Given the mileage of our engines, logic tells me that the rings are worn and the turbo is causing more blowbys into the crankcase, is my thought.
Wits End Turbo Owners (7 Viewers)
- Thread starter spyduh
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Engine was completely rebuilt 20k miles ago so I’m pretty much just trying to discern if this is normal in FI engines and just needs to be mitigated, …or if I f’d up something in my rebuild 😂
Rebuild included the whole lot - block machined with new rings, pistons, etc. Cometic MLS HG, arp studs, and all the other common goodies.
Engine runs wonderfully otherwise - no codes, afr lambda is always between .9-1.1 (and not seeing any lean conditions under throttle), smoke tested the intake and exhaust sides with no leaks.
Around the 1k miles mark after installing the turbo I had the extra charcoal canister check valve Joey supplies go bad which caused a boost leak into the CC. I swapped it out for a new one and replaced the CC (again) for good measure, no issues since.
Rebuild included the whole lot - block machined with new rings, pistons, etc. Cometic MLS HG, arp studs, and all the other common goodies.
Engine runs wonderfully otherwise - no codes, afr lambda is always between .9-1.1 (and not seeing any lean conditions under throttle), smoke tested the intake and exhaust sides with no leaks.
Around the 1k miles mark after installing the turbo I had the extra charcoal canister check valve Joey supplies go bad which caused a boost leak into the CC. I swapped it out for a new one and replaced the CC (again) for good measure, no issues since.
My check valve went tits up too so that's not unexpected.
Your engine is tight so I find the oil in your turbo intake to be interesting.
Your engine is tight so I find the oil in your turbo intake to be interesting.
I think it’s expected there will be some amount of blow by on all engines, hence the necessity of PCV systems. I think FI (or higher compression pistons) exaggerates that blow by and also creates more of a challenge for the standard PCV setup since anytime you are under boost, you lose the “more direct route back into the combustion chamber” (crankcase to intake manifold).
The “some amount” is determined by tolerances and wear. Since your engine is fresh, you don’t have much…but still some.
Now, looking at what was in your intake, it looks like clean oil, rather than a fuel/water/oil mix like mine. There’s a picture I posted a few pages back of what I capture in my catch can.
One other to call out..prior to installing the turbo, how many people actually monitored how much blow by was passed from CC into intake manifold?
when I cleaned out my TB and intake manifold, there were years of dried blow by.
Soooo, what’s that all mean…
I would install a dual catch can system to capture as much blow by as possible and give you peace of mind. I don’t know if that amount of blow by would cause harm to the turbo compressor.
If you do install catch can, you can establish a baseline of how much blow by and what it looks like to keep an eye out. I started by checking it every 500 miles, then pushed out to 1K, and now just every 6 months or so.
I don’t even worry about blow by issues anymore, so it was $400 well spent IMO (I went with radium setup that was expensive but there are cheaper options)
The “some amount” is determined by tolerances and wear. Since your engine is fresh, you don’t have much…but still some.
Now, looking at what was in your intake, it looks like clean oil, rather than a fuel/water/oil mix like mine. There’s a picture I posted a few pages back of what I capture in my catch can.
One other to call out..prior to installing the turbo, how many people actually monitored how much blow by was passed from CC into intake manifold?
when I cleaned out my TB and intake manifold, there were years of dried blow by.
Soooo, what’s that all mean…
I would install a dual catch can system to capture as much blow by as possible and give you peace of mind. I don’t know if that amount of blow by would cause harm to the turbo compressor.
If you do install catch can, you can establish a baseline of how much blow by and what it looks like to keep an eye out. I started by checking it every 500 miles, then pushed out to 1K, and now just every 6 months or so.
I don’t even worry about blow by issues anymore, so it was $400 well spent IMO (I went with radium setup that was expensive but there are cheaper options)
in my experience, you will have some amount of blow by and oil in the pipes. i wouldn't worry about it. plus as already stated, what was your blow by BEFORE you added the turbo? were you worried then?
the fuel injectors will keep the valves clean by the washing effect. if you choose to run both a vacuum and boost side catch can, that's going to keep things even cleaner but to what gain?
on the turbo charged direct injection engines I own, I instead resort to intake cleaning very 40k miles as the injectors are below the valves so they get quite gunked up. re-plumbing the PCV system with dual catch cans is extra cost and complexity i've chosen to skip on a daily driver.
the fuel injectors will keep the valves clean by the washing effect. if you choose to run both a vacuum and boost side catch can, that's going to keep things even cleaner but to what gain?
on the turbo charged direct injection engines I own, I instead resort to intake cleaning very 40k miles as the injectors are below the valves so they get quite gunked up. re-plumbing the PCV system with dual catch cans is extra cost and complexity i've chosen to skip on a daily driver.
on the topic of years of blow by into the intake, don't forget the crap that the EGR dumps into the intake as well! Thankfully I did the EGR bypass right after the HG project, over a decade ago.
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Thank you all for the feedback! This all more-or-less aligned with my gut feeling that it wasn't the symptom of another obvious issue.
I definitely had some blow by in the intake before the turbo, just not on this scale. I've had a Radium dual catch can sitting on the shelf for six months, time to prioritize mounting it somewhere.
I definitely had some blow by in the intake before the turbo, just not on this scale. I've had a Radium dual catch can sitting on the shelf for six months, time to prioritize mounting it somewhere.
Thank you all for the feedback! This all more-or-less aligned with my gut feeling that it wasn't the symptom of another obvious issue.
I definitely had some blow by in the intake before the turbo, just not on this scale. I've had a Radium dual catch can sitting on the shelf for six months, time to prioritize mounting it somewhere.
In case you missed the earlier discussion in the thread about catch cans (several pages)
Wits End Turbo Owners
Hell yeah @CJK - I drove up to Truckee yesterday, 75 mph all the way up Hwy 80!
forum.ih8mud.com
Here’s how I mounted mine (separate cans):
Wits End Turbo Owners
That makes sense. I think I'll monitor and see how adding a valve right at the manifold helps. I also went down this path because I was noticing oil seeping out of the breather/intake hose connection, so I was definitely pulling oil that direction. Also, for the purists, I did have to mess with...
forum.ih8mud.com
While those locations and routing have worked, I’m sure there’s a cleaner way to do it. It definitely looks DIY
In case you missed the earlier discussion in the thread about catch cans (several pages)
Wits End Turbo Owners
Hell yeah @CJK - I drove up to Truckee yesterday, 75 mph all the way up Hwy 80!
Here’s how I mounted mine (separate cans):
Wits End Turbo Owners
That makes sense. I think I'll monitor and see how adding a valve right at the manifold helps. I also went down this path because I was noticing oil seeping out of the breather/intake hose connection, so I was definitely pulling oil that direction. Also, for the purists, I did have to mess with...
While those locations and routing have worked, I’m sure there’s a cleaner way to do it. It definitely looks DIY
haha yeah I’ve definitely read through this thread and the original turbo thread multiple times over the years. Your post was what originally pushed me to purchase the Radium can that been sitting on my shelf collecting dust for the last year 🤙
Im leaning towards mounting my dual can in the same position most people mount the York compressor since I have a dual ARB to put in the quarter panel. Should keep the hoses short and sweet…
That was my order.
90 degree fittings on top (inflow), straight fittings outflow.
8AN and 1/2” for the catch can between breather and intake air tube
6AN and 3/8” for the catch can between PCV and intake manifold.
Highlighted yellow is my $14.45 mistake of ordering 2 of same fitting. In red is the Qty needed.
The PCV Valve fitting is expensive ($40) but blocks boost pressure from intake manifold at the earliest convenient location.
This PCV valve seems much more robust than than the “grommet and plug” style in our crankcase.
Last note: I opted for 2 separate cans because I wanted flexibility to mount side-by-side or separate. You can also buy a dual can setup (which sounds like @haulin auss did), and mount cans together.
Installed the Landtank Scaled Injector kit (higher flow WRX injectors with an oversized ID MAF) last weekend on my Wit's End turbo charged J80. Drove it all week to let the computer learn with the new injectors and MAF. Did not notice any difference in starting, acceleration, or general driving. I have the 8.5 psi springs in the wastegate and saw that under WOT acceleration the wideband AF sensor was showing .82. Still rich. I am now going to install the Supra fuel pump and see if there is any change to Lambda AF numbers with that change. If that still looks good, the 10 PSI springs are going in and I will play around with that. I am not really after the max boost, but adding boost at lower RPM by the delay in the wastegate opening. The change when I put in the 8.5 psi springs was pretty big. When the boost comes on it ramps quicker and pulls harder. Under hard acceleration it does overshoot and hit 9 PSI, before the wastegate can catch up. The gas mileage is worst also. But, I put in an 18 gallon sub tank to offset the bad fuel mileage....
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This is not advised and not supported by anyone involved with this kit. The lack of timing adjustment with increasing boost pressures puts the risk of detonation very high and the rods at risk.
Ha!I knew you were going to be the first to reply......
Yes, I know, all at my risk. Joey did not intend for this kit to push the stock fuel system. He has been very clear from the outset that if you take it to higher boost and start modifying things, that is all on the user.
I do not have any detonation currently. Playing with it to see if I can get to the 10 PSI springs. I have been driving it for a year with the 8.5 psi springs, recording data early on. Up to the Sierra a half dozen times. A trip to Oregon up I-5. Towed an overland trailer that I borrowed. Performed great. I freshened up every sensor and fuel component except for the pump when I did the head gasket before the turbo kit. Added my own Methanol kit also, to reduce the intake air temps a bit under heavy boost.
Not my daily driver, my fun truck. The only problem I have had is I blew a hole in the cap on the PCV vent elbow on the top of the throttle body. The rubber one I had on there dried out and blew. Had to use a duct tape fix in the middle of nowhere. I now have a high temp silicon cap on there.
I do not drive with a heavy foot, usually. It does pull nicely up I-80 to the top of the Sierra. Set the cruise control at 65, A/C on, no temp problems and it just pulls along as everyone passes me. Too top heavy to go much faster than that.
Yeah the risk isn't the AFR it should be good, it is that usually you try and pull a degree of timing out for each pound of boost since IAT are higher, cylinder pressures are higher, etc. With the stock computer you don't have any control of timing, but if you have water/meth setup a decent way to keep the air charge cool and you have good AFR you are safer, but yeah never risk free.
What coolant temps are you guys seeing during normal operation and when say pushing it, also when it's cold out vs summer? Just curious.
Almost always 178-181 on my scangauge.
In the winter I have no issues with temps. They say in the 178-192 around town and maybe gets to 200 when going up to tahoe. In the summer pulling long steep grades where the blow off valve is working hard it gets hot. I’ve had to turn on the heater and roll my windows down to keep it cool. I’m going to get a Ron Davis radiator. My engine was rebuilt before the turbo was installed. New OME radiator, water pump and thermostat. Also installed the blue fan clutch. Thinking of hood louvers to get all that hot exhaust out of my engine bay.
