r33_racer

Oil drains can be opened up to 10mm max. The governing body there is the holes in the head gasket are 10mm. I think they are 8mm standard (holes in the block/head). There is a small 5mm one I think at the front of the block also which I am not sure how big it can be opened up as I have never touched it. The best oil drain option to help is the bunged off hole between cylinder 3 and 4 on the exhaust side. It is the lowest point of the head and already on the exhaust side so it can be plumbed straight into the sump as an extra drain. However, once again when the crankcase pressure is too high, any extra drains you add or enlarge purely just become vents. The opening of the drains is also a commonly known mod in the oil control thread. If its not listed in there its listed somewhere in one of the many oil control threads through out this forum that have been started over the years.

I think you may have a too higher regard for how well things actually work inside a combustion engine. You will never get a perfect seal constantly in a round metal bore with metal rings running up and down it at constantly varying rates of speed. We strive to get the bores as round and true as possible via torque plates and what not and the rings hopefully as close to suiting the bore as possible also, but its never a perfect fit. Its hard to picture it in your mind, but the rings are not totally sealing up the bore on the compression stroke or power stroke. There is gasses leaking past the rings in several ways; through the small ring end gap if the gaps aren't ideal, between the bore and piston ring and sometimes behind and then under the ring. Its not a perfect situation at all unfortunately. The more power we try to make the worse it all gets. The blow by might only be 1-2% of the total volume of air/fuel in there, but that can be quite large when you look at how much air needs to be there to support (x) amount of horsepower over (x) rpm. There is some good information out there about blow by and how it all works and how to calculate roughly how much your engine has. I may even invest in a blow by meter so I can start getting some solid information about this stuff. Would be handy to have.

I think what people are forgetting is that every engine has blow by. It's just typically not enough to be an issue. Everyone is aware that its impossible to 100% seal up an engine. There is always a small amount of leakage and in a boosted application there is going to be more leakage then in a NA engine, purely because the cylinder pressures are that much greater as the engine usually makes considerably more power. A thicker ring that has more sealing surface area will also have more radial tension which will seal up much better then a thinner ring unless the design is improved someway to help. Though strictly comparing the same style, just different axial width the thicker ring will always do a much better job. What I don't get is how piston manufacturers can supply rings that much smaller then standard to work in engines putting out in some cases more then 3 or 4 times(in some cases alot more) the factory power output. Like I was saying before the old school rule of thumb for a performance/race engine was 1/16" 1/16" 3/16" rings which worked great in both NA and boosted apps. Thin rings may help make another 2-5hp over thicker ones due to less drag but they wont last as long or seal as well. They have gone thinner so they can brag that their pistons will help make more hp then competitors. At the end of the day they are a business and are in it for money. For me its a matter of I know it will work for him if its done right. Its worked for me on several engines now. I guess people wont believe it until they try it themselves or see it in person. Its hard to argue that your piston/ring setup is better suited then the piston manufacturers own setup. Anyway, sorry for hijacking the thread.

The reality is the thin rings do work. Just no where near as good as they should. If the thin rings worked well then alot of the bandaid oil control mods and fixes would not be needed. The majority of the bandaid fixes in the oil control thread dont really work 100%. Especially in racing conditions. The only bandaid fixes that I have seen work personally on my own cars and other peoples cars is either mines baffles in the cam covers to physically stop the oil from coming out and the crankcase vents which I mentioned before. The only real fix I have seen work is the use of thicker rings to improve ring seal to the point where blow by is almost totally eliminated, enough so the oiling issues don't even happen. Once people start understanding that the root of the problem is to do with excessive crankcase pressure rather then purely too much oil in the head the sooner they will understand what fixes actually work and what don't. Right from the start the initial diagnosis has been based around too much oil in the head, though it is part of the problem it is in no way the main culprit. It is what everyone has gotten used to being the problem and because of this they dont look at anything else that could be causing it. I can tell you alot of people who do all the main oil control mods still have the same problem afterwards. Every case is different though, as every engine is built differently with different parts so no one engine can be gauged on the merits of the commonly done mods. Just like you cant compare a stock internal 15 year old engine to a freshly rebuilt engine that is getting tracked. My whole point is that there is more to this problem then just the over oiling. Everyone has been so focused on one area that nothing else even gets looked at as possible contributor. Djr81 happens to be looking at another area which he thinks is contributing to the root problem.

I do not agree with GTScotT. I have done back to back tests on both our race car and my road car in regards to rings and breathing over the last 2-3 years. The oiling issue is directly related to blow-by. RB's do not breath well at all and they don't drain oil back very well, this is very common knowledge among experienced RB engine builders. The main fix for stopping the oil from blowing out your cam cover breathers and filing your catch can is to put crankcase vents on the inlet side of the sump (the breathing side, this is also a common fix amongst the experienced folk) to vent the excessive crankcase pressure (blow-by) directly out of the engine and into a catch can/breather can. This tells me that whilst using any standard after market piston/ring package(as this is when the problem is most noticeable, not so much with std piston/rings, though not undocumented) there is excessive blow by being generated, though it may not be a lot, it is enough to stop oil returning to the sump whilst being held under constant high rpm load like experienced in racing situations. The blow by builds up in the crankcase and tries to vent through both the internal vents and oil drains and in doing so holds the oil up in the head and starts carrying it out the cam covers and typically fills a lot of the catch can to the point where it violently pushes the oil out of the filters and make a nice big mess in your engine bay. Let me say also that having a higher volume oil pump also contributes as it is only putting more oil everywhere in the engine, however it would only be 25% of the overall issue, the rest is contributed to excessive crank case pressure. I've looked at all the pistons we have used over the last 7 years of racing and noticed that all of them have very thin rings. Typically in the 1.0 to 1.2mm range. The common old school methodology for a reliable performance ring set was 1/16" top 1/16" 2nd and a 3/16" oil control ring. The closest metric equivalent to that is 1.5mm top 1.5mm second and a 4mm oil control ring. The increased sealing surface area drastically reduces blow by, right to the point where the oiling issue completely goes away. Even more so you will notice that the breather can filters will have almost no fumes at all. The thicker rings can handle more heat before losing tension, they also can transfer more heat into the bore. In a forced induction engine, the rings need to be able to handle the extra heat, and cylinder pressures in order to keep the bore sealed as perfectly as possible. The reality is the thinner rings just don't cut it as well as they should in a turbocharged engine. They cannot handle alot of heat and they certainly cannot handle the pressure. This is evident by the fact that by putting vents on the sump cures the pressure build up in the crank case and lets the breathing/oiling system work in a normal fashion. I'm not really fussed if people don't believe me. This is what I have found to work and it works very well. I reckon djr81 is heading in the right direction.

Finally! Good to see some updates! Ridiculously neat job with everything you have done mate. Love it!

We were racing there last weekend. You were talking about the accident on Saturday when it was raining? It took a long time to get him out! No doubt they are in it for both reasons. Sell safety to everyone they can for a price! I was only told the story via second hand info and that bloke probably didn't know the full story either. Good old Chinese whispers. I guess the point is you are ultimately going to stand a better chance using one then not. Despite how annoying they are, they are a good idea.

At Lakeside now they are heavily pushing everyone to get a HANS device. A bloke died not long ago there from a broken neck. The lesson learnt from that was had he been using one he more then likely would have walked away from that crash. They are heavily pressing the issue now. I don't like crashing or coming off the track, but I'm sure one day it could happen and when that day comes I would like my head/neck to remain in its current position and configuration.

Its hard to quantify any gains from port work without doing back to back tests. You really need to do a stock head with all the same bolt ons. Then try a worked head with all the same bits and compare results. However, not many people actually have the time or money to try that exactly. Everyone gets tempted by changes when they have the engine apart lol.

Very nicely done. Time to go shred some rubber!

The HKS springs look almost standard....but with some fancy blue paint on them. The new springs look good! What lbs are they at seat and open?

Isn't that the truth! Were you logging AFR's when your injectors were failing? Because we have noticed issues with the Bosch injectors in our race car also. It seems over time the alcohol swells the rubber seat inside the injector and they gradually lean themselves out. Its possible your injectors may have been flowing closely when you got them, but this issue presented and left them partially stuffed and now they flow out of spec.

-10 in and -10 out is normal size for oil system plumbing. If the oil pressure is low then something else is causing it. You should be right to leave it. You could run a slightly heavier grade of oil which should help bump up the pressure.

Correct. Not sure if it would be adequate, but its certainly better then nothing. No solid stream of oil should go up it as its sitting at the base of the sump rails which is well above oil level.

It's on the wrong side of the engine to act as a vent. It is directly opposite where the vct oil bleed off runs out on the inlet side of the head. My guess is it was placed there to help let the extra oil that is bleeding off down to the sump so as not to overwhelm the internal drains. Remember the inlet side of the block is the venting side and the exhaust side is the draining side. If your exhaust side drains are working as vents also then that means you have excessive blow by. Hence the crank case is pressurised and its using every internal and external drain/vent to try and escape to atmosphere. During this process bugger all oil is allowed to drain and some of it will get carried out the cam covers and into your breather/catch can with enough force to blow out your breather filter/s and make a nice mess everywhere. To cure this you need to add an extra/s vents on the inlet side of the sump direct to catch can to give that extra crank case pressure/blow by an easy route out of the block direct to atmosphere. If its adequate enough, then the engines internal venting/draining ports will work as per normal and you should no longer get violent pressurised air/oil blowing out your catch can. The better fix I have worked out involves running thicker rings on both the top and second ring(1.5mm) that can better handle the heat generated and seal up the extra cylinder pressures that come with the extra horsepower we are all making/chasing.

Yeh the extra overlap creates that problem. More air goes out the exhaust valve then on a std cam setup, usually the more overlap the lower your compression results.

Love your car mate! Looks the shit. You should have got the workshop to do a leak down test, that would more accurately tell you how bad your blow by is and what condition the engine is in. Compression tests don't really tell you the whole story. The other trick you could have done to help the oil control issue is take your dipstick out and put a hose on the tube and run it to your catch can. It will help vent the excessive blow by that was causing the oil to blow out of your cam covers. Good work on coming up with a better baffle system for the cam covers too mate!

The ACL/Ross pistons I have seen have the closest ring set. I have ACL/Ross's in my RB25 and they have a 1.2mm top and a 1.5mm second. Maybe they have changed it to a 1.5mm on both which is great news!

What are you doing for sump options? Going to add an extension or something? I highly advise putting a crankcase vent on the inlet side of the sump above oil level and plumb that line to your breather can. -12AN should be sufficient, otherwise you can run 2 x -10AN lines. It should be easy to do if you already have your sump off. Dont want to see you have oil control issues and spray oil all over your freshly cleaned engine bay! It's the worst feeling when you have oil dripping out of every crevice!

I would have thought above oil level would have been better then below. However, that drain wont really do much. You need to vent the inlet side of the sump. So just get one welded on there and you will be sweet.

What about the old trick of two flywheel bolts and a big flat blade screwdriver or pry bar in between and get someone to hold while you breaker bar the bitch out, 3ft waterpipes for each end maybe required.

Get a fitting welded on the inlet side of the sump, as high above oil level as practically possible. Make it -12AN and run that line directly to your catch can. If you want to use the rear head drain, then run it to the exhaust side of the sump, as it might actually have a better chance of working like a drain in that configuration, though you wont need it anymore if you do the -12AN crankcase vent on the inlet side.

Nice work! Love it! Series 2 wing FTW! The series 1 wing is homeless...

I never said it wasn't good enough. I don't care for the use of proper English or not. But the way the engine parts were listed could have made it slightly confusing for others. So back on topic, I have had acl bearings with almost no blueing on them and some with lots. I think it's apart of the coating on them.

I think the lack of punctuation is creating that confusion. I'm gonna guess its a second hand r34 crank, but new std oil pump. The blue staining is std on acl bearings. They all tend to have it, just some have more then others.