KZJ78 Intercooler and other Upgrades

[peter_Kzj78]

hi guys,

after some time of just thinking and making plans I finished a lot of work on my 1996 KZJ78 with 1KZ-TE and A343F
This forum and its members have been much inspiring, thanks a lot guys. While here in Europe everyone is just crazy about the 80series and HZJ models, I´m still a huge fan of the KZJ7.

I recently changed the gear set from 4.33 to 4.88 which makes quite a nice on 33" tyres. I haven´t seen much of a difference in the milage honestly.
at the same time I swapped the axle hubs to LJ73 post 1990 model which came with factory manual free wheeling hubs. my e-locking hubs died almost instantly, then changed to manual hubs using spacers but then the bolts grew by 1,5 cm´s and I managed to crack them everytime I was out playing. same time I swapped the brass bushings and put in new seals in and out. quite a greasy job but sure you know it too well.
I recently fitted a side pipe exhaust because I finally managed to crack my exhaust in pieces when reversing uphill. so instead of starting my 2,5" exhaust and dump pipe project nice and slow I had to drop in that sidepipe first. sounds quite nice and perfect fit.
dump pipe is to follow, just ordered the flange for the turbo. this country gets more and more bureaucratic I tell you and it´s very hard to find anybody to do such a small job. shall get it next week... 80 EURO a piece you won´t believe it but true...

Here are some pictures of my IC project. I finally purchased a full set which was supposed to fit a 1KZ-TE HILUX as they run in OZ. I had to find out that not only the rocker cover hump was in the way but also the valve throttle body builds too high and due to our strict regulations I cannot just drop that part... when doing my research I found that the factory intercooled version also uses a different intake manifold which builds flat and the throttle body sits horizontal on it instead of tilted some 30 degrees to the left.
out of question that buying those parts would mean facing bankrupcy. Toyota is asking about 1000 EURO for intake manifold and throttle body. hahaha. if somebody is interested in how it would look I do have a screen shot.

so...as my front is crowded with AC radiator, Oil radiator for the A343F and AC pipes no chance to go front mount without huge efforts.
I´ve seen other KZJ with AC where the pipes run differently, well not mine...

after some fiddling I found that the best space under the bonnet without lifting the body is parallel to the rocker cover, see for yourself.

Does anybody know the temperature of intake air after turbo? may that be around 140 Celsius? Well, actually I can still touch the surface of the IC after a ride, but you wont rest your hand there. must be around 60 - 70 C I would guess.
I am planning to do a custom scoop with two air channels so that front and back get a fair portion of wind. at the moment I have the scoop as used on HIlux, came with kit.

I got an adapter for the throttle body mady from stainless steel which even gave the opportunity to mount the accelerator and kick down cable. nice part.

here we go, cheers and again thanks for the inspiration!

[peter_Kzj78]

another one...the core is slightly wider than the factory IC but 3" thickness.
I have run a hose from wastegate to the adapter for the throttle body to receive pressure input from there instead of at the turbo outlet.

Finally I have changed the Fuel Pump setting by doing an extra 1/4 turn. At this setting there is absolutely no smoke at no time, not after start and not during full throttle. I guess there is some potential left but first I need to pass my road worthyness test in september.

that was pretty much it

[peter_Kzj78]

and that´s the truck

[peter_Kzj78]

[youtube]https://www.youtube.com/watch?v=Q-T4MREKRj8[/youtube]

https://www.youtube.com/watch?v=Q-T4MREKRj8

[kbushnz]

Nice truck and some good work going on there. Great to see people giving it a go.
Intercooler looks like it would work fine for normal driving but slow off road would get heated up by the turbo below it. Suggest a heat shield and a fan if it would fit?

[peter_Kzj78]

Nice truck and some good work going on there. Great to see people giving it a go.
Intercooler looks like it would work fine for normal driving but slow off road would get heated up by the turbo below it. Suggest a heat shield and a fan if it would fit?

Thanks Calvin!
You are right and I´m also worried about the heat in that compartment. the engine bay is so cramped and the IC basically rests on the AC tubes and next to it is the Webasto heater. Nevertheless I plan to do something like heat shield and fan. for the heat shield I´m not sure how to do it best. I don´t dare to cover the heat shield of the turbo with another layer of insulation as this metal sheet has some cooling slits. would this matter? regarding the fan I´ve seen a lot on Ebay like 8" diameter but I would really need something more compact as I can´t put another 3" layer on the IC itself. Any ideas?
cheers
peter

[peter_Kzj78]

so, I followed Calvin´s advice and gave it another shot...

space is too tight for a fan underneath the IC so I decided to put in an additional heatshield just between the heat shield of the turbo (there are cooling slits right up to the IC ) and the IC itself. would say there is a clearance of about 2,5 " between the two.

was thinking how to do that and was searching the garage for some tin sheet when I found the lid of an old Wok pan
as I like the recycling idea in general I just started to cut it out and bend it into shape an screwed it to the cylinder head.

as there is a nice airstream from the visco fan I finally decided to place some rubber mat from on top of the fan shroud to the lower side of the IC. this way there might be some air stream to blow away the hot air between the to metal sheets. or not. we will see. trial and error but better than before I guess. hope it won´t harm the turbo ?
[/attachment]

lid of wok pan :-)

[Jerry]

How do you find the 4.88's with smaller road tyres? ie 31" (I run 32" ones for my road set)
I have a turbo dump pipe and 2.5in exhaust which helps with power, have a factory 90 series prado intercooler kit to drop in it.

[peter_Kzj78]

How do you find the 4.88's with smaller road tyres? ie 31" (I run 32" ones for my road set)
I have a turbo dump pipe and 2.5in exhaust which helps with power, have a factory 90 series prado intercooler kit to drop in it.

Honestly I didn't try smaller ones. I had 31" when I bought the truck on the 4.33 ratio and found that it was quite a good setup. In sharp bends easy to loose traction and burn some rubber
But looked a bid undersized for the truck. I soon changed to 33" and used that setup for 3 yrs on 4.33. Combined with the auto box too fast crawling downhill (almost twice as fast as an 80series on 285 75 16). On the road too slow when attacking a lorry at 80km/h.

I'm glad I did it. Was thinking 32" AT as I just get MTs in 33" for the 15" rims.

Dump pipe is next

So you're about to put in the IC?
I was looking for the 90series piece forever. No chance over here.
but recently found that they use a different intake manifold as well. At least the newer version 120prado or hilux with 1KZ in OZ.

[Jerry]

No Limit tuning do an ECU chip for $200 (Germany I think)
viewtopic.php?f=46&t=31634&p=405675&hil ... ip#p405675

The 90 is badged as a "Landcruiser Amazon" in the UK

[Jerry]

[Jerry]

[peter_Kzj78]

Just awesome, Mate!

Beautiful Pictures. It takes me a 7hrs drive before getting to places like that without being prosecuted

Thx for the chip box. Didnt see them before. Germany, cool!
I bought one from Italy which turned out to be for 1KZ Hilux - Australian version with Bosch VP44 fuel pump instead of Denso. Waiting for exchange since April

Btw in UK the 90 Prado runs by "Colorado" , 80 and 100 are "Amazon"

But no limit tuning seems quite reasonable, will definetly keep it in mind.

Thx a lot

Anyone using the no limit box on his 1KZ TE?

[peter_Kzj78]

so....did like 4000 km now with the IC fitted and still glad I did it. good torque and accelaration.
put in an 8" fan below the IC now to support it at low speeds. as it´s autumn now so we are having temperatures at below 10 celsius, summer will tell how it works.

[peter_Kzj78]

here is a little update from my side which is long due, sorry for being late.

what did I do / find during the past months, well, almost a year now.

I have been to the Sahara desert in April, Tunisia. Great trip, finally got there after some years of planning. the Tunisian desert is said to be the worst sand desert, dunes are low and come one by one. there is no resting. we´ve done 350km in 6 days with very little tracks. this means you go at it all the time.
air temperatures are aroung 15 - 20 Celsius, while sun is burning down like 30 - 40 C. reminds me a bit of boating or skiing in spring time.
the setup was still reliable and strong. didn´t push the pump too far, runs nicely, turbo boost still factory setting.

compared to D4D version with turbo chip (200 HP) and Nissan Patrol 3.0 td (Y61) it has much sweater torque from low revs altough being 20 - 50 HP short on them. highway ofcourse they burn me totally.


what I did since then:

finally upgraded to a tuning box that works! it is an Austrian product which was sold since the 1990´s. when it was introduced it was pretty expensive >1000Euro. they sit on some stock and I got it for less than 400 now.
needed to be connected to the ECU in the glove compartment. not too bad, some soldering, 1 hour work.
the default setting on the box is + 50Nm + 22 HP, there are 4 more steps to push it up another 2 HP each step. didn´t go there yet as still not modified the boost.
it gives noticable power. my uphill climb to my home is done now at 70 km/h instead of 55 when pushed. it also revs nicely beyond the 3000 rpm mark. still the Auto gearbox kills some of the fun.

I played around with a dump pipe for a while. still have flanges here but could not finish. my road test came in between and I needed to replace the down pipe since it was quite done on the flex part. changed it to 3" which brought some more hassle. the flex part is now only 10cm which leads to lot of vibes in low revs. welding seem broke in Tunisia at the turbo flange. loud and no power. there is something about back pressure...will try to give that some attention during winter season.

I installed an additional radiator for engine oil which is basically a 60cm pipe with cooling fins which I managed to fit in front of the AC radiator. needed a sandwich plate for the oil filter and some custom hoses which I got done at a local hydraulics shop. seems to be a nice setup, no temperature problems anymore hopefully.

I connected a turbo gauge. turbine is doing good but with noticable whistle by now. maybe the larger exhaust? EGT gauge is set up, sensor needs to be fitted to the exhaust manifold which I plan for winter - plan to having the turbo rebuilt with 15% larger compressor wheel since it needs some attention anyways. if nothing else comes inbetween and this may well be the gear box....have some odd vibration when stopping the car in D. feels like you are stalling a manual shifted car when not pressing clutch at stopping. when accelerating in the higher revs in 3rd gear it seems to have some slip. enginge revs up to lets say 3000 rpm and then clutch engages and rev drop to 2500 - without OD engaged. feels like a worn clutch on a manual car. probably need a seperate thread on it.

had to chance rear stabilizer links and bushes, did an extension to the links. will have to see how they work offroad yet.

that was pretty much it. love the truck. absolutely.
pics shall follow

cheers
Peter

[peter_Kzj78]

so, here are some pics

[peter_Kzj78]

had to exchange the fuel primer pump too.

probably the third time that I have that job done because of leaking membrane.
no I just went for an aftermarket pump used on dumpers or tractors.
goes strong and hopefully will last. if not, membranes are exchangeable. pump was 1/3 of toyo part. ok, has no heater built in but I don´t really use it in winter time.

[Smurf]

Interesting write ups Peter, Thanks for taking the time to update your thread. I enjoy it.

[peter_Kzj78]

hi guys,

since I only wired my turbo boost gauge recently I found the pressure not going beyond 0,6 bar (8,7psi) while I think 0,7 (10,15psi) would be stock.
on my latest trip my travel buddies told me about the eventual blue smoke when under pressure. honestly it feels like if the turbo has had it´s better times already. we went up a very steep incline, I would guess about 30 degrees for about 300 - 400m , low gear 1st and I was pedal to metal and afraid I wouldn´t make it while the little 2L-T had no issue but black smoke of course.
mine was black and kind of blue i was told. while i still think the truck goes quite well considering the fun breaking auto transmission and giving me a good reserve to overtake trucks at 80 spooling up to110km/h easily I though find it prone to stalling uphill when the turbo is not delivering.
so, having said this I searched for my old turbo which was quite worn and rattling and took it to a turbo shop. found that the waste gate exit hat a crack as well and the turbine was grinding on the insides. anyways they said it´s a solid basis for revamp and I decided to go for a bigger wheel which is 4-5mm bigger in diameter cnc cut etc., the upgrade vs revamp is only about 200 euro plus so why not whilest at it? totals to 650.
have to wait for another week until i get it back. they promise the same boost at lower turbo revs plus the reserve of extra air at max. revs.
will set it to 0,9 - 1.0 bar then.
it will take me some time to install the turbo as autumn has arrived quickly and I need to find time and space inside my cramped garage.

keep ya posted

[peter_Kzj78]

refurbished turbo is here.
they threw in a bigger compressor wheel, the latter plus 5mm in diameter... altough i said please don´t go too far.
will have to try I guess.

I will install it on friday and report back

[peter_Kzj78]

finally the turbo is installed
in combination with chip tuning box at medium level it fires up to 4900 revs/min which was 4500 before both at factory boost of 0,7bar.
I don´t feel any delay in spooling up, bottom torque still good.
before playing with boost and chip set I need to refresh the road test which is quite strict here...

keep you posted