected, or whether you want to wind it back to 15psi for piece of mind. Disconnecting it for a few test runs isn't likely to break anything.

The other option is an intercooler to reduce your EGT, or water injection.

Tim

 

[zander]

Thanks to all of you for the advice. I have ordered one of these boost controllers:
EXTREME PSI : Your #1 Source for In Stock Performance Parts - Hallman PRO RX Boost Controller Kit

Mainly because it has an option of being controlled from the cab in case I do want that in the future. I like the idea of testing the system with the wastegate locked out to see what the effect will be. Thanks again.

 

[Stone]

I should probably mention that my CT26 is a fresh rebuild off of a Toyota Supra, not a stock 12H-T unit. Gbentink thinks highly of the Supra turbos with the high boost that he runs in his engines, and that gives me confidence in this unit.

 

[Dougal]

this has always puzzled me...
when you are 'crawling' through the bush you are producing no sustantial turbo boost, it is the turbo boost that creats the heat that the intercooler removes. if there is no heat then what is the need for an intercooler or water injection?
water injection is usless at crawling speeds, as is an intercooler, propane injection or even a trubo for that matter. it is when loading up that all these units come into play.
if the turbo is loading up then the speed is enough to move air over, through the intercooler.

cheers M8s

I'm agreeing with Crushers on this one.
The only situations where you use enough boost to need an intercooler offroad are deep sand and deep mud.

In which case a front mount which is having air sucked through by the engine fans would work fine.

Regarding turning up the boost without the fuel.
I've found it gives an increase in torque down low but less power up top. Reason being the improved efficiency in the mid range but at higher rpm it takes a lot more power to pump and compress that extra air. This costs power.
Your best top-end power will be the minimum boost to burn your fuel cleanly, but EGT's will be a problem. Hence sensible people trade off top end power for safe EGT levels.

 

[Tapage]

Out of my books ( that actually are only reading by me ) pushing a CT26 far up to 22 PSI wastegate disconected would be nice for a run .. but it will push much more hot air ( out if it´s surge and efficience island ) than good boost ( that means more Oxigen ) not talking about the max rpm that it's designed to run ..