Experience with PDI Intercooler and HJ61 12ht (1 Viewer)

[Griffcl84]

First off what I'm working with.
1989 HJ61
24v
12HT
A440
Stock Turbo
3" straight exhaust after the dump, the start of the performance modifications

Main querry is on PDI intercooler fit on HJ61. But here is what I did with my diesel this past weekend.

I finally got around to installing a pyrometer (pre-turbo) and AEM boost controller this past weekend. Without messing with the boost, ie leaving stock, I decided to take her for a spin and see what my EGTs were reading. Well on a short little climb up a hill hit ~3000 rpms the EGTs popped up to 1300. I immediately let off and let it cool back down. Makes me concerned about how Ive been driving the beast. Frequently climb two decent hills, RPMs only ever spike for a few seconds. Still, leaves me a little wary of what those temps have been.

Pulled up to the house and smelled burning and let out a stream of expletive's at myself. Popped the hood and the fan belt is is broke in half and hanging down. Not the end of the world, but could have been very bad. I have one due in tomorrow to replace. Note, engine temps stayed average, just above the 1/4 mark. Total trip was 10 minutes. However the EGTs have me wanting to fast track an intercooler and might just throw in a new turbo in while I'm at it.

So a few questions for you 12HT cruisers.

1. EGTs. Crazy high for the RPMs? Fan/Condenser/Pump shouldn't affect this on such a short drive right? Just curious.

2. PDI mentions recesses in their 12HT intercooler to accommodate condenser lines. Any experience? Ive seen a few threads with mention of still needing to do some decent chop jobs on the front grill. Would like to keep the aesthetic of the grill. Chopping behind the scenes is perfectly fine.

3. Thinking about the GTurbo Grunter, worth the upgrade with stock fuel pump? Not wanting to mess with pump and injector upgrades right now.

3. WA intercoolers. Worth the trouble. Seems like one more thing to have to potentially have problems with.

Any and all thoughts are appreciated

 

[AussieHJCruza]

Getting an EGT gauge is a surefire way to dampen your driving enthusiasm!

1) yes they're high, although you won't hurt the 12HT at 1300f. Fan/Condenser etc. Will have no influence on EGTs. Fuel/Boost and your right foot control this. The challenge with an auto is that what you need to do to keep it cool (run with the converter locked as much as possible) is usually about the opposite of what you want to do to keep EGT under control ( let the engine get up in the RPM)

2) I've never fitted a PDI cooler to a 60 but I'd say that from looking at them you'd need to do a good old chop job on the grille.

3) I wouldn't bother with the grunter, run a healthy stock turbo at 15psi or go to grunter extreme or bad boy, or something in the size of a TD05H-16G. If your stock turbo needs work, then it's probably a good time to upgrade. There's fuel in your stock pump to about 18psi with a Grunter Extreme.

4) some like W2A and might have more insight. I wouldn't bother, a good A2A is much simpler and arguably more efficient.

5) if you're going to fit a front mount cooler, make sure your cooling system is good beforehand, specifically well functioning fan clutch, condenser-radiator-shroud well sealed etc. There's no downside to cooler intake air however if you're only just keeping her cool now, it's not going to help.

 

[ATL Cruiser]

I installed a front mount PDI in my 77. It went fantastic, and the company was great to work with.

The grill did require significant trimming on the backside. There is almost a full inch to spare there, so PDI uses that space for more intercooler depth.

The grill trimming is really easy. The hard part is making it look good. I used a small Dremel to do it. But if I were to do it again, I would use a cut off wheel with the biggest 4-6" disc I could find. Much easier to make long straight cuts.

 

[mudgudgeon]

@AussieHJCruza hit most points.

You didn't mention what psi boost you have?

More boost can = more air, and lower EGTs (depending on your current boost, turbo etc)

1300⁰f for EGTs is getting up there, but not something to panic about yet.
If it's a peak that you see for a few seconds on a steep hill climb, I wouldn't worry.
If you're seeing it for minutes at a time on the highway it's more critical. Or if you were seeing it constantly while towing a boat etc

Personally, I think water to air intercooler l is unnecessarily complicated, and for the most part air to air is better suited to a diesel

 

[Griffcl84]

Getting an EGT gauge is a surefire way to dampen your driving enthusiasm!

1) yes they're high, although you won't hurt the 12HT at 1300f. Fan/Condenser etc. Will have no influence on EGTs. Fuel/Boost and your right foot control this. The challenge with an auto is that what you need to do to keep it cool (run with the converter locked as much as possible) is usually about the opposite of what you want to do to keep EGT under control ( let the engine get up in the RPM)

2) I've never fitted a PDI cooler to a 60 but I'd say that from looking at them you'd need to do a good old chop job on the grille.

3) I wouldn't bother with the grunter, run a healthy stock turbo at 15psi or go to grunter extreme or bad boy, or something in the size of a TD05H-16G. If your stock turbo needs work, then it's probably a good time to upgrade. There's fuel in your stock pump to about 18psi with a Grunter Extreme.

4) some like W2A and might have more insight. I wouldn't bother, a good A2A is much simpler and arguably more efficient.

5) if you're going to fit a front mount cooler, make sure your cooling system is good beforehand, specifically well functioning fan clutch, condenser-radiator-shroud well sealed etc. There's no downside to cooler intake air however if you're only just keeping her cool now, it's not going to help.

Solid feeedback. Yeah I think I'll hold off on the turbo. Nothing wrong with the stock, no need in dumping out another 2.5k for something that isnt needed. I think I'm going to go with the PDI, probably in a couple months. Good call on double cheking all of the AC components. Mounting the bumper with winch installed was a PIA by myself, would prefer to minimize how often that has to happen.

 

[Griffcl84]

I installed a front mount PDI in my 77. It went fantastic, and the company was great to work with.

The grill did require significant trimming on the backside. There is almost a full inch to spare there, so PDI uses that space for more intercooler depth.

The grill trimming is really easy. The hard part is making it look good. I used a small Dremel to do it. But if I were to do it again, I would use a cut off wheel with the biggest 4-6" disc I could find. Much easier to make long straight cuts.

Right on. I figure if its just standoffs and such on the back side I can live with it. I figured I would mark and go with the angle grinder and finess with the dremel. Dremels are handy, but they are slow AF!

 

[Griffcl84]

@AussieHJCruza hit most points.

You didn't mention what psi boost you have?

More boost can = more air, and lower EGTs (depending on your current boost, turbo etc)

1300⁰f for EGTs is getting up there, but not something to panic about yet.
If it's a peak that you see for a few seconds on a steep hill climb, I wouldn't worry.
If you're seeing it for minutes at a time on the highway it's more critical. Or if you were seeing it constantly while towing a boat etc

Personally, I think water to air intercooler l is unnecessarily complicated, and for the most part air to air is better suited to a diesel

Boost was ~6.8

I was hoping the added boost would do what is does and cool EGTs a bit

Thanks for at least making me feel better about the temps I have been likely pushing. The hills around here can be steep, but nothing long and sustained.

My thoughts exactly on the WA intercoolers. Plus with it being a 24v system it would be one more thing to wire into my 12v aux battery

 

[bj70bc]

in my experience with a bit more boost (and bit less fuel) you'll see that egt temp come down.
intercooler will be icing on the cake and give you that safety factor for hot days/long runs etc.
air to air is arguably 'better' and definitely more bullet proof, however i put an a/w in, and in my driving situation (4x4 slower harder pulls more frequently) it works well and only ever gets warm after a whole day hitiin the trail hard.
my a/w pump is running off the 24-12 converter

i have mine tuned so i have to push it hard to get to 1250... but it still can get there, my egt gauge has a red light that comes on at 1150 so it gives you fair warning

 

[mudgudgeon]

Boost was ~6.8

I'd guess more boost will be your friend.

The GTurbo efficiency range will give you way more boost than that without super heating the intake air charge.

More boost without touching fuel will lower EGTs right across the range. With a leaner air fuel ratio, combustion temp will be lower. I'd suggest boost in the 12-15psi range.
You may also get a bit more power out of it if the fuel settings are currently a bit rich.

I'm not super familiar with the 12ht, but I know GTurbo will be very familiar with them.

Maybe give GTurbo a shout out for a recommendation and a sanity check on boost level.

 

[ATL Cruiser]

I'd guess more boost will be your friend.

I'd suggest boost in the 12-15psi range.

Agreed. 7psi is really low.

Boost doesn't kill diesels. EGT (from too much fuel, too low AFR) kills diesels. You could boost to 40psi, and if you don't touch the fuel screw, it's a non-issue (apart from the turbo exploding).

I'm around exactly that. 12-15psi with fuel adjusted to match. EGTs are happy.

 

[cruiserpilot]

You’re asking all the right questions.
I run a home made FMIC - I passed an aspect of mine to PDI at the time he was having issues getting
it to fit with the square headlights. PDI quality is second to none. Just have to remember it’s not much
good at slower speeds as reduced airflow.
I have a GTurbo running controlled boost @ 20 PSI. My 12HT has almost 400K on it.
I‘m careful about EGTs, to me 1300 F is my nervous high. Note: if your EGT is active and you are
climbing and accelerating and EGT climbs to max on a hill so long as it reacts to cool down with
gear shift or power reduction or load reduction then don’t panic about it. It’s supposed to move
around and it will get hot under load. If EGT stalls at high temps, and you’ve reduced load etc, then
I’d look for reason.
Grill clearance for intercooler. I used a 3”x12x24, it’s huge. I used 2 1/2” piping. In the bottom corners
of your grill is where you will maximize the thinning if your grill. I used a 4 1/2” 80 grit flapper wheel.
Basically it sands with heat and melts the plastic evenly and consistently. It will harden where it
rolls over and you just scrape it off with a knife/scraper.
Overall, a front intercooler and more boost is great enhancement for a 12HT. Get advice on fuel management
and acceleration adjustments on the fuel pump.

 

[cruiserpilot]

I knew it would come to me in my sleep. I know of several guys who upgraded to
WINK turbos. Original housing but inner workings modernized with technical
upgrades. Really worth a look.

Wink 4x4 - Turbochargers

www.wink4x4.com