Thanks so much for the feedback - I will be ordering soon!
Has it been pretty noticeable with lower heat and power improvements?
kzj78 Turbo exit size (1 Viewer)
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Thanks so much for the feedback - I will be ordering soon!
Has it been pretty noticeable with lower heat and power improvements?
GTSSportCoupe
2LTE abuser
My understanding is the larger the dump pipe the better. Pressure directly after the turbine will reduce the turbo efficiency.
Regarding the flow issue, that does definitely apply, but more to the exhaust system then the dump pipe. So don't go too large with the exhaust. Considering a 3.0l diesel moves about the same amount of air as a 2.0 gas engine, I'd think that a mandrel bent 2.5" exhaust would be fine (wth a free flowing muffler).
Regarding the flow issue, that does definitely apply, but more to the exhaust system then the dump pipe. So don't go too large with the exhaust. Considering a 3.0l diesel moves about the same amount of air as a 2.0 gas engine, I'd think that a mandrel bent 2.5" exhaust would be fine (wth a free flowing muffler).
This makes sense. Anybody else have any feedback on the issue? I have decided to go with the 3” dump pipe but have not yet decided on the exhaust.
Heres what ive recently made for my LJ78 with the 2lte, think the systems slightly different due to where the turbo sits, however some points that may cross over to what your doing
I used the 2.5", this worked perfect for the opening size of the CT20 turbo flange, from what i can tell a 3" would overhang the sides of the plate possibly.
I welded mine up to the factory 2" pipes for now as i want to test each mod and see the changes each makes (plus im not ready to drop $500+- on a full system just yet)
I found the change of dump pipe didn't make heaps of difference regarding etg's with the standard pipes, however it has given the truck more guts. In the photo you can see the standard dump next to mine. factory dump is pretty narrow inside those bends also..
If your making one i would buy the turbo flange to suit your turbo first and measure what pipe will work best with it potentially.
I used the 2.5", this worked perfect for the opening size of the CT20 turbo flange, from what i can tell a 3" would overhang the sides of the plate possibly.
I welded mine up to the factory 2" pipes for now as i want to test each mod and see the changes each makes (plus im not ready to drop $500+- on a full system just yet)
I found the change of dump pipe didn't make heaps of difference regarding etg's with the standard pipes, however it has given the truck more guts. In the photo you can see the standard dump next to mine. factory dump is pretty narrow inside those bends also..
If your making one i would buy the turbo flange to suit your turbo first and measure what pipe will work best with it potentially.
Pretty dramatic difference!
Getting ready to make a purchase from Kaiapoi folks and want to make 100% sure I’m ordering the right size...2.5 or 3” for a 1993 KZJ78W/1KZTE engine? Thank you!
There isn’t a “right” answer, this is based on your preference. Some will site needing back pressure and go with 2.5, or just that 2.5 is plenty big for this little engine. Others will go with 3”, because the more efficiently you can remove exhaust gas from the engine, the better. Read and come to your own conclusion. I went with 3” when I had mine and was happy with my decision.
Thank you, Lenny. Just am trying to get a consensus because I don’t plan on towing or doing serious off roading with my Prado but the places I can go back to in the U.S., Nevada, Arizon or South Georgia are pretty hot, not to mention availability of replacement heads will be “nill-to-none” and I want to make sure I do it right when it comes to preventing head cracks.
Seemed like a no-brainer to me - the bigger the better for removing exhaust heat from the engine. There may be more experienced people that will say otherwise, but to me, this seems pretty straightforward.
Sounds awesome! Gonna go 3”
@kbushnz thanks for sharing the photos—very helpful to see.
I asked this on another ih8mud discussion—but did you end up putting any type of heat shield / radiant barrier between the larger dump pipe and cab fire wall (like the stock setup has)? Or did you just run without any additional shield?
Hi Yah, I didn't add any extra heat shielding. There was a nice gap between the pipe and the fire wall. Also the firewall still had its insulation shield intact. If you could squeeze one in , it wouldn't hurt or wrap it...
Did you end up getting a dump pipe and exhaust? If so, where’d you get the exhaust done
I went to Kaiapoi Repowers in New Zealand. Just got the dump tube for now. I have attempted to ask them if they carry the entire exhaust system from the dump but unfortunately they don’t. I’d have it done here in Okinawa if I could find a reliable exhaust technician but the only person that I have heard of is swamped with work until September and he charges a pretty penny but then he does very good work. So, I’m just to do what I can to mitigate the issue; maintain the cooling system, use OEM Toyota coolant at a 60% coolant/40% distilled water mix. May upgrade to 10 bladed fan, re-service fan fluid…
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Sooooo…what IS the answer? 65mm? What about the actual exhaust? I have my 3” down pipe and am thinking of pulling the trigger on a 70mm (2.75”) Fujitsubo exhaust for my KZJ78/KZTE, will this work? Thanks!
Hello fellow 1KZ owners! My name is Todd. I use to work for an importer in Oregon. I’ve been wanting to upgrade the stock turbo dump pipe for our CT12B turbo. I tried looking online for something like this with no luck here in the states. I decided to draw and laser cut the turbo flange out of 1/2” mild steel, (Made in the USA) ready to be welded for your a DIY dump pipe.
This turbo dump pipe flange should fit any Surf, Hi-ace, Hilux, Prado with 1KZ engine and CT12B turbo.
If you have any interest in ordering one please head over to my eBay store.
Please message me with any additional questions!
Thanks for reading!
-Todd
This turbo dump pipe flange should fit any Surf, Hi-ace, Hilux, Prado with 1KZ engine and CT12B turbo.
If you have any interest in ordering one please head over to my eBay store.
Please message me with any additional questions!
Thanks for reading!
-Todd
Hey Todd, is this the new listing? Looking at possibly making a dump pipe for my KZJ78, if I can’t get one from Krae. Thanks.
Toyota 1KZ Ct12b Turbo Dump Pipe Flange | eBay
Toyota 1KZ Ct12b Turbo Dump Pipe Flange. Condition is New. Shipped with USPS Ground Advantage.
www.ebay.com
