12HT rebuild parts

[Rookie12ht]

Hey guys,
12ht rebuild time...looking for contacts for quality rebuild kits etc.

Im in Aus, looking for overseas supliers, to expensive for cheap parts over here.

Any help appreciated.

Cheers.

 

[watrob]

There are more 12ht parts here in Aus than overseas. The kits here are shipped all over the world. And if you are buying a rebuild kit get a good quality one. I just rebuilt a 12ht.

 

[Crick60]

Nice rebuild watrob!!!!

Plenty of good places here in aus but be ready for a premium price compared to the 2h and other similar motors. For a shop to rebuild you're looking around the $4k-$6k mark.

 

[Rookie12ht]

Is there such a thing as a quality rebuild kit in Aus for a 12ht...

Unless your buying genuine, there is diesel power and maybe a couple others.

Im not looking for just a standard rebuild kit.

Im looking for more along the lines of custom parts.

Im currently running a GTurbo at 20psi but at 659,000klms its due for a bottom end rebuild
(head done 50,000klm ago)

Will be regrinding cam and porting head this time around, plus modding fuel pump as its maxed out with current setup.

 

[watrob]

I know, but these motors are nearly 30 years old and just about everything in them has to be rebuilt if you want to get another 20years out of it. Turbo also, and the last thing you want is to pull it down again because missed something.

If I can get another 30 years out this engine I will be happy? $6k over 30 years is pretty cheap.

 

[Christian]

I live in Denmark, and plan on getting a rebuild kit from AUS, that's about half way around the world, but the cheapest...

 

[watrob]

Is there such a thing as a quality rebuild kit in Aus for a 12ht...

Unless your buying genuine, there is diesel power and maybe a couple others.

Im not looking for just a standard rebuild kit.

Im looking for more along the lines of custom parts.

Im currently running a GTurbo at 20psi but at 659,000klms its due for a bottom end rebuild
(head done 50,000klm ago)

Will be regrinding cam and porting head this time around, plus modding fuel pump as its maxed out with current setup.

If you are going to do that I would pick another engine, one with a rotor IP, the parts are more readily available & cheaper?

 

[Crick60]

Hmmm at 20 pound you really are in the "performance" section of the 12ht so you're right custom parts are going to be the right path.

Just as a minor deviation 20psi is pretty high for the 12ht, I'm not sure that you won't be chasing the rebuild ghost for many future years running that kind of boost. For my money I'd have done a 1HDT conversion or something like that if you're looking for power.

As for parts you are better off with a custom turbo shop come manufacturer, turboglide in Russellvale NSW would be where I'd place my first call.
DO NOT GO TO WEST END.

 

[watrob]

Don't get me wrong, the 12ht is a great engine, but I thing a later model Toyota diesel would better with what your going to do. If it were me I would do the bottom end up in the 12ht, drop the boost back to 12lbs and sell the engine, you would get a good price.

 

[Spudman]

Firstly Watrob that engine is smicky smoo,

I am currently getting 15 psi boost and that's more than enough, I've got nearly 400,000k on mine, I've also got the manual boost gauge so it's basically instant, next to nil lag.

There a few kits available on eBay if you type in hj61 you'll get a few hits, they're not that expensive either.

So Rookie where's the customary photo of your rig, or this post never happened

 

[Rookie12ht]

The old 12ht is a pretty tuff engine with the right parts.

Graeme from GTurbo was telling me about a 4.73L stroker they built with 112mm bores.
They were working on a 5L at the time i bought a turbo off him.

They had custom pistons and rods made in the states somewhere and reground cranks.
Putting out some pretty serious power.

Ive been running 20 psi without any problems so far, its probably not helping my blow-by issue.
Im just rebuilding as its using oil and has a worn cam lobe so has developed a slight miss and a little under powered,
from low compression. Still a strong engine just needs a freshen up.

Thought i might aswell toughen it up a bit while im going

 

[Rookie12ht]

lol Spudman...i would know how to put pics up on here.

Shes nothing to interesting, just a turbo and 3"

Was sprung over on 37's but not at the moment as ive been using it to tow my car trailer all over the country side.

 

[Spudman]

Hey Rookie, all HJ61's are interesting, there's a couple of ways to put up pics, the easiest being when you are replying to a post hit the attach button and simply attach a photo in a thumbnail or full picture, or there's photobucket.com

So are you getting 20 psi on a boost gauge, once I go over 15 psi the over boost light comes on so I back off.

 

[Gengis]

Anyone know which company supplies ( or produces ) these pistons for the 12HT??

Regards
G

 

[Crick60]

12HT is arguably the best motor toyota has made but by the sounds of it mate it doesn't suit your purpose.

You could either wind down the t valve to hold you around 10-15max psi and rebuild using quality off the shelf parts OR do a v8 Brunswick diesel conversion or similar.

If you embark upon the attempting to make the 12ht a performance engine path you'll spend more than the carbon tax and have more headaches than a chemist full of panadol could fix. She's a tough motor no doubt but she was designed fit for purpose with maybe +20% quality for longevity and brand preservation.

 

[Lasse]

I happely run my 12ht at 1.4bar at the moment. Plan to go higher when I get around to install my intercooler and bigger exhaust. Pretty standard expect for a disconnect Wastegate and little more diesel on the pump

 

[Hulsty]

Why all this talk of turning the boost down? Its only 20psi, not much, heaps of room to go higher with more fuel.

 

[Crick60]

Only 20psi???? Most fast 4s are limited at 18psi even the sti is hating life at 28psi.
There's nothing wrong with 20psi so long as you're willing to rebuild every 12-24 months.

Here's what I don't understand: at 8-12 psi with optimal fuel adjustment (not turning your fuel up) you get huge torque and ample power why mess with that?
If you want more power you've purchased the wrong vehicle or need to spend good dollars on a transplant.
It really gets under my skin when shops turn the fuel up on diesels, what's the point??? Sure you get more power but the efficiency decreases exponentially, just buy a V8 and be done with it.

 

[niffa]

Only 20psi???? Most fast 4s are limited at 18psi even the sti is hating life at 28psi.
There's nothing wrong with 20psi so long as you're willing to rebuild every 12-24 months.

Here's what I don't understand: at 8-12 psi with optimal fuel adjustment (not turning your fuel up) you get huge torque and ample power why mess with that?
If you want more power you've purchased the wrong vehicle or need to spend good dollars on a transplant.
It really gets under my skin when shops turn the fuel up on diesels, what's the point??? Sure you get more power but the efficiency decreases exponentially, just buy a V8 and be done with it.

Each to their own mate, each to their own

 

[Hulsty]

Sounds like your in the dark ages of diesel performance. So i have been running 24psi for a few years now, by your calcs I should have rebuilt it 3 times in that time? Plenty of diesels running 20psi+ plenty from the factory too.

To the OP, which ever kit you get make sure it has "alfin" pistons which will help with the motors longevity.