12HT Intercooler & GTurbo upgrade LHD 60

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So I searched pretty thoroughly for ideas and previous builds.
There was one blog from W Australia that really stuck with me. A long term build with very complete ideas and not without it's own
issues. www.peoplehelp.com.au/landcruiser/power-upgrades/12h-t_power_boost.html
So before I go any further special thanks to Tim for his countless emails and long phone call over Christmas to help iron out the details.
I decided on as big an intercooler as I could fit, or not. I also decided to get an upgraded turbo so I can pull my utility trailer with ATV
more comfortably on long trips up north. Some of the grades are 13% up north and they are long, several kilometers. Vancouver Island
has one grade at 18% over 5 kms long. It kills.
Anyhow, here is the exciting stuff. Impossible to believe so I attach the invoice for fun. June 21 from Perth Aus, to Ladysmith Canada
by June 25th. 4 DAYS!! DHL rules.

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Intercooler - here's where the work happens.

I used the 24x12x3" intercooler. It's kinda huge. I bought the smaller one first on advice from a couple of people
who used the HP rating to indicate the size required. 60060 18x9.5x2.5" rated for 400 hp. You'd think that was
plenty but I've got different views and it's not enough.
The 60001 24x12x3 that I went with is rated for 700 hp. This is the size that ultimately was used in the blog above.
So I did some math. The smaller intercooler has 427 cu inches of cooling area. The 60001 has 864 cu inches of
cooling area. Twice the cooling area. To me that was significant.
Another source that I really respect, and did get some responses from was PDI. His 80 series intercoolers are
very popular and I've seen a few on this side of the ocean.
I posted this because the 1HDT intercooler he supplies is just slightly smaller than I am using but his is a custom
fit and it works with the 80 series perfectly. But I think right around 800 cubic inches of cooling area.
The owner and I talked about tubing size as well, BTW SKYPE makes for cheap trans oceanic phone calls.
I'd been looking at just using 2" diameter piping, but felt more flow would be better. I felt 3" piping would
be excessive. So 2 1/2" is what I went with. According to information from PDI, the torque curve for the
12HT comes on a bit quicker and lasts longer through the power curve according to dyno tests done down under.
But damn, it's huge up there.

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Also, since I'm in there. Needed new silicone connection intake boot for the larger diameter inlet on the
GTurbo. I also ordered a manual boost controller from PDI as well.
Then I got on to Megazip.net and ordered a box of odds and ends. New upper and lower rad hoses, thermostat
and gasket. Also new rubber liner for inside of air cleaner so the filter seals as best as possible. And a new inlet boot for
fresh air inlet as mine was old and cracked. From Europe new injector nozzles for the injectors, and hopes to get
them away for servicing as soon as I can.

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Anything is possible if you are a little creative. I did the exact same with my 81, ordered Gturbo and 24x12x3 intercooler with 2.5” tubes and made it fit.
Good luck on your project.
 
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This intercooler has 3" inlets on it. I decided early on that it was going to have to be modified. The original intercooler
I bought had inlets not at the bottom. This design works way better with 60, but the intercooler itself was too small.
The company that I really liked for quality is Vibrant Performance. But they recently discontinued their intercooler line
to just 3 basic sizes. Really disappointing since the 12x24x3.5" intercooler they make is perfect for inlet positioning
but there was no way to make the 3.5" thick intercooler work without major radiator support structural changes.
I've got dual 31 series batteries so making sure the piping fit underneath without interference was important.
 
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This intercooler has 3" inlets on it. I decided early on that it was going to have to be modified. The original intercooler
I bought had inlets not at the bottom. This design works way better with 60, but the intercooler itself was too small.
The company that I really liked for quality is Vibrant Performance. But they recently discontinued their intercooler line
to just 3 basic sizes. Really disappointing since the 12x24x3.5" intercooler they make is perfect for inlet positioning
but there was no way to make the 3.5" thick intercooler work without major radiator support structural changes.
I've got dual 31 series batteries so making sure the piping fit underneath without interference was important.
If you want top in and out why not flip your intercooler upside down? There are mounts on top and bottom for mounting.
 
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Couple of things to work out in the beginning. The FMIC is inert, no moving parts and I also wanted to build it
so I didn't have to remove it to service anything, whether it be alternator or priming the injection pump if I run
out of diesel. Also, I cut it really tight and I didn't want to not be able to remove the radiator easily as well.
I ended up building the angle bracket on top using a piece of 2 1/2" square tube all cut up. I wanted steel
so I could weld supports for the hood latch and I wanted it to be really overbuilt to stand up to years of
hood slamming.

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I'm writing this all out long hand so it explains how and why I do it this way. So the intercooler has been centered and the
bottom of the hood latch is about 1/4" from the top of the mounted intercooler. I welded a couple of stout 1/4" thick stubs
to the top of the bracket. Then I threaded holes into them each. It is that bolt head you see just left of the hood latch. With
that bolt in there and that stub goes right to the bottom of the rad support cross member it's completely firm. NO hood bounce
and solid release. I used factory threaded bolt holes on each end.
Another thing is the upper radiator release mounting bolts that are rubber isolated. They normally bolt through from the front
with captured nut on the radiator side. So you can see I reversed the nut and bolt and then used JB Weld to weld the hat nut
to the inside of the rad support so I can easily remove the radiator with the 4 bolts are required, but all from behind the support
now. The lower brackets for the IC are just 2 1/2" pieces welded in place.
I used thick rubber toilet bowl washers for isolator washers as they are virtually indistructable and quite thick too. Factory
SS bolts I found are the bolts I used to mount the IC.
 
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I had cut the duct holes earlier for the smaller intercooler with the upper outlets, but then had to break out the plasma
cutter to make them lower and out more. This is the final position for the intercooler. By design no matter what servicing
this truck needs, aside from an accident, I won't have to move or remove or work around this ever.
 
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From the beginning I had decided to not just work around silicone boots. I wanted solid tight radius bend inlets.
So I vent to Vibrant and got these two cast elbows. I have every intention of cutting the inlets off the IC, just
measuring up to see what I was dealing with. In the end, I went with a closer radius elbow, still made by
Vibrant but thinner polished version.

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Always mark stuff, - L - R - front - rear
That intercooler was off and on many times, the position of the brackets and holes were to individual
locations and this way it always goes back together the same way.
I'm mentioning this for the DIY guys who are just looking for tips.
I also made sure later on to lay a piece of angle on the round tubing and draw SHARPIE lines on all quadrants
so the angles are consistent and I don't lose my place or position.

I nearly messed up one of the elbows trying to get the angle right, ended up, as you can see measuring the initial
perpendicular line, then trying to measure the angled offset. Saw it was wrong, and then promptly went even further
wrong!! Then I got it right, so measure twice, three times or even four! Before you cut. These things are $40 ea, don't
want to mess them up

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This is the initial angle finding. I used a lot of yellow painters tape. That stuff is amazing. But now the idea
has shape. These are 3" elbows with 5" legs. I discussed with a couple of guys in Australia about cutting
these shorter and the possibility of turbo lag. The result is the turbo produces air fast enough that for
my purposes it would be fine. Good flow, no restrictions planned.
In the top photo you can just make out the shiny tip of the vacuum connection off the alternator. I'm trying to bring the
angle just straight back and up to clear the inner fender bump. What can't be seen is the third bolt from the radiator
mounting bracket inside the support. More on that next.
The RH side I decided to be more aggressive with bringing the angle inside of 90 degrees and up so I planned a straight
pipe to below the inlet adapter. I also needed the RH side to be well clear of injection pumps, webasto fuel pump,
PS lines and the obvious air cleaner and cross tube. The bottom pic shows how much angle I was aiming for.

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In this pic you can see the inner radiator support bracket. The third bolt is plasma'd off. I ground it down and
hit it with a weld. I figured it was something I would only ever removed in the event of an accident, and quite
frankly if I'm looking at that, chances are it will just be one piece of many I'll be replacing. The lower radiator
mounting bolt has to be accessible and radiator removal without any interference from the IC piping is paramount.
Just not accepting having to remove IC piping for any maintenance. I split my fan shroud. I'll post some pics of that
here now. At the top of the pic is the reversed bolt from the upper radiator mount. So remove the upper bolt, the
lower bolt, the two bolts from the split fan shroud, hoses and its done. Last test removal for radiator from start to
finish - 3 1/2 minutes after draining. Very cool!
Edit: Lower pic is the 3rd rad support bolt removed and cleaned out then just welded it. Easy to reverse.

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Very nice work!!
 

Ophir

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Also, since I'm in there. Needed new silicone connection intake boot for the larger diameter inlet on the
GTurbo. I also ordered a manual boost controller from PDI as well.
Then I got on to Megazip.net and ordered a box of odds and ends. New upper and lower rad hoses, thermostat
and gasket. Also new rubber liner for inside of air cleaner so the filter seals as best as possible. And a new inlet boot for
fresh air inlet as mine was old and cracked. From Europe new injector nozzles for the injectors, and hopes to get
them away for servicing as soon as I can.

View attachment 2189602View attachment 2189603View attachment 2189604

Who was your vendor for the nozzles? Thanks for posting - watching closely. :)
 
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Who was your vendor for the nozzles? Thanks for posting - watching closely. :)

Here you go. Looks still in business. I don't usually shop eBay but this guy rates over 99%
So I took a chance. I've been burned a few times on eBay/

 
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There are no adapters out there for the 12HT intake. So I had to make one. I went back and forth between
aluminum and SS for the piping. In the end I found a welder willing to do the TIG for it all and he
recommended aluminum for a couple of reasons. First, cools fast and doesn't retain heat as much.
Something to do with misting inside the piping when you TIG SS it creates a residue that needs to be
flushed or something. Has to be cleared with gas. I wanted lighter, less heat so I was sold on Aluminum.
I have to say something here about Vibrant Performance, they came through with such exceptional
customer service out of Toronto.
Here are the close radius elbows I used. I ended up using in 2 1/2" - 3 elbows, 2 18" straight pipes.
The IC elbows were 3" elbows.
 
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I draw everything out before I do anything. Houses, shops, decks, engine inlets. I had to make three inlet adapters
before I got it right. First one was 1/4" aluminum then the second and third 1/2". The inlet measures 2 1/8".
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Inside of the piping being 2 1/2" OD is 2 5/16" ID. So 3/16" difference. Hard to center that hole by hand using a gasket
cut out template but that's what I did.

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Then I drilled some holes and centered it up. I used a holes saw from the bottom, and a larger from the top then
die grinder fine bit to run the slope. Bit of massaging and its so tight a fingernail won't catch on the edge.

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