[Macgyver]

Lets hope it wont burn up.

Did you blow torch a small piece to test it ?

 

[pboglio]

Good point Mac. It'll get tested on the vehicle but I'll be carrying a fire extinguisher from now on for sure for many other reasons.
Elbow is rated 60*F-450*F (ASTM E84 25/50 for Flame and Smoke) and the woven fiberglass is good to about 1100*F ignition temps.

Keep in mind my setup also has full ceramic coating of the CHRA and turbine/manifold/downpipe/testpipe. Cerakote supposedly have tested the ceramic coating and skin temps don't run higher than 915*F with an EGT of 1690*F based on their lab testing.

The setup doesn't have the turbine heatshield or downpipe shields in place yet, working on it.

 

[squirtbrnr]

with an EGT of 1690*F based on their lab testing.

I want to see your juke exhaust glowing red hot! Haha

 

[pboglio]

I want to see your juke exhaust glowing red hot! Haha

I'll do my best....lol. If it goes up in a ball of fire at least it'll be glorious, you guys get first dibs on the video.

Think I've settled on a downpipe/testpipe heat shielding solution that I can accept. Definitely not going to pipe "wrap" the downpipes as this causes pipe oxidation and overheating. Heat-Shield Products makes a very well engineered aftermarket exhaust pipe shielding. OE designs are probably better but require some serious tooling to form the steel shields. To compare, I've reviewed some of my stock downpipe/midpipe OEM designs (Juke/EVO/STi) and sure enough it's just a steel clamshell over an exposed fiberglass matting so the concept is sound.

You can see that these particular Heat Shield Armor shields have their Biocool insulator matting. However, there is a pre-determined "gap" in the shield that is required to prevent meltdown. It's specifically designed for the pipe diameter you specifiy and leaves about 1/4 of the pipe diameter exposed for heat release to prevent meltdown. I'm running full 304 stainless downpipe so it can easily handle the temp increase even with the ceramic coating. I also like the hook/wire design as it prevents from crushing the shielding though it's not as clean/pretty as the stainless steel zip ties. They do offer 304 SS springs to attach the shield as well if you want to go full-out. Common problem is crushing/wrinkling the shields but you can see in the link if it's installed correctly the shields end up looking fairly crisp and non-wrinkled.

Motoiq have a really good review on a Dodge Viper and they "pie" cut the shielding to form around bends and use the stainless zip ties and it looks immaculate. They kind of make fun of the disco style "gold" foils which are nowhere near as effective.

Project Viper GTS: Part 7 - HeatShield Products - Page 6 of 8 - MotoIQ

Wrapping a bend is a little more complex and requires a few pie cuts to get full coverage. With some patience, the installation looks fantastic. We also wrapped the 3”…

motoiq.com

I'll be running a 2.5" diameter x 12" section and then custom cutting another to about 8" length. The stock OE upper downpipe heatshield is going to get slightly modified, removing the riveted ear portion, and then double-ceramic coated and I'm putting that back on as well since it'll be tough to form something around that bend without it looking like an arts/crafts project.

Turbine heatshield I've designed a custom version on Solidworks and getting quotes for laser cutting and CNC press brake forming.

Heatshield Armor™ Pipe Shield

Exhaust pipe heat shield - Heatshield Armor™ Pipe Shield

www.heatshieldproducts.com

 

[pboglio]

Just received my Heatshield Armor kit (12" x 36" x 1/2") for the downpipe/testpipe heat shielding. Purchased the rivet hook/wire kit(s) for securing the heatshield and keeping it tight without crushing it. Also purchased some 5/16" wide stainless steel zip ties as an alternative for mounting. A steel hole punch kit was added for punching clean/crimped holes thru the shields for various bosses & 02 bungs. Final price w/shipping came out to $198 from Summit Racing.

This shielding is rated to 1800*F continuous/2200*F intermittant & the insulation sits directly onto the tube/pipe. For those that might wonder if using header wrap would work better, no it won't based on their own testing. There is a lot of debate over header wraps but I won't touch that crap. The Heatshield Armor has a similar texture to the OEM aluminum heatshielding but a little bit thinner at .008-.010" though it's still quite rigid it still can be easily formed over tube/pipe. It's recommended to install with a 1-2" gap running lengthwise along the tube/pipe for heat dissipation and preferably towards the ground/road.

There's still some work in tracing out a profile template onto 22"x28" poster board and creating the flat blank. I laid out a trial fitment with some aluminum foil to see where the material will wrinkle and require some relief cuts.

 

[pboglio]

Upper downpipe shielding installed. It took awhile to cut template after template to make sure it fit right. The shielding is about 1/2" thick and this causes the material to shrink when you wrap it so you lose material length. So in retrospect you need to cut an additional 1" to account for the bend wrap or shrink. Then another 1" for a 0.5" wide 90* folder over on each edge to seal up the insulation as recommended.

I know it looks like terrible but the gap in the shielding is there on purpose to prevent the downpipe from melting down. Heatshield Products recommended a 2-3" gap on turbocharged engines and it's right about 2-2.25" on the 2.5" downpipe so I'm right there. You can see I'm aiming the gap back towards the exhaust manifold heatshield for the upper wrap since there is no other safe direction to orient the gap. The 2nd piece for the lower downpipe the gap will be rotated towards the ground, this is why I split the shielding in (2) pieces. I left some extra material for that lower downpipe shield to wrap over the top of the 1st piece to finish it off. Additionally, every edge has to be folded either 90* or a hem edge like I did near the downpipe flange. This is to prevent water from entering the insulation

Overall a very difficult material to work with but if you take your time and pie cut the flat blank and add additional length to trim and fold back it's not too bad. There are always going to be some wrinkles but because the material is heavily dimpled it's kinda stiff as well. You kinda have to form it and bend it into position and work it into place. The stainless zip ties are really the only way to go as they are 5/16" wide and don't crush the shielding when pulled tight.

 

[pboglio]

Finally have the remaining DP wrapped with the Armor shield. Pics show the paper template I used to overlay and trim. I'm adding a total of 8" width to wrap around a 2.5" tube, which gives 0.5" per side for forming up the 90*, plus some for the bend allowance as the shielding adds 1.0" to the tube O.D. and requires bend compensation.

What saved a lot of effort was punching a 1.25" diameter hole around the 02 sensor bung on the heatshield, this allows me some lateral play to adjust things and worked great as I didn't have to fight the heatshield to fit it up properly. Have to be a little bit delicate with it but if the template is cut correctly you just sort of wrap it around & the aluminum shielding bends permanently and holds shape. Once everything fits up nicely I wipe the entire downpipe down with alcohol to remove any oil to prevent an ignition point. The (2) separate shield pieces are needed so that I can alternate the gaps to face inwards & downwards to keep the heat away from critical components. This heatshield is impossible to get perfect but you kind of work it and once it looks all good the zip ties cinch everything down nice and neat. The lower shield gap isn't shown but again it's 2" wide facing the ground.

Took about 2-3 hours to complete. I need to add another (2-3) stainless zip ties to complete then I'm done with that. The testpipe I'll have to buy some more heatshield & zip ties but for now it won't be high priority as it can go on later and being a straight piece of pipe easy to wrap.

Remaining stuff:
So that was the tedious stuff. I'm now down to simply bolting on the various 02 sensors, knock sensor, spark plugs, ignition coils, valve cover bolts/gasket, etc. Making my life simple I'm going to purchase the OE Nissan engine hoist brackets (front & rear) and mount with high strength bolts. This'll make it easier to service the engine in the future if the lift brackets are already in place. I'm fully expecting to waste another CVT transmission so making serviceability easier is going to reduce future headaches.

Before I put the engine on the hoist I'll have to switch my attention to the CVT as it needs a few upgraded components installed before I can mate everything to the engine. I've been putting that task off since it requires a clean/dust free environment and some space to lay out the guts of the CVT transmission. Those upgrades will become critical once I start laying down some respectable torque. I'm going to need everything in the CVT as bulletproof as I can get it to be and as mentioned before I'm having to go back into the transmission again to make that happen.

 

[nsal]

I think before I spent all that I would find a 2006 Corvette for about 20k with 60k miles and have a 400hp beast with no mods...

 

[Ausjuk33]

I think before I spent all that I would find a 2006 Corvette for about 20k with 60k miles and have a 400hp beast with no mods...

Yeah, but then you're the same as every other corvette driver. Too boring. Appreciate the level of awesome that will be his juke. He could open a nissan special vehicle division and build them by hand for rich paying enthusiasts. 🙆‍♂️🙆‍♂️. How they should be put together.

 

[pboglio]

I think before I spent all that I would find a 2006 Corvette for about 20k with 60k miles and have a 400hp beast with no mods...

That is absolutely a fair point. For 99% of people, I agree with you. I already own a ~400 h.p. EVO X which'll soon get closer to 500 h.p. probably next year so I'm good on horsepower and that vehicle was purchased because it is dead reliable at those power levels. Still, I'd often grab the keys to the Juke first even though it's a dorky looking car and get's zero looks it's the more "fun" car to drive. I can't describe it because by every metric on earth the EVO is a "better" car and would absolutely crush it. So a 400 h.p. Corvette wouldn't do it for me even though they are reliable.

The main reason for this build is somewhat personal but I'll say the ~$25k I spent or will spend by the end of this year could be considered my Master's degree in Automotive engineering....hahaha. To really understand a car, you really have to build one to know and so that is an interesting challenge to undertake which is why folks do it I'd imagine. For context I was actually starting the road race/auto-x build on my STi and in the middle of pulling the failed EJ engine when the Juke also went down with a CVT failure. Keep in mind I'm also in parallel upgrading the EVO X all the while so I had a lot going on. So I had my options of (3) paths to take for a build: Juke, EVO X, WRX STi.

If you've never had a vehicle fail catastrophically on the highway/road I can tell you it's depressing, especially your daily driver. I got pretty good at coasting a vehicle after an engine or transmission failure right into a parking lot just because I had lot's of practice and that isn't something you want to get good at. When I had to physically push the Juke down the expressway shoulder when the CVT imploded that was the last straw.

Having had plenty of modded vehicles you come to the point of having to build it right cause eventually the same damned thing happens and it breaks every time. I'm still not sure I made the correct decision. The Juke will actually be my daily driver/beater as crazy as that sounds and my GF cannot even understand my reasoning. But when I say I'm going to do a thing, I'm usually good to my word. This is coming up on (4) years in September since I started the build but like I said whatever it takes it takes to finish it and at this point it'll get finished year end......knock on wood.

Long explanation for a short question but hopefully that makes some sense.

Yeah, but then you're the same as every other corvette driver. Too boring. Appreciate the level of awesome that will be his juke. He could open a nissan special vehicle division and build them by hand for rich paying enthusiasts. 🙆‍♂️🙆‍♂️. How they should be put together.

Never drove a vette but I assume they are impressive from what I hear. Thanks for the support. I'll have to keep an eye out for those rich folks with too much money on their hands...lol.

 

[Macgyver]

Mustangs. Corvettes. Dime a dozen.

Built or Fast Jukes. Very rare and they drive way better too.

 

[Ausjuk33]

That is absolutely a fair point. For 99% of people, I agree with you. I already own a ~400 h.p. EVO X which'll soon get closer to 500 h.p. probably next year so I'm good on horsepower and that vehicle was purchased because it is dead reliable at those power levels. Still, I'd often grab the keys to the Juke first even though it's a dorky looking car and get's zero looks it's the more "fun" car to drive. I can't describe it because by every metric on earth the EVO is a "better" car and would absolutely crush it. So a 400 h.p. Corvette wouldn't do it for me even though they are reliable.

The main reason for this build is somewhat personal but I'll say the ~$25k I spent or will spend by the end of this year could be considered my Master's degree in Automotive engineering....hahaha. To really understand a car, you really have to build one to know and so that is an interesting challenge to undertake which is why folks do it I'd imagine. For context I was actually starting the road race/auto-x build on my STi and in the middle of pulling the failed EJ engine when the Juke also went down with a CVT failure. Keep in mind I'm also in parallel upgrading the EVO X all the while so I had a lot going on. So I had my options of (3) paths to take for a build: Juke, EVO X, WRX STi.

If you've never had a vehicle fail catastrophically on the highway/road I can tell you it's depressing, especially your daily driver. I got pretty good at coasting a vehicle after an engine or transmission failure right into a parking lot just because I had lot's of practice and that isn't something you want to get good at. When I had to physically push the Juke down the expressway shoulder when the CVT imploded that was the last straw.

Having had plenty of modded vehicles you come to the point of having to build it right cause eventually the same damned thing happens and it breaks every time. I'm still not sure I made the correct decision. The Juke will actually be my daily driver/beater as crazy as that sounds and my GF cannot even understand my reasoning. But when I say I'm going to do a thing, I'm usually good to my word. This is coming up on (4) years in September since I started the build but like I said whatever it takes it takes to finish it and at this point it'll get finished year end......knock on wood.

Long explanation for a short question but hopefully that makes some sense.



Never drove a vette but I assume they are impressive from what I hear. Thanks for the support. I'll have to keep an eye out for those rich folks with too much money on their hands...lol.

U give me hope that one day i too will build something awesome again. Why, because we can. And its not the same as every other high hp car out there. Its special. 👍

 

[pboglio]

@Ausjuk33,

Yeah, build threads are always inspiring. Hopefully you can get back and start your favorite build when your ready.

Mustangs. Corvettes. Dime a dozen.

Built or Fast Jukes. Very rare and they drive way better too.

It's the short wheel base and small size & lightweight that make the Juke fun to drive IMHO. The AWD w/vectoring is kind of impressive for a CUV and what it does for cornering traction but the RS was also pretty sticky in the corners too. Can't wait until I lower it with some wider wheels/sticky tires and increase the track width. The newer cars are longer wheelbase & more stable but much heavier and not as fun. I'll try and explain this to folks and they'll never get it. This is why I'm a fan of the older STi as it feels like your getting into a WWII fighter cockpit and you can feel every pebble in the road and with a good set of sticky tires hear the rocks hit the fender well. Newer cars are more powerful and bigger but something get's lost in translation.

 

[Macgyver]

They are heavier. Safety. Just not as fun to drive.

 

[pboglio]

Going to talk about the Mamba 19T turbo here which is somewhat of a hated turbo.

16G Discussion:

Before it's mentioned that a 16g would crush a Mamba or whatever, please understand I've run (3-4) versions of the 16g over the last 30 years and currently do so on the EVO X. Also understand I've never paid more than $599 to $799 for a 16g brand new installed so anything Juke related isn't going to interest me though it has crossed my mind a couple years ago. Anything I've ever wanted to do or will ever do with a 16g I've already done. I've run ~404 w.h.p. on an EVO3-16g/7cm^2 @ 28 psi and ~ 340 w.h.p. @ 21 psi on my current EVO X 16g TD05H-152G6-12T daily driver. With the Cosworth cams, tubular manifold, and upgraded wastegate actuator the EVO X 16g should put down about 370-390 w.h.p. and I'll then retire that 16g turbo. Replacing it will be a much bigger TF06-07-18KX3RC factory Mitsubishi turbo upgrade good for about 460-480 w.h.p. None of those turbos are laggy by any stretch of the imagination thanks to the twin volute divided turbine & manifold and will hit full boost by 3500 rpm (16g) & 4,200 rpms (18K) respectively.

For the Juke in the future I'm looking at the Garett G25-550 with a .72 A/R turbine housing. I've always wanted to run a Garett turbo with ball bearing cartridge for the snappy response. It's overkill for a CVT but has rapid spool and good for about 400-425 w.h.p. @ 20-22 psi on a few 2.0L applications though it's been pushed much higher at higher boost. My Juke will run happily @ 14-16 psi on my daily tune.

Mamba 19T discussion:

Getting this out of the way 2J already ran 315 w.h.p. on a Mamba turbo. Typically these turbos put down 330-340 w.h.p. max depending on the application (i.e. Volvo, etc.) and that's a realistic number to shoot for. Not terrible for an $899 drop-in turbo. Now the billet 19T (6+6 style) compressor section on the Mamba are actually a pretty good compressor by themselves. The new billet style is actually rated by Mamba to 38 lb/min @ 14 psi and probably would push 40 lb/min choke flow. Also, Mamba have offered up the heavy duty TD04 thrust kit which solves the notorious TD04 bearing issues. The turbine wheel options also are decent especially the newer high flowing 9-blade TD04HL turbine. Twin 19T turbo Nissan GTRs are putting down 660-700 w.h.p. with what is essentially (2) Mamba 19T-TD04HL turbos though with bigger A/R turbine housings.

Now the bad part. Problem is the Juke stock turbine housing is technically rated to 5cm^2 which is very small. The odd thing is it actually measures .9" x 1.12" (2.286cm x 2.845cm) square or about 6.5 cm^2 at the volute entrance. I've had 5cm^2, 6cm^2 and 7cm^2 measured from my various Mitsubishi turbos and they measure out to their ratings in terms of cross sectional area but not the Juke. The Juke turbine measures and visually looks like mid-way between what a 6cm^2 and 7cm^2.

Anyway, now the actually measurements of the volute section of the Juke is making it more like a 6.5 cm^2 housing which isn't too too terrible but the transition into the turbine wheel is much more sharply abrupt due to the machining required to fit the much bigger TD04HL vs. the stock TF035HL8 turbine. This is really where the compromise of modifying a stock turbo comes into play. The pictures I'm showing here are a stock un-modified turbine housing for reference but it looks much worse in the machined version for the bigger TD04HL wheel. This might explain the backpressure that is limiting these turbos and part of the drawbacks of a re-worked stock turbo upgrade.

Port work on the turbine housing is an option but the turbine wall housing is thin as hell. When guys say they port their turbos, it's not going to be this area they would typically touch. Few if anyone would port a turbine housing to increase the A/R ratio. I've mentioned already there was some room for porting improvement in the stock exhaust manifold runner & collector and every little bit helps where you can get it. Looking at the inside of the turbine housing actually it's only thick enough to port the turbine volute on the inside portion towards the wastegate/downpipe exit side. This area can be increased to open up the volute from about .900" wide to possibly .960-.980" wide which would push the volute area to about a 7cm^2 for a good bit into the volute section. It's only possible to port maybe 1" below the turbine volute entrance near/below the wastegate but that actually might be enough. To make this work more effectively the 2nd pic shows how the volute "web" can be "slightly" cut back to allow venting early thru to the turbine wheel to take advantage of the opened up volute section to reduce engine backpressure. This area is called the B-tip height of the turbine wheel. This is probably a trade-off as that web is almost directly in-line with the waste-gate opening so it might affect boost creep or wastegate control but worth a shot. I've never tried it on another turbo but I'm willing to now. I'm looking at trimming that web back about 0.250" to .350" to let it breathe better. Anyway these Mamba TD04HL turbine housings are like $218 so fairly cheap.

So, I might drop the turbine housing next weekend to do a quick 30 minute port job touch-up in that area to get every last bit of flow out of the turbine.

 

[squirtbrnr]

I really hope this all works out for you. I'm reading through your posts and thinking "He knows his stuff, clearly, but what are the chances he missed one little thing or got one small calculation just out of spec?" What I'm hoping does not happen is you start the engine up and it's just fine and happy, but after the break in period you go to tune or do some pulls and the engine just says "NOPE!". If that does happen though, I really hope you do a teardown failure analysis even if you have no plans of ever returning to the Juke.

 

[pboglio]

I really hope this all works out for you. I'm reading through your posts and thinking "He knows his stuff, clearly, but what are the chances he missed one little thing or got one small calculation just out of spec?" What I'm hoping does not happen is you start the engine up and it's just fine and happy, but after the break in period you go to tune or do some pulls and the engine just says "NOPE!". If that does happen though, I really hope you do a teardown failure analysis even if you have no plans of ever returning to the Juke.

Appreciated. Your concerns are totally valid. I've seen professional engine builders have customer engine failures because they royally messed up. The engine specs kind of are what they are, not perfect as I had some issues with the 1st machine shop but the Juke is mostly within the upper spec limit that I can tell. There are so many tolerances I couldn't get into it but I have a full build spread-sheet documented for the entire build that compares my clearances/specs against the factory Nissan tolerances. I'm mostly comfortable with it but always can be improvement.

Would I do a teardown on a blown engine right after the break-in? Honestly the short answer is no. For many reasons I'd probably just part-out and move on from the Juke if that happened. Fun car but life has other adventures and time for me to move on at some point.

 

[Macgyver]

Yeah I think I would find the lowest mile block I could get and mount on the best stuff I could and hope it all works. Of course Macgyvering things here and there to make it better.

 

[pboglio]

OK, I have now confirmed I'm on the right track.

FP Performance designed my HTA68 turbo for the WRX/STi and that is shown below. The pictures show the HTA68 7cm^2 housing compared to the stock 5cm^2 Juke. They have done the exact same thing I'm recommending to do on the Juke. They cut back the factory Mitsubishi turbine in the volute web area with a die grinder, though the casting already is designed to provide this notch higher up in the turbine volute. The picture shows the round notch they created using a grinder to cut it back 0.10-.20". This now sits kind of high up near the turbine inlet which'll let it breathe better. The 2nd pic shows how much deeper this web sits on the Juke turbine vs. the Subaru turbine when compared side-to-side. The 3rd pic shows how similar in ID these (2) turbos are but it's a little bit misleading as the smaller Juke turbine starts necking down quickly the deeper it gets because of the smaller turbine wheel. That pic also shows how streamlined the turbine flow in the 7cm turbine volute inlet where there isn't the big wastegate port "step" that creates turbulence like the stock Juke turbine has. All that can be ported back and blended to make cleaner flow as well while simultaneously opening up the volute hole wider. Thus, the Juke turbine housing needs some decent port work to correct some serious flow deficiencies but improvements are possible without screwing up anything that would affect the turbine wheel.

So I now have some simple port work to do that should help the 19T turbo.

 

[pboglio]

Modeled below is the Mamba TD04HL machined Juke 5cm^2 turbine housing.

I ran the CFD computer simulation on that volute web clearance cut (i.e. +0.350") and yep the simulation is showing about a +10% turbine choke flow increase at the same drive pressure consistently. The simulation is running about 12 lb/min and and with the volute cut/clearance modification at the same drive pressure it goes up to about 13.2 lb/min. This is without the turbine wheel to avoid confusing things. This range of turbine flow rates seems kind of low but actually correlates very closely with the smaller Garrett 76 trim 0.57 or 0.64 A/R turbine flows rates on their turbine maps. But it's just a reference for % improvement. The remaining mass flowrate get's diverted to the waste-gate bypass. The extra porting makes a small/moderate difference but it's not as big and quite a bit of extra work so I'll see how it goes when I get in there to modify it.

Anyway, what this turbine modification translates into additional horsepower is that 290 w.h.p. might be pushed to 320 w.h.p. Whether that is the case is what I'll be shortly testing out on the road in the next few months. I also found out on this analysis that running higher turbine temps also kind of chokes the turbine earlier. So guys having backpressure issues might want to remove their turbo blankets to gain more top-end power at the expense of some spool-up. A lean A/F will do the same thing so there are some tuning variables to factor as well.