Building a 10,000 rpm NA engine. - Page 2

oab_au · #16 06-09-2012, 07:16 PM

I don't agree with upping the pressure to get the flow. That will only break the pump rota. Its the flow that we have to get. Pressure doesn't hold the bearings off the crank pin. If the passages are large enough and free flowing then there will be ample oil at the shells.

This is not only a EG33 problem the Nissans have the same problem, same pump. We had a Nissan RB30 that did the rear bearings. Acting on the oil surge theory, the sump was trapped doored like Rally Bob's sump. Still ran the rear bearings. Increased the pump pressure, broke the pump rota.

I had a side valve V8 blown to 14psi. This engine had the worst oiling system there could be. The pathway the the big ends was painfully, so bearings ran. I rearranged the pump to external and ran the oil through copper pipes through the side of the block to feed into the bottom of all the main bearing caps.
The engine ran to 7k with that boost and never did a bearing again.

Head gaskets were a different problem.

I would like the see if there is a chance of getting at the rear of the gallerys, to supply at both ends. Even fitting an accumulator there, to cover the low times.

Harvey.

oab_au · #17 06-09-2012, 07:31 PM

Quote:

Originally Posted by svxfiles

OK,
If the stock crankshaft is good to, say, 9,400RPM,
and you want a reliable 8,500 RPM,
then we need lighter/stronger connecting rods and bolts,
lighter/stronger pistons and,
lighter/stronger piston pins
to lessen the rapidly rising kenetic forces.

I know that our stock piston/pin w/rings (1#, 6.4oz)
and rod (1#,58oz)
weigh 2#, 12.2 oz EACH!(or 1250-1260kg)
I remember that the CP pistons/pins and Eagle rods weighed alot less.
And we (if our pockets are deep enough

) can buy them.

Next we come to the valves/springs/keepers/retainers, as far as weight being an issue.
Are titanium valves/springs(?)/retainers/keepers available?
If we cut the weight of all of these things in half, then you should be able to raise the RPM limit by a pretty big margin.
(IMHO)
Tom

Yes the reciprocating weights are the limiting factor. The top end of the rod, piston weight, particularly the piston pin, have to be the place to start.
The same applies to the valve gear. Unless we go to Desmodromic.

.

Harvey.

Dessertrunner · #18 06-09-2012, 07:33 PM

Great input, love it.

OTom we may need to change the pistons and rods as you suggest but I want to fix the oiling problem and a few other things first, other wise I might waste money on a set of brand new piston and rod that get distroyed.
Are we agreed which are the best pistons and rods to buy and can you post me a link to them. If we all agree I am happy to buy them just won't install till we fix a few other issue. Never though about the weight factor but it would have to help with the crank doing what you said.

Mr Harvey sir (its sunday and I must be respectfull). All your points are correct but (sorry about the but) I don't intend on wasting my time with the current pump. We have moved on, what we need to do is understand what oil isn't getting to the back bearing if that makes sense so then we can do some thing about it.

Don't want to bring this up but what we did with the cooling was measure things then we had number to point us in the right direction. This project is all about measuring things.

By the way I have started a spread sheet with different bits of data so I will all OT weight number if thats okay.

Tony

SVXRide · #19 06-09-2012, 08:06 PM

Quote:

Originally Posted by Dessertrunner

Great input, love it.

OTom we may need to change the pistons and rods as you suggest but I want to fix the oiling problem and a few other things first, other wise I might waste money on a set of brand new piston and rod that get distroyed.
Are we agreed which are the best pistons and rods to buy and can you post me a link to them. If we all agree I am happy to buy them just won't install till we fix a few other issue. Never though about the weight factor but it would have to help with the crank doing what you said.

Mr Harvey sir (its sunday and I must be respectfull). All your points are correct but (sorry about the but) I don't intend on wasting my time with the current pump. We have moved on, what we need to do is understand what oil isn't getting to the back bearing if that makes sense so then we can do some thing about it.

Don't want to bring this up but what we did with the cooling was measure things then we had number to point us in the right direction. This project is all about measuring things.

By the way I have started a spread sheet with different bits of data so I will all OT weight number if thats okay.

Tony

Tony,

We are definitely on the same sheet of paper, sir! Instrument, measure, move forward. One change at a time vs multiple changes at a time. Verify and document!

Will your planned dry sump support Harvey's idea of routing around the stock oiling system to up the volume to the rear bearings?

Bill

svxfiles · #20 06-09-2012, 09:29 PM

Geeze,
Its 11:27 PM, and now I have to go down to the garage,
look at an engine,
and actually think.

Sigh.....

oab_au · #21 06-09-2012, 09:33 PM

If it makes you feel any better.

Its only 1.39 PM here, plenty of time for that.

Harvey.

svxfiles · #22 06-09-2012, 09:37 PM

OK, First a noob question;
Is there a bolt on Subaru oil pump that flows more volume than the stock SVX 3.3 oil pump?

oab_au · #23 06-09-2012, 09:41 PM

As you would know we have the 12mm wide pump, don't know of a wider one.
Have to be off some other engine.

Harvey.

svxfiles · #24 06-09-2012, 09:46 PM

I just looked in my "pictures" on my computer and found that Eagle rods weighed 540 grams,
our stock rods with much weaker studs weigh 620 grams.
ACTUALLY, after looking further into the old pictures the stock SVX rod weighed 628 grams, on THAT day on THAT scale!
So, 88 grams per rod, X six.
I'll look further to see if I can find piston weights.
Our rods are supposed to be fine at normal RPMs, but the stock studs are the weak link.
It ALMOST costs as much to upgrade to ARP studs as it does to get some better rods.
I have seen generac rods, with ARP studs for as cheap as aboput $300.00 USD
However, I would have to buy three sets of four, $1200.00 USD to get two sets, and at the time,
I did not have enough money to buy a second set.

smc · #25 06-09-2012, 11:39 PM

Running a dry sump system would solve a few issues with high rpm running. To aid in the flow to the back of the engine, it would simply be a matter of tapping into the oil passage and incorporating another pressured oil feed to that section of the engine. This is a common practice in a few different motorsports. This way you have equal pressure. A dry sump will also eliminate issues of cavitation from high rpms, and create a vacuum in the crank case allowing for a better environment for high rpm rotation as aerodynamics will no longer be a factor for the crank and pistions.

One of the major problems I can see is for cooling. You may want to go with an electric water pump thats independent of the crank. At the speeds your looking to obtain, stock style of pump will be experiencing cavitation like crazy and will be trying to push more air than water. Effectively stalling the flow of coolant.
That, and the coolant would be moving to quickly through the system to effectively remove heat from the engine block.

Best way to combat this is with a high volume automotive electric water pump. It will happily be pumping away at what ever rpm your engine is running at.

Feel free to correct me if im wrong here.

Dessertrunner · #26 06-10-2012, 12:31 AM

Bill yes I think we should figure out a way to increase oil flow at the back of the engine. Maybe what SMC suggests is possiable. It would be good to map out oil flow parths. One thing for sure I can't seem to follow the manual image.

SMC we called bearing step 2 because we think rightly or wrongly that the cooling issue (step 1) is solved we spent years sorting it out and I think Matt and Bazza has proved we have it beat. I am not a beliver of electric water pumps they just don't pump enough liquid. Sorry to disagree about that. As regards the rear tapping I think thats a great idea, its along the same lines as Harvey point, I am sure Harvey would agree we need to find a improvment on the copper oil line.

Good input guys. OT can you supply all the weights in metric as you find them please.

Tony

oab_au · #27 06-10-2012, 03:10 AM

Quote:

Originally Posted by Dessertrunner

Bill yes I think we should figure out a way to increase oil flow at the back of the engine. Maybe what SMC suggests is possiable. It would be good to map out oil flow parths. One thing for sure I can't seem to follow the manual image.

SMC we called bearing step 2 because we think rightly or wrongly that the cooling issue (step 1) is solved we spent years sorting it out and I think Matt and Bazza has proved we have it beat. I am not a beliver of electric water pumps they just don't pump enough liquid. Sorry to disagree about that. As regards the rear tapping I think thats a great idea, its along the same lines as Harvey point, I am sure Harvey would agree we need to find a improvment on the copper oil line.

Good input guys. OT can you supply all the weights in metric as you find them please.

Tony

That would be the way to go, but we need to see a sign that there is a problem in the flow, before we engineer a cure of nothing.

I suspect that it may be a problem, but it is not easy to check.
You can't just drill a few holes in the oil gallery, fit a gauge, to check.

An engine that is being built up could be drill, taped with large enough holes, to accommodate a oil feed, if needed. Gauges then could be used to check the pressure around the system.

Tony the oil from the pump runs up to the pressure switch, then splits to each side. The RHS runs from the switch to feed the rear journals 5,6,7, that feed the rear big ends.

Tom the rod's weight is more important at the little end, as that is the reciprocating weight, the bottom does not matter that much, as it just adds a bit of flywheel mass.

It would be interesting to compare the reciprocating ends of the standard and the Eagle.

Harvey.

Dessertrunner · #28 06-10-2012, 04:22 AM

I am confused I was under the understanding that when you look at a SVX engine the direction of rotation is clock wise yet when you look at the pump you get confused. The botton pocket is the suction and also the bypass return the small round hole is the supply to the filter then back to the bearings.

So at the back of the sump is a pipe coming from the back of the engine.

Were is that coming from, I lost???????

EDIT have sort the direction still need to figure were the back pipe comes from.

Dessertrunner · #29 06-10-2012, 04:37 AM

A couple more photos you can see the oil gallery on the left and right top of block as Harvey meentioned and you can see one of them turn up at the back of the engine.

oab_au · #30 06-10-2012, 06:27 PM

Quote:

Originally Posted by Dessertrunner

A couple more photos you can see the oil gallery on the left and right top of block as Harvey meentioned and you can see one of them turn up at the back of the engine.

If you mean this Pict. It looks like the plug to the right of the crank, near the separator plate, would be the end of the gallery on that side, and the feed to the rear main.

You can see that there are plugs at the front of the two gallerys, and one at the rear of LHS gallery. How about pulling them out and seeing what size of the gallerys are.

Harvey.