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Your oil consumption is fine just check it after every session and keep it topped up.
The engine carnage starts when you start having serious fun, specifically as soon as you stop running stock tires and put your first set of big sticky tires on. That's usually coincidental with more acquired skill behind the wheel.
I burnt up 4 sets of Sets of Michelin Pilot Sports in my first year of high performance driving in my street 928. towards the end of that season I was getting pretty fast and was pushing the street car pretty much to the limit. The last time I came off track that year I could hear the lifters clattering away like an old set of tappets. Upon consultation with Greg Brown about all the clattering noise coming from the heads I pulled the oil filter and it was full of babbit which turned out to from the 2-6 bearings. I was that close to loosing a motor.
Bottom line your street car engine will be fine as long as you keep the oil level up and run stock tires with street tread wear numbers 200 or higher. Get used to sliding the car it's fun! The minute you put big sticky tires on your street 928 you will be at risk of blowing your engine, as soon as you can hold a 1.0 g or more in a turn for a prolonged period ,say 2-3 seconds, you've entered the danger zone, I would suggest installing a visible oil pressure gauge in your car if you continue to track it, if you see the pressure drop you know you've reached the limit. Old fashion analog not digital, the digital's don't react fast enough
You can trust me on this I've blown up more 928 engine than possibly any one. 6 and counting , but who's counting! lol Good Luck! or you could just let me drive your car and see what happens!
Unless you feel like playing Russian Roulette and dying 6 times (see post #31 above), here's the "Gospel, from Greg" on "928 High Performance Use....DE Events".
1. Stopoil from getting into the intake system....whatever it takes. If valve cover breathers and filler neck baffles will do this job, for you, that's great! If you need to add an oil separator in addition to those items, do so.
2. Do not run "blindly" install chips that increase the rev limit or add ignition timing (all performance chips do this) to the engine, without running race fuel....especially on engines without knock sensors. On engines equipped with knock sensors, monitor the amount of knocks per 10,000 cycles. Anything over 75 knocks will damage the rod bearings.
3. Change the oil pick-up in the oil pan to an "early model" style pick-up with the clover leaf piece in the bottom of the oil pan, the pick-up with the rubber boot, and the screen. Install a pan spacer and a pick-up spacer. Run the oil level at the stock levels on the dipstick, when at the track.
4. Monitor the debris in the oil filter. Buy an oil filter cutter and spare oil filters (alternatively, you can buy a System 1 Oil Filter.) Cut open a few oil filters that have a couple of thousand street miles on them, to get an idea of how much "silver" debris is "normal" for your engine. Cut open an oil filter every single day at the track. If you see a significant increase in the amount of "silver" in the filter...or you see any "gold" in the filter, stop having fun....because the fun is about to not be fun.
Semi-retired, as of Feb 1, 2023.
The days of free technical advice are over.
Free consultations will no longer be available.
Will still be in the shop, isolated and exclusively working on project cars, developmental work and products, engines and transmissions.
Have fun with your 928's people!
I gotta say this became a pretty interesting thread, I appreciate the advice and feedback by every body.
I took the side air boxes off the intake tonight.
Passenger side had maybe one tbsp (5ml) pictures below. And drivers side was actually dry.
I would have to credit Greg’s baffle for that.
On a side note, the passenger front tire has a funky wear pattern in it, I tried to take a profile pic. Kind of a ridge that tapers down on each tread around the outer edge.
This was the tire that I could feel set on the banked curve. It that typical or do you think it’s from hitting a candy cane or unrelated?
They are (were ) Continental extreme contact all season.
I wonder if that stock "oil separator" 928.107.731.01 (plastic cup/tube) on the underside of the passenger cam cover could suck lots of oil into the intake when the head fills with oil. If it's pulling a vacuum and the oil level is above the opening it seems it should act like a drinking straw.
I gotta say this became a pretty interesting thread, I appreciate the advice and feedback by every body.
I took the side air boxes off the intake tonight.
Passenger side had maybe one tbsp (5ml) pictures below. And drivers side was actually dry.
I would have to credit Greg’s baffle for that.
On a side note, the passenger front tire has a funky wear pattern in it, I tried to take a profile pic. Kind of a ridge that tapers down on each tread around the outer edge.
This was the tire that I could feel set on the banked curve. It that typical or do you think it’s from hitting a candy cane or unrelated?
They are (were ) Continental extreme contact all season.
Tread creep.
Full height tread will stretch and warp as you turn, always. Go to the track and now you're asking way more, and its ripping and starting to chunk the tread blocks apart.
DOT race tires are often shaved down quite a bit to prevent this.
You would think more rubber = more laps, but once you start chunking and tearing it apart, you lose the tire quickly.
Nothing wrong here, just a street tire at a race track.
And more wear inside to outside, is a function of the tire rolling under the wheel and a lack of total camber..which is a function of camber+caster settings, etc..etc..etc..
You can see how much tire you did NOT have on the ground in hard turns..about half wasnt contributing or so because of "things"..but all these "things" are a compromise, you dont have a track car, you have a street car.
A pre-ignition event originates during the previous fuel combustion cycle, when fuel injected into the cylinder interacts with oil on the cylinder liner forming an oil-fuel droplet. At the end of each combustion cycle, the oil-fuel droplet is usually expelled from the cylinder; however, from time to time, the oil-fuel droplet remains and may trigger pre-ignition in the following cycle, the team showed. "Car makers need to break this chain of events to suppress pre-ignition," Singh says.
(Perhaps this explains partly the problematic S4-up cylinders #2 and especially #6, whose intake legs flow the best, possibly also ingesting the most oil?)
Originally Posted by GregBBRD
Increasing the amount of ignition timing (aftermarket chips) combined with the reduced octane increases the pounding of the bearings.
Note that much of the S300s ignition advance is less than stock (for expected use with an X-pipe). (The maps were tuned with the aid of a knock sensor on multiple engines.) An expanded air temp retard map with a load-based third axis tries to keep performance as high as possible, safely. For track use, I have suggested removing the air temp sensor from the airbox, keeping it plugged-in but in the hotter engine compartment.
Worth noting, for the skeptics, is that Jorj's 219mph open road race car is fitted with both my crankcase breather and my valve cover breathers, This engine, very obviously, lives at high rpms for extended periods of time, under high load conditions.
Before the installation of my pieces, this engine was pushing out/using large quantities of oil....enough that he was concerned about there being enough oil left in the sump to not cause bearing failure.
Worth noting, for the skeptics, is that Jorj's 219mph open road race car is fitted with both my crankcase breather and my valve cover breathers, This engine, very obviously, lives at high rpms for extended periods of time, under high load conditions.
Before the installation of my pieces, this engine was pushing out/using large quantities of oil....enough that he was concerned about there being enough oil left in the sump to not cause bearing failure.
The engine now uses no oil, during this event.
In all fairness, the coincident change in George's car was to go from pump gas to high octane race fuel. Before going to race fuel, by my memory the engine did not have oil ejection problems at 5800 rpm. When the peak rpm was increased to 6200 rpm, there was blowby and oil ejection. Given that it is a centrifugal belt driven blower, the manifold pressure goes up quite a bit between 5800 rpm and 6200 rpm. Without higher octane fuel, one gets knocks. With knocks, one gets excessive blowby. With excessive blowby, one gets oil ejection.
Jim Morton did the engine right for George's 219 mph car. It's at the same time a very stock engine and a very special engine.
In all fairness, the coincident change in George's car was to go from pump gas to high octane race fuel. Before going to race fuel, by my memory the engine did not have oil ejection problems at 5800 rpm. When the peak rpm was increased to 6200 rpm, there was blowby and oil ejection. Given that it is a centrifugal belt driven blower, the manifold pressure goes up quite a bit between 5800 rpm and 6200 rpm. Without higher octane fuel, one gets knocks. With knocks, one gets excessive blowby. With excessive blowby, one gets oil ejection.
Jim Morton did the engine right for George's 219 mph car. It's at the same time a very stock engine and a very special engine.
Perhaps worth noting:
Andy's naturally aspirated 6.5 liter engine was also fine, at 5800 rpms. At just over 6,000 rpms, oil blew out of every valve cover vent we had, which all went back to the air filter box. There were no knocks.
That event is what "sent me" on a multi year hunt for solutions.
Andy's naturally aspirated 6.5 liter engine was also fine, at 5800 rpms. At just over 6,000 rpms, oil blew out of every valve cover vent we had, which all went back to the air filter box. There were no knocks.
That event is what "sent me" on a multi year hunt for solutions.
The crankcase gas and oil flow problems are certainly harder to solve when the rpms get higher and stroke longer.
The crankcase gas and oil flow problems are certainly harder to solve when the rpms get higher and stroke longer.
One of the great things about working on so many different 928's is that I get to see/build not only hot rods but a large quantity of pure stockers. One doesn't have to pull off many plenums on the '85/'86 engines and get one's pants and feet completely covered with oil or tilt a freshly removed intake from an S4 and make a huge oil mess to realize than there is a systemic "issue" with most all of the 928 engines. Huge amount of oil get deposited in the intake system.....and as the cars got newer (GTS engines) and turned more rpms (GT engines), the problem got worse.
I certainly originally built my pieces for high performance engines....however, somewhere along the way, I decided to apply some of those pieces to stock (or relatively stock engines.) The results were amazing. I can build a 5.0 to 5.8 liter GTS or GT engine and have virtually zero oil reach the intake system, with the addition of a crankcase baffle and some valve cover breather pieces.
Absolutely a huge improvement with a very small cost.
In reality, I no longer build any engines, remove and re-install any valve covers, remove any water cross over, without these pieces. And it's not about profit....I'm never going to pay back the time I spent doing R&D on anything 928 related....the "market" is too small....and that's never been what I'm about. I've never woke up and even given a momentary thought about how much money I was going to make that day.....I simply don't care.
It's such a dramatic change and improvement that even if there's no "room" in the budget and I have to give people these items, they get installed!
And I'm betting if you were to ask George (Jorj), there would be a zero chance of him removing these pieces.....
One of the great things about working on so many different 928's is that I get to see/build not only hot rods but a large quantity of pure stockers. One doesn't have to pull off many plenums on the '85/'86 engines and get one's pants and feet completely covered with oil or tilt a freshly removed intake from an S4 and make a huge oil mess to realize than there is a systemic "issue" with most all of the 928 engines. Huge amount of oil get deposited in the intake system.....and as the cars got newer (GTS engines) and turned more rpms (GT engines), the problem got worse.
I certainly originally built my pieces for high performance engines....however, somewhere along the way, I decided to apply some of those pieces to stock (or relatively stock engines.) The results were amazing. I can build a 5.0 to 5.8 liter GTS or GT engine and have virtually zero oil reach the intake system, with the addition of a crankcase baffle and some valve cover breather pieces. Absolutely a huge improvement with a very small cost.
In reality, I no longer build any engines, remove and re-install any valve covers, remove any water cross over, without these pieces. And it's not about profit....I'm never going to pay back the time I spent doing R&D on anything 928 related....the "market" is too small....and that's never been what I'm about. I've never woke up and even given a momentary thought about how much money I was going to make that day.....I simply don't care. It's such a dramatic change and improvement that even if there's no "room" in the budget and I have to give people these items, they get installed!
I agree that much can be done with reasonably small modifications, if those modifications are well thought out.
My personal favorite "easy" improvement is to vent the engine to manifold vacuum from the back under deceleration and from the front under acceleration. During the deceleration, oil sloshes forward inside the engine, so one should vent crankcase gas out from the back. During acceleration, oil sloshes to the back, so one should vent from the front. I don't really understand why the factory did the opposite for S3/S4/GT.
04-10-2019, 03:04 AM
) Continental extreme contact all season. 
