KZJ78 Prado 1KZTE DIY intercooler install revisited

[kbushnz]

Hi Yah All

Starting my next mod.
Picked up donor intercooler, 2.8 Isuzu Bighorn / Trooper / Mu. $20 off TradeMe.
Bit smaller than the Prado unit, but any intercooler is better than none.



Bighorn bonnet comming, to remove/cut the scoop from and get the rubber connection flange.

Also an electric fan to mount underneth to draw air accross when moving slow (off Roading)

Need to relocate the throttle unit and TPS.
Trim down the rocker cover or find a Intercooled version from a later Prado. (Anyone want to swap?)
Make up some attachment brackets and pipework....
Cut hole in bonnet and graft in Bighorn scoop.

At this stage looks like I have enough room, but time will tell.

Then it all done, easy eh?

Will document and post as I go.

Anything I have missed.

Cheers
Calvin

[kiwipete]

Bighorn scoop is bolt on so that'll make it easy. Doing the same to my Terrano with a bighorn 3.1 intercooler.

[tallsam66]

if you do a body lift will be much easier to do

[kbushnz]

My measuring puts me at a 150 mm gap between the rocker cover and the inner skin of the bonnet. (when bump trimmed off)

Have a small lift 30mm and don't want to go any higher.

Cheers
Calvin

[Ginzu8]

So any updates

[kbushnz]

Yeah, Update. Umm Errrr
Have shaved off the rocker cover and bonded on a plate. The factory inter cooled version is too expensive.
Purchased a fan to mount under it. First one was too big.
Second is right diameter but thick.
Sits a bit high but well see. May have to put fan on top and lower intercooler.
Just misses bonnet as it stands.

Couple of pics.





Just sorting out plumbing, some silicone elbows ordered and got to pick up some exhaust pipe.
Would like to do it in alloy, but don't have a welder for alloy.
So mild steel exhaust it will be.
Might get it cadi plated at work.

So its a slow process.... No hurry. Doing it all myself.

After its plumbed up I will need to sort out the throttle arrangement. (fly by wire)

Cheers
Calvin

[kbushnz]

More updates.
Made up some flanges, cut down some pipe.
Made up a stay.
Welder ran out of gas.. Going to have to tidy some up again.



Fitted scoop. Had to do a bit of trimming.




Looks the part. Will cut hole in bonnet later.

Will be making the Intercooler to inlet manifold from Fibre glass...
Cant get pipe work in, and don't have access to an alloy welder...so will put my fabrication skills to the test.
Will make a polystyrene duct, then glass it. Once its cure wash out the polystyrene with solvent.

Will work fine.

Calvin

[Ginzu8]

Nice work mate. Still thinking if its worth sourcing a later model prado with the top mount intercooler and piping for the 1kz.. wonder how much work that will be involved..Also do you think that you will need to reprogrram the ECU once the intercooler is done or is it not worth considering?

[jeremy]

Wow, I'm looking forward to seeing your fibreglass intake!

[kbushnz]

Nice work mate. Still thinking if its worth sourcing a later model prado with the top mount intercooler and piping for the 1kz.. ?

Wreckers want too much, most just sell the intercooler for $400 plus.
When you need the rocker cover, piping, longer throttle cables, newer throttle body etc etc.

To date:
$20.00 Bighorn intercooler.
$23.00 pipes
$30.00 Bighorn bonnet with scoop
$35.00 Fan

Plus some bits from the garage and time.

No plans to tweak fuel or ecu at this point.

Cheers
Calvin

[kbushnz]

Wow, I'm looking forward to seeing your fibreglass intake!

Nothing special, not like the Lexus one I made eh?

Just make a new plenum and bond it on the intake end.

Only need to hold at 16 to 20 psi

Factory ones can also be plastic....but crimped on.

Cheers
Calvin

[jeremy]

Nothing special, not like the Lexus one I made eh?

Haha, yup. We used to get lots of comments about the airbox before your sticker washed away.

[kbushnz]

I will have to get another sticker..and seal it on....

[kbushnz]

More photos / Update

Have cut hole in bonnet, the frames came loose so have been re bonded to bonnet skin once I had finished cutting.



With the bonnet closed you can see it is rather close.
About 10mm.... May have to drop down the intercooler, but this will mean my fan may not fit.

You will notice that the old water washer nozzles are covered by the bighorn scoop.
I have relocated these back and out a bit.
Then I will adjust the nozzle aim. (the nozzles can be moved by putting a needle down the hole and adjusting the aim, they are a ball in a socket so can move)

Will run it fanless to start with and check for bonnet rub.



Looks good with the bighorn scoop.



Here is the duct I am making from Fibreglass... It has to do a wicked turn to get it from the factory manifold to the intercooler.

When I get a chance I will look into making a new end for the intercooler and having it exit straight into intake manifold.



Its a polystyrene shape wrapped in layers of fibreglass and resin, This is only with two layers as its a handful to add more. Will sand smooth and add more until I get my desired thickness.
Then wash out polystyrene with solvent.

Working on the throttle body / cable setup. Would be easy with one cable but mine has two.
Found a good spot for it behind air cleaner, just need to make up a bracket and re route the cables.

Oh and cut and splice in a longer TPS harness.

Amazing what you can do when you are home with the flu...

Calvin

Hopefully next week I can get her fired up again.

[kbushnz]

Second to last update until I turn the key.

Throttle body moved and brackets installed.
Cables routed nice and smooth and away from heat.
Kept original throttle body at this stage just in-case I need to go back to factory. Will source another one and cut it down later.



Here it is a it closer.



Calvin

[kbushnz]

Well I finally finished the fibreglass duct last night at work.



Painted nice and black to match the rest.





Just need to wait for the adhesive to cure (bonded duct to intercooler.

Then clamp up other end and turn the key.

Cheers
Calvin

[Ginzu8]

Nice work mate..

[IcedJohnno]

Hey Calvin
Looks great. Very keen to hear how it goes.

Some argue that the throttle butterfly is not needed. I see you are bothering with it.

What have or are you doing to re-rigidify the bonnet? Mine flexes enough without any of the bracing removed! A mate's is badly pushed in from a deep submarine dive at the start of a water crossing

Also how do you get under the sound prooofing without buggering up those stupid little spastic plastic retainers?
The couple of times I have attempted to see what's going on with the stiffeners, I keep breaking them, so have given up.

[kbushnz]

Some argue that the throttle butterfly is not needed. I see you are bothering with it.

No butterfly, removed it ages ago before this mod. Biggest difference was on shut down... run on abit.
My throttle is now remote... not on engine at all.

Bonnet has had stiffeners removed in area of scoop. Scoop is hopefully stiff enough to take load. If not I have bighorn bonnet and I will remove cutout and weld it in mine.. Time will tell.

The remaining stiffeners are bonded to the bonnet skin, I found all mine were unstuck... So a good sqwert of silicone fixed that.

I have no underbonnet sound stuff, was gone when I got it.
Its a waste of time for an off road truck. Always getting wet, then it falls apart. The plastic buttons go hard after a while and just fall apart when you try to remove them. You can get new ones at Supercheap or a panel beater.

Calvin

[kbushnz]

Waaahooo shes alive !.
Started first pop, I love these electronic fuel pumps.
Idles strong.
No funny leaks and sounds.
Taken for a spin around the block.
Not hitting previous boost on max acceleration.
Only down 1/2 to 1 psi. Not a big drop accross the intercooler.
EGT temps have dropped, used to easily hit high 600's up hills now down in high 500's to low 600's (giving it the boot)
Have wired in some thrmocouples under the hood (borrowed temperature logger from work)
Monitoring induction air temps...
Intercooler inlet and outlet. Probes on casting will have some temp lag but dont want to put probes into air stream.
Outside air temp in bonnet scoop and air temp exiting intercooler fins.
Also will show what temps the engine bay gets to..
Plan is to map it all on a 36 k trip into work this avo and a trip home.
Should give me ideas on how much its cooling induction air and speeds.... See how slow you can go before the intercooler stops working and a fan should be used.

Intercooler is not hitting bonnet.. But offroad will be the big test when the motor is all torqued up.

So far I have a big smile on my dial.

No plans to tweak fuel or boost yet. But not ruling it out.

Calvin

[SamLogan]

Hey i like your setup with the butterfly. I have a surf and need it for the tps. I see you said you removed it. Did it work how it was?

Cheers
Sam

[kbushnz]

Hi Sam

Yes the butterfly has gone (before moving throttle body from the intake manifold) and it reved a little easier off the mark.

In reality you dont need the throttle body on the engine on the 1KZTE.
I have removed mine and relocated it.

You still need the TPS for the ECU and its easier to leave it on the throttle body have it work like factory.

See my pics to get the idea.

Another guy here has posted his intercooler setup in a surf and has made a new Throttle / TPS unit.

A mechanical pump has the throttle linkages going to it directly. Again no need for a butterfly.

Will add an update during the day tomorrow. When I have read the data loggers...

But EGTs are definatly alot lower than before.

Calvin

[SamLogan]

Thanks for that. I think i might do the same as you and move it somewhere else because it will give me more room and it will also mean that i can protect the tps a bit better by maybe mounting it in a plastic case of some sort. i have already ruined 1 with water. What did you do with your EGR and all the VSV crap that is attached to the engine. As i am soon to be going down the mechanical pump path i won't be needing much of the electronics bar the TPS for the auto.

Cheers
Sam

[kbushnz]

Well did a run to and from work last night.
Interesting results.
Lots of data but I will keep it simple.

Cold air into scoop only starts working well at 40 ish kph.
At 20kph it was cooling...Any slower and the temps start rising.
Fan required for slow speed stuff (off road)

When travelling at 100kph, boost was 9 to 10 psi, EGT temps ranged from 450 to 520 C depending on slight hills on motorway.
Air from turbo was at its peek at 65C.....
So this is the time when the motor is stressed the most !..
Air post intercooler was 35C.

Did a run to the end of the North-western motorway. Got out popped bonnet and felt intercooler ends.
It was surprising to feel the difference.
Exit end was very cold to touch, in end was rather warm....

Slow speed at 50 - 60kph EGTs in low 300's.
Boost was 3 to 4 psi Not working hard.
Turbo exit temp in the 40's and exit in the 30's.
About 10C spread.

High speed stuff spread was as much as 25 - 30C.

Going to move my temp probes off the alloy casting and onto the pipework exiting the turbo and entering the intake to see if they show similar results.

I would really like to put probes in air stream to get real figures.

Conclusion thus far.....It makes a huge difference at high speeds. High loads.
Normal driving shows a good drop in EGT's which is what I was after.. But also offers room to tweak it up for POWER!!! Arg ARg ARg.

Low speed stuff is debatable but will play in Woodhill on Sunday.

Cheers

Calvin

[kbushnz]

Have put temp probes into air stream.
Drilled little hole in my fiberglass duct and used a factory pressure connection in the intercooler for the hot end.
Interesting results.

Once it has been heat soaked....

During acceleration on almost full boost, and not pushing her over the top. Hot end will climb to 80C plus FAST.
Cold end will start off a cool 35 then slowly climb to 45 ish.
As soon as you button off Hot end temps drop dramatically to 45 50 ish and cold end will drop slowly back to 30 35C.
This is during the cruise at 100 kph.

Around town normal acceleration, Hot end will climb to 65 70C.
And cold end will run between 30 35C.

Once cruising at 50kph - 60 kph, temps settle down to a 10C difference.

Naturally hot end temps lift when accelerating to modulate speed or climbing an incline. But the cold end will stay at the 30 to 35 during this time. So the intercooler is soaking up the heat...

So it works !!

During summer I expect to see the temps rise according to outside temps being warmer.

Sitting at the lights for extended times you still get a 5 to 10C drop.... across the intercooler.

So summary for this intercooler...

During acceleration I can expect a 30 to 40C difference in temps.

During cruise around town I can expect a 10 to 15C difference .

During highway cruise I can expect a 20 to 25C difference.

Now its time to test it in an off road situation on Sunday... In Woodhill....

Calvin

[Andrew1706]

That's some pretty cool (ba-dum-tish) info!

[kbushnz]

What did you do with your EGR and all the VSV crap that is attached to the engine.

EGR and all that other stuff went years ago...
One of the first mods I did..

Then I cracked a head...So while it was all apart, I did a nice job of removing the pipework and blanking off...

Calvin

[kbushnz]

That's some pretty cool (ba-dum-tish) info!

Thanks, I have been looking at posts on all sorts of forums.
They all say "It pulls better or runs cooler" but have no real time info.

So as I have the tools to do it....I have posted it for all to see...

Tomorrows trip will see what I get off road with no fan.

Then next trip with a fan..Etc etc

Then I might play with boost and fuel.

Has a little flat spot I would like to remove....

Calvin

[kbushnz]

Well finally home from Woodhill... Last punter broke his truck and was on his own.
Took a wee while to find him and tow him out. Quite spooky driving in the dark.

Now for the data...
Temps at slow speed off road stuff.

The intercooler turned into an interheater.
Temps basically all evened out at about 45C
Only when I got a steady run did it start to drop..
But that wasn't often.
Most of the time you are on boost climbing hills or spinning tyres.
And there is no airflow into the cooler to get rid of any extra heat.
And when you stop to wait for the guy in-front, it just heat soaks.

So conclusion... A top mount air to air intercooler with no fan is of no good off road. Which is what I guessed.

Next step, wack on that fan !.

Calvin

[meatc]

Cool that yiu have the tools to do the tests to back up the theory, make sfor interesting reading. Also confirms that I was right to get a water to air intercooler to go on my race truck for when the super charger goes on this week. Be interesting to see how much difference a fan is going to make on yours.