bcsteel
SILVER Star
When I pickup the 61 I’ll let you know about the exhaust dump for sure
12HT Intercooler & GTurbo upgrade LHD 60 (1 Viewer)
- Thread starter cruiserpilot
- Start date
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Thank you for this write up. I really enjoyed the pictures and your logic when working on this stuff reminds me of myself. Stubborn to do something a certain way even if it's twice the work 
I'm thinking about a Gturbo for my latest 12ht I'm putting together. It's still on the stand so I have time to decide and not really even sure what rig it's going to end up in. I used that same 3'' dump on my other 12ht and was just about to order another for this latest build. Let me know if you want to ship it to the states although I don't know that it would be much different then me ordering from AU since it has to go through customs either way. Anything done to the internals on your 12ht like upgraded pistons, headgasket, or studs? How many km's? How much boost do you plan on running?
I'm thinking about a Gturbo for my latest 12ht I'm putting together. It's still on the stand so I have time to decide and not really even sure what rig it's going to end up in. I used that same 3'' dump on my other 12ht and was just about to order another for this latest build. Let me know if you want to ship it to the states although I don't know that it would be much different then me ordering from AU since it has to go through customs either way. Anything done to the internals on your 12ht like upgraded pistons, headgasket, or studs? How many km's? How much boost do you plan on running?
Great Tech here
- Thread starter
- #44
So I’ve officially stopped grinning every time I drive it. 
No, I’m lying.
Took a bit to get the pressure lines sorted out. My information was to maximize
the performance of the GTURBO to 20 psi. I initially ran the line from the turbo
to the aneroid at the rear of the injection pump where the low throttle fuel adjustments
are made. This is so as soon as the turbo spools up, the injection pump increases the
fuel as required.
If you noticed I installed two boost fittings right at the throttle inlet adapter. One goes
directly to the wastegate, so the wastegate will adapt to the actual boost right at
the engine inlet.
The other inlet fitting goes to the boost gauge.
This resulted in me getting only 16 PSI, no matter what I did.
And I did a couple of dozen runs adjusting fuel, re-running pressure lines.
No, I’m lying. Took a bit to get the pressure lines sorted out. My information was to maximize
the performance of the GTURBO to 20 psi. I initially ran the line from the turbo
to the aneroid at the rear of the injection pump where the low throttle fuel adjustments
are made. This is so as soon as the turbo spools up, the injection pump increases the
fuel as required.
If you noticed I installed two boost fittings right at the throttle inlet adapter. One goes
directly to the wastegate, so the wastegate will adapt to the actual boost right at
the engine inlet.
The other inlet fitting goes to the boost gauge.
This resulted in me getting only 16 PSI, no matter what I did.
And I did a couple of dozen runs adjusting fuel, re-running pressure lines.
- Thread starter
- #45
In my opening post my inside help was a fellow in Perth. He did a blog and it is
very detailed as to how the final setup should be. I did install a boost controller
originally, but during my redneck test flights of trying to get more than 16 psi
I turned the screw too far out, and it came apart in my hands. So bugger that!
i ended up phoning Rhys @ GTurbo on SKYPE, it’s less than .03 cents/ min.
There is a small T-Fitting which came with the boost controller. This I had not
installed as I didn’t know what it’s purpose was. Turns out, it is on the line from
throttle inlet to wastegate inline, supposedly just after the boost controller.
Now for some reason this pressure line needs to be open to ambient air in order
to correctly ‘signal’ the wastegate to fully open.
OMG! Seriously, INSTANT full boost if not careful!
Next run, the boost came up so fast through 15 psi that by the time I’d reacted
and come off the throttle it was through 20 psi and climbing.
very detailed as to how the final setup should be. I did install a boost controller
originally, but during my redneck test flights of trying to get more than 16 psi
I turned the screw too far out, and it came apart in my hands. So bugger that!
i ended up phoning Rhys @ GTurbo on SKYPE, it’s less than .03 cents/ min.
There is a small T-Fitting which came with the boost controller. This I had not
installed as I didn’t know what it’s purpose was. Turns out, it is on the line from
throttle inlet to wastegate inline, supposedly just after the boost controller.
Now for some reason this pressure line needs to be open to ambient air in order
to correctly ‘signal’ the wastegate to fully open.
OMG! Seriously, INSTANT full boost if not careful!
Next run, the boost came up so fast through 15 psi that by the time I’d reacted
and come off the throttle it was through 20 psi and climbing.
- Thread starter
- #46
So I’ve got to get the boost controller installed. I’ve turned the fuel screw on the
front of the injection pump out almost fully. The fuel screw on the rear of the injection
pump needs a bit more finesse. The fuel screw on the rear of the pump adjusts low end throttle
fuel increases. So I’ve slowly been turning the screws at 1/4 turn increments. Too much - and
black smoke and unhappy following neighbours. I’ve got it so the acceleration is as
perky as an empty 13BT in my BJ74!
This is a different truck now. I can run from 80-110 kph in 5th up 6-8% grades easily.
Let me be clear about one thing as well - NO turbo lag, none, zero. I can be travelling
at 100 kph, holding 15 psi up a grade and as soon as I make a throttle adjustment I get
an instant reading on the boost gauge. Throttle down - boost up, throttle off - boost down.
i had in the back of my mind worried a bit about the inlet tubes on the intercooler being
3” and 5” long, thinking that the airflow might stall there. Resulting in turbo lag and high EGTs
but this just isn’t happening.
This turbo puts out more than enough through the intercooler system. Also I did a full leak check
and all the fittings are solid. Used glass cleaner in a spray.
front of the injection pump out almost fully. The fuel screw on the rear of the injection
pump needs a bit more finesse. The fuel screw on the rear of the pump adjusts low end throttle
fuel increases. So I’ve slowly been turning the screws at 1/4 turn increments. Too much - and
black smoke and unhappy following neighbours. I’ve got it so the acceleration is as
perky as an empty 13BT in my BJ74!
This is a different truck now. I can run from 80-110 kph in 5th up 6-8% grades easily.
Let me be clear about one thing as well - NO turbo lag, none, zero. I can be travelling
at 100 kph, holding 15 psi up a grade and as soon as I make a throttle adjustment I get
an instant reading on the boost gauge. Throttle down - boost up, throttle off - boost down.
i had in the back of my mind worried a bit about the inlet tubes on the intercooler being
3” and 5” long, thinking that the airflow might stall there. Resulting in turbo lag and high EGTs
but this just isn’t happening.
This turbo puts out more than enough through the intercooler system. Also I did a full leak check
and all the fittings are solid. Used glass cleaner in a spray.
Go to the first post of this thread and you'll find it
Go to the first post of this thread and you'll find it
Doh - Headslap! I've read Tim's articles a number of times - really appreciate the info on what you've discovered here, thank you! I'm putting a 12h-t + gturbo grunter in my LHD 60 so this is very germane.
@cruiserpilot If @bcsteel doesn't want it, I'd like to buy that dump pipe / adapter from you. I'll be needing it as soon as next week.
Last edited:
- Thread starter
- #51
You'd do better to order directly from them. It takes 4 days from order to delivery. Your dollar isI'd like to buy that dump pipe / adapter from you. I'll be needing it as soon as next week.
better, cheaper for you to buy direct. I'd bet shipping from here to there is more or less the same.
Sounds good. Cheers!
Ended up ordering the whole stainless 12h-t exhaust system including down pipe and muffler. Glen was both a character and great to work with. With the exchange rate and the shipping, it was a good price - $770 including shipping to the west coast.
- Thread starter
- #54
Very good!
- Thread starter
- #55
Here is pulling up a 6% grade and the second is just cruising, both 5th gear. After 1200 kms of hot rodding, pulling my trailer with ATV and other cargo back and forth over the Malahat, averaging 10-15 kph faster than I normally would have driven, still getting same average fuel economy. Can’t wait to run a nice long road trip without 150 stops and starts.
- Thread starter
- #57
Nope. LOL!
Haven‘t had time to tear back into the dash. Got a problem with the temp sender.
I think there is a plug on the side of the oil cooler, and I pulled it from previous gauge
but the thread is really coarse, and I haven’t had a chance to just attach a lead
and see if I can get a signal to a new gauge. If it works, then I’ll get temps. In reality,
it’s a 12HT and it’s winter So not an issue. My factory gauge works fine and it’s
not changed it’s indication at all, so I’m not that worried.
Haven‘t had time to tear back into the dash. Got a problem with the temp sender.
I think there is a plug on the side of the oil cooler, and I pulled it from previous gauge
but the thread is really coarse, and I haven’t had a chance to just attach a lead
and see if I can get a signal to a new gauge. If it works, then I’ll get temps. In reality,
it’s a 12HT and it’s winter So not an issue. My factory gauge works fine and it’s
not changed it’s indication at all, so I’m not that worried.
Ummm, what side of the road are you driving on Cruiserpilot, I thunked you were South African boy.
- Thread starter
- #59
West Coast of Canada. Lived in Malawi when I was teenager. I am a member of Community
Forum in SA. My avatar pic I switched Tim, should he RIP since his passing last month. The big
tuskers have always fascinated me, to see them in the wild is amazing. Not to mention, they
represent pretty fine beer as well!
Yip, the avatar and "Ladysmith" got me. We have a Ladysmith here in South Africa as well. And , sorry to say, we brew much better beer in SA .
Still enjoying rebuilding my 12HT, and still don't have a clue what I am going to do with it.
G
Still enjoying rebuilding my 12HT, and still don't have a clue what I am going to do with it.
G
