Negative crankcase pressure - Dyno tested - Gold 4age 

Noting really to do directly with content in this video. But its another good example of how easily dyno results can be wrong/ manipulated. The baseline run in this video was done with engine and oil temps the same as all other runs. 95c oil. 80 water temp. but produced less power than the identical setup at end of video. why? I didn't run the car very long before the initial run. so things like gearbox and diff oil would have been still fairly cold. The end "new baseline" directly overlays from the last time i ran the car up a week ago. So dyno is accurate in those regards

0.1psi crankcase pressure at 7000rpm+ . not bad for a 300k block with a dingleberry hone, complete with vertical scores. 200k+ ? 2nd hand rings and pistons, all from different engines !

My favorite series i click you videos right away, love the tests i constantly think of your videos when working on my civic to try and get the best NA numbers haha. Keepem comin!!

Your like the "master splinter" of 4age 👌

I installed a van type vacuum pump on a 1972 Alfa Romeo 2.0 engine in the place of the stock Spica mechanical fuel injection pump. I converted the car to EFI. It ripped out the front crank seal initially. I then placed a vacuum gage on a spare oil cap and installed a filtered air bleed in the crank case. I regulated the vacuum to -12 psi. The added power was dramatic with seat of the pants dyno. I regularly add full cylinder head Back exhausts , ported heads, high compression pistons and camshafts to these engines. The stock Spica Injection is ITB. The power of this completely stock tired engine with only the vacuum pump, ITB efi, and full exhaust was similar. How much was the vacuum pump and how much the EFI I cannot say. But I am running the same air fuel and timing at full throttle with the Spica and the EFI.

loving the content, keep it up

Very cool video, I like the real and raw data! ❤️🏆

Next video: Homemade Dry sump - Dyno tested - Gold 4age XD

Nice test, waiting for more. Thanks Man.

Not sure who came up with this idea, but I'm glad you did a second baseline run.

Best Videos on YT :) (Y) i love your Dyno "Mod" Comparison Vids Thumbs up

I've read engineering studies of this before.. (I like your vids btw, and raced a AE86 for 25 years).... Negative pressure does produce more power. run the valve cover vent through a check valve to the header and if you have it in the right spot will pull a nice vacuum. I was tempted to do, but never did.

Used a crankcase evacuation system on my Ducati BOTT bike. Simply a check valve from a Chevy plumbed into divergent cone of exhaust. I had cut a 45 degree angle on pipe entering the cone, but the angle was open to the engine to use the return wave from the convergent cone. I wanted the weaker pulse rather than the stronger positive pulse as I didn't want to draw oil out of crankcase even though I had a large vapor/oil separator. The engine would go into negative pressure at 2,000 rpm. But the power increase that a crank evac system will bring has more to do with proper piston and ring selection. Because the pressure differential across the rings is greater with negative pressure, builder can use lighter tension rings which reduce the frictional drag. Also, you can use only one compression ring and one low tension oil control ring because with more pressure differential, rings work better. Also keeping ring side clearance at absolute minimum will stop ring floating because of inertia. Once this happens, ring collapses and no longer seals. Crank vacuum helps hold ring onto land at TDC to help prevent this.

Those headers are sick

Excellent...data is data and the dyno don't lie. Good to see a proper test done on this, many thanks. That's a healthy blow by rate for that age of engine.

Great video mate. Might just install that vent to atmospheric catch can after all. On my race car that is

Damn nice header !

Seriously ancient vacuum 👏👏

I had terrible oil burning issue on my 4.6l 2v turbo motor due to the turbo drains running almost horizontal. I ran a check valve to my crank case from my intake manifold. It would suck the oil from the turbo drains and stopped my burning issue. Not the proper fix but it did work.

Im in love with your starlet, I sold mine years ago for bugger all to a young fulla who went on to crash it. Your videos have got me wanting another one but I have far to many old rusty toyotas as it is lol

Thanks bro, excellence content..

Interesting video. I’ve often wondered about fitting a vacuum pipe to the oil catch can and to see what results if any that achieved.

Keep 'em comin!

Very interesting. I think the benefits show up more on low tension, drag like ring packs, however I do no know offhand how much the belt driven vacuum pumps they use make in terms of vacuum and Im sure the size of the engine will skew it one way or another. I am quite surprised its absolutely nill on yours.

Brilliant thanks

Would love to see this on the turbo 4age as well and see what crankcase pressure it has before and after.

You probably won't see many gains until you pull more vacuum, of the big drag motors with dry sumps I have played with we usually shoot for 16 inches of mercury in vacuum, which I think is around 8 psi, this is generally considered the safe limit before you start turning seals inside out, but I found that you really, really have to try to seal a big block to get that much vacuum. there are definitely gains to be made, but it really is 10/10ths stuff. Keep up the great videos mate.

I have a 4e-fe with DIY turbo kit. After seeing this I will be using a sump return on my catch can. I don't want to empty my engine of the 3.5 l of oil. Moreover, the drain will also directly ventilate the sump while not relying on the valve cover vents.

You need at least -12 psi. Try installing a pan-o-vac system in the exhaust collector with an oil air separator. You should be able to achieve a much higher vacuum. It will make power. You will need a very effective oil/air separator with a drain back tube. To effectively create power you must remove the resistance of the air from the back side of the pistons. The rapid back and forth air movement is a high source of friction, combined with oil flying everywhere. The air is pulling and pushing on the pistons with great force at high rpm. Removing this air in combination with better ring sealing will add significant power. It would be interesting to see how much on a small displacement engine.

That header! Damn

BOOST!!! Would love too see this test on boost!!!!

i used a 98 cobra smog pump to pull a constant 2-3" of vacuum into a catch can and the car definitely liked it, I wonder if getting it up to 10-15" if I'd see real power gains

God damn i'd love to have my own dyno at home! Could play around with the twincharger all night trying different shite. Good video. How about a crankcase vacuum on a boosted 4ag?

Henry Hoover had no idea what he would be snorting this day

Instal a tube at a 45 degree angle in your collector. Run a hose up to your oil air separator. Between the separator and exhaust instal a one way air pump check valve. This will generate a real vacuum. For a true power gain. I would love to see actual gain and at what vacuum.

Was discussing this with my mates just last week...

Could you test that with turbo setup? Keep up the good job

Haha, thanks for this!

Those headers! :D

Your content soooo good make me subsribed to your channel instantly… hope you can make a video and dyno test about oil cooler vs no oil cooler in future. Thanks

idk if the comparison is try to draw limes to that of a dry sump vacuum, but i think the dry sump power gain is the fact the oils scavenged out and evacuated from the block so the rotating assembly is not hitting oil but then im left asking whats the power loss from the parasitic drag of a dry pump setup to not only have a negative crankcase pressure but evaluate gains of not having the oil hitting the rotating assembly

I have done several engines with proper dry sump and with the oil pump/vacuum pump connected to the crank, it increases the efficiency with rpm. I saw several engines making 15-22hp more than conventional oil sump. One thing that is very important is the closed head cover, you need to block every intake of air in the engine, and let the vacuum system pull the entire air only. It will seals the piston rings a lot better and making more power. Also you need to pull vacuum from the bottom not the head. Applying vacuum with out removing the stock oil pump it’s useless as you well tested. 👍

Super!

Thought about knife edging a crank and polishing the rods while you're there for a before and after, I think knife edging probably won't be as effective these days because we use thinner oils than the olds school stuff.

neg crankcase pressure really only benefits high displacement high rpm engines, and needs to be around 12-15Hg. Any lower no point, any higher get oiling issues. Neg pressure promotes better ring seal to produce more power

Your test proves incredible thorough character for truth on an incredibly well designed engine! question: is there a 1gge that could be the 6 cylinder version of the 4age?

I Like your Videos! I have an Idea. A video with different fuel types and octane Numbers. Like in Germany wenn have Aral ultimate 102 octane and Low one with 95.

I’m curious as to what it would be if you were to have +1psi added to the crankcase

Hi Buddy, Interesting experiment. I made some testing with negative crankcase pressure on a naturally aspirated 4 cyl water cooled VW, and found out a problem. My objective was to test a closed circuit, meaning that blown-by gasses would be totally recycled and the crankcase would remain at negative pressure at all times. Not so simple as it looks like. It never is. You have to remember that all pressure reduction in the crankcase will reflect directly in the lubrication system pressure, since the oil pump will be sucking oil from a negative pressure level. Be cautious about this when experimenting with negative crankcase pressure. Let´s say you have negative 7 psi in the crankcase at idle, your oil pressure gauge will read also 7 psi LESS. If the engine is not designed or properly prepared to run like this, better let it breath to the atmosphere, even if you have some positive pressure build up with hi revs or load.

I want to make an exhaust siphon to lower or go negative on my Lycoming aircraft engine. Mainly to reduce oil leaks on what should be called a Leakcoming engine.

Try one with 'heavy' oil such as the engine restore stuff and one light as possible oil ?

Iirc, my 79 celica with the old 18r had a vacuum pump as standard,

You might gain more on your turbo motor because if the extra blow by

I wonder what the result would have been on a bigger engine or with turbo and more blow by with looser ring gaps.

I think you need to have a lot more vacuum. I think it’s to have less air in the crankcase so that the oil fall down faster away from the rotating assembly

Nice starship

good music

The main point with running vacum in the crankcase is the use of way weaker oil control rings, right?

My first impression was "Wow, not much blow-by".

Hi, your videos are awsome! appreciate your effort doing the dyno test to show the truth of many myths!, i wonder if you could helpe cheking my vvt map on my 2zz ge toyota?

My plan is to run my pcv system first though a catch can, and then to a Venturi style extractor in the exhaust to draw vacuum on it.

Was there AFR differences with the vacuum applied ?

Can you test the improvements from increasing the compression ratio on this na motor?

I wonder what a big ring gap big cube LS would be like

👍👍

Are you measuring the crankcase pressure with just a regular MAP sensor?

Low engine blowby. Good job. Next episode - mopping the muffler from inside :)

Did u do anti reversion devices

Hmm. What happens if you pressurize the breather to offset the drop in PCV vacuum at higher throttle angles? Breather being upstream of throttle (atmospheric pressure) and PCV being connected to vacuum of intake manifold. I’d be interested in seeing what happens if you offset the drop in vacuum at WOT with a corresponding increase in breather pressure

Huh interesting. I would have thought the negative crank case preasure would increase the high torque at least a tiny bit. But I guess this engine doesn't have much blow by

What was the negative -Hg u test at?

Try 15" of vacuum

From what I've seen, the difference is made with reduced oil in the sump due to reduced windage. Nick's garage proved 5-7 hp on engine dyno on lower revving V8. So: dry sump. Corresponds with the amount of oil you sucked out, ckrank spins in dense oil mist.

I think most dry sump setups run about -4psi (8 inches of Mercury). Tee in an extra vac or two 😂

I understand vac pump on the c-case is to keep oil out of the combustion chambers. Oil can detonate easily causing damage. If you boost it, this will save parts $$$. Nice video

no any noticable diferences, gain with vacuum in only when piston goes down, what about oil seals that could be destroyed and dirt could get in engine through them

Do a test adding pressure instead please!

I love you.

Wow, effectively no gains with -2PSI? I feel like vacuum pumps are run in some big money drag racing. Those guys are often fighting for a couple tenths of a second, hard to believe they would be running the parasitic loss of a vacuum pump (that's not plugged into the wall), while not seeing in gains and just not notice. Maybe this is a function of large ring gaps for power adders vs a tight NA motor?

Yeah this is something that would have been worthwhile if you were running a turbo and say, 3 bar of boost? Would have shown it’s benefits on a setup making triple the power, but neat experiment nonetheless

Shows your rings are in great condition! could you do this on a boosted motor, please!!?? @garage 4age

As piston travels down it needs to suck, when piston travels up it needs to blow 🤣🤣

Great work! Did you happen to notice any oil pressure change when running the high vacuum test? Two schools of thought, the oil pump has to work harder on the inlet side (decreased oil psi), or less 'head' pressure on the output of the oil pump (increase in psi). future tests, -vary oil pressure. The standard is 1psi/1k rpm. Maybe .5psi/1k to ++psi/1k? -different oils, OW-20 to 20W-50 -oil temps -water temps -fuel temps, running iced fuel compared to heated Thank you!

This is interesting that on the 4age there's no benefit, because I do know some engines do benefit from running vacuum pumps to reduce crankcase pressure, even in NA setups, dyno verified. I wonder if the 4age just doesn't have the same sort of internal design that causes some engines to benefit from negative crankcase pressure.

I know this is an old video. I had to chime in on this one .. Vacuum pumps are used mainly this day in drag cars and or where you are running super low tension piston rings (you guys get the point). your test does not indicate your piston ring setup.

I'm sorry but I just wont believe this. Negative crankcase pressure will reduce the density of air in the crankcase, and thus reduce the aerodynamic drag in the crankcase. Maybe the 4AGE just has a good design for the rotating assembly in the terms of aerodynamics, or maybe the reduced VE from higher compression leaks reduce the torque as much as is gained from the lowered pressure, idk.

What setup are you running ??

Good test in theory, however i have done this many times using a drysumped engine and a vac reg. There isn't normally a power gain until crankcase reaches 15hg. Then there will be more drag on the oil pump, so gain is less than if you could use a seperate vac device.

Shit where's all my oil gone!? Vacuum 👀

I say do it again but closer to a perfect vacuum.

missed an opportunity to block all breathers and test the negative impact of positive crankcase pressure, probably more noticable on your boosted engine. You were kinda solving a problem that wasn't there given that even the factory pcv had crank case pressure at 0.1 psi

gapless rings please

This should be more like -10 PSI and preferably measured and/or reported in inHg

🤭... lo que aguanta ese motor toyota no tiene nombre... jajajja

Wait, 450 NM toque?

Attach it to exhaust now

I wanna see -10 to -20 psi

I think on a forced induction motor the effect of an evacuated sump would be more pronounced.

Yo, is this thing 170 whp?

maybe it only matters at like 15k rpm