Oil pressure when dealing with high revs

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sniper

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A Honda tuning company named Whitfield Racing here in CA has a high NA power B20 VTEC engine. The car was only making avg. power until they found a way to relieve oil pressure some how and the monster motor put out something like 50-75 more HP. Anyone ever heard of this type of issue when dealing with high rev NA engines? Can you get too much oil pressure? What other oil related issues should one think about when looking to go beyond 8K rpm?
 
Sniper Id say yes you can have to much oil pressure, this will suck horsepower but not 50-70 hp more like 10-20 at a GUESS. Worse still blow out oil seals. You say beyond 8000 rpm, this is very high, I was talking to my bro yesterday about the same thing but in 3vzfe toyota engines as the MR2 boys all want high power 3vzfe motors. There's not much point in going for more rpm unless you can efficiently get the fuel/air in and the exhaust gasses out up that high rpm. If its a VERY over square engine you may get usable results if the above ie ( fuel/air in an gasses out) can be achieved but why run at the higher rpm? In a road engine you want long life and driveability, what are your aims? All out power at the expense of engine life driveability etc. Or was this just a general question.

Id say above all dont believe the hype matey, if it sounds to good to be true it most likely is. (untrue)
 

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Biggest oli problem I can see at 8,000+rpm is a conrod knocking the oil filter off the side of the engie as it flies out the side.

I don't believe you 8,000+ rpm to make big N/A horsepower.
 
Biggest oli problem I can see at 8,000+rpm is a conrod knocking the oil filter off the side of the engie as it flies out the side.

I don't believe you 8,000+ rpm to make big N/A horsepower.


*sn1gger*

The B Series honda engines looooove to rev hard. The S2000 motor has a stock factory redline of 9,000!!!! and even with the vtec make their power high in the rev range.

but 50hp gain? If that was the case then why didnt honda do it?
 
If that's true why hasn't any good dry-sump pump system got this?

I think that it is possible for an oilpump to put out such an enourmous volume, that the by-pass relieve valve can't relieve enough volume to get presure down and stays stuck open 100%, which in turn would send the pump in some sort of hydrolock because the engine won't take up the oil also, robbing power untill the pump gear eventually breaks. gen1 4age's had this sometimes, blamed to high rpm but more and more people are suspecting the relieve system to be the real blame. I had some serious problems with the relieve system on my gen1

I do believe you need to go high rpm to make huge power, unless you've got loads of capacity to play with,
LSpowers 850bhp unit does that at 8100rpm I'm told, so even when you have the iches you need high rpm to make HP, that's just maths and can't be denied. zuffen can you explain this matter?

Grtz Thomas

@ justin Exactly what I thought!
 
I thought we were talking normaly aspirated, what is this LSpower 850bhp motor? Im guessing FI yes? Not realy relivant im my humble opinion, I do know that 100bhp/litre is posible even in a NA engine but were talking lots of money spent on R+D to get close. FI is the easy way to get the power hike out of ANY motor 25-50% increase is posible without taking out a loan. Excess RPM will KILL any motor so why not just optimise everything you can on a NA setup or better still optimise AND go FI, trying to run at 1000 rpm above the factory redline or more doesnt seem the best way to go from a cost and engineering point of view. Yes it can be done maybe, but man it would cost mega bucks to do it with any degree of reliability.
 
I didn't say it was cheap now did I :Eyecrazy:
just wanted to point out High rpm is what makes high power, not torque
and yes it's an NA engine breathing trhough a set of 8 stacks. and 100 per liter is even less than what my bone stock 20v 4age spits out, it only does that at 7800rpm, compare that to an older 16v which does less rpm and gets only 140hp from the same cc's. there's no real advantage in head flow at peak rpms, so the high redline can be pointed at for the increased hp, on a torque base it's a whole different engine.

I've seen people go through enourmous trouble getting the PCV system to work properly on the 16v's with wet-sumps and very high rpm (9500+) in autocross scene over here. the early heads with the smaller return gallerys tend to fill the head up with oil, which can be looked at 2 ways: either the returns are to small (but can't be easily altered) or the reliefe valve is opperating above it's max flow thus oil presure goes up beyond reason, which is exactly what they measured on the gallery. I still can't see why this would be the case with a stock engine though, only when modified to run extreme RPMs for extended periods of time.
the Honda thingy seems like marketing tricks to me unless you're well aware of what you're doing and using fireblade like revs

Grtz Thomas
 
crank scraper about 2-6 hp, dry sump 5-10 hp, thinner oil about 5hp if your lucky, its also a question of right sizing the oil pump to suit the clearances you want to run.
I call bs on freeing up 50 hp in an NA car.
On another forum the sub-title of the ALL-motor section is:
"For the deep pocket people"
NA build up needs deep pockets or a lot of creativity.

Mike
 
50-75hp is crazy.

excessive oil pressure will indeed rob HP, but its about controlling your oil flow so you can lessen the oil pressure and gain power.

this in my eyes is on the skilled end of blueprinting an engine.

IPS, the leaders in K20a power actually are going to a smaller bearing to pickup a few HP. they grind down the crank mains to a smaller diameter, then run a bearing with a smaller sectional width.

the new trend is...smaller surface area...less frictional loss.
 

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50-75hp is crazy.
...

the new trend is...smaller surface area...less frictional loss.

That has always been true, but the compromise is to keep the bearing temps under control, you also need to consider crank stiffness, as in flex of the crankpin.

Mike
 
I suppose the B20 built was not quite a fair example. That was a full race motor with a compression ration close to that of a diesel. I am talking about the 1UZ that will live in my S13 which is pritty much just a weekend race car. Turbo power is nice but iv been there, done that. Plus it adds weight (ya ya i know you can make up for the weight with the power blah blah blah, thats not the point!) and it adds lots of heat, yes lots. High reving NA is just my style and im doing it because thats how i would do it, its just that simple. My car is for long canyon runs or track days. Yes the heads have to be gone through to figure out how i can get the motor to breath at high revs but im also planing on getting a set of cams made to help with this. The motor should also have pistons to get it into at least the 11:1 range.
 
completly redesinged in/ex ports are also in mind, when revving over 8krpm.

I was thinking, maybe we can go the same route as the hayabusa turbo guys, a dragteam from over here have welded up the complete intake port and "stolen" a cosworth port profile which the cnc'd in the head with an enourmous gain in power.

that would be sort of a cheapish way to get a profile that's proven and well engineered, and when you're at it coppy the cam profiles aswell,
GM did that in the past with stolen desings of ,GM bought, porsche 911's aswell and apparently with good results.

welding up shouldn't be that hard, only time consuming. and can even be done using some sorts of epoxy resin though I doubt that that would live long.
5axis cnc milling isn't as expensive as it used to be anymore by far, so this might prove a nice way to try some stuff, last time I checked my head shop charged more than the local hightec machine center cost so....

I think/hope maybe Erol RMS can shed some light on this.

grtz Thomas
 
THe last 1,000rpm you plan to use will most likely double the cost of a N'A engine.

The last 1,000rpm will probably gain you 5-7.5% at the expense of lower down drivability.

May be worth chasing the power for the racetrack but not for the road.
 
completly redesinged in/ex ports are also in mind, when revving over 8krpm.

I was thinking, maybe we can go the same route as the hayabusa turbo guys, a dragteam from over here have welded up the complete intake port and "stolen" a cosworth port profile which the cnc'd in the head with an enourmous gain in power.

that would be sort of a cheapish way to get a profile that's proven and well engineered, and when you're at it coppy the cam profiles aswell,
GM did that in the past with stolen desings of ,GM bought, porsche 911's aswell and apparently with good results.

welding up shouldn't be that hard, only time consuming. and can even be done using some sorts of epoxy resin though I doubt that that would live long.
5axis cnc milling isn't as expensive as it used to be anymore by far, so this might prove a nice way to try some stuff, last time I checked my head shop charged more than the local hightec machine center cost so....

I think/hope maybe Erol RMS can shed some light on this.

grtz Thomas

Wish it was so simple Thomas.
Our next 1UZ has raised inlet ports, about the limit you can do on a 1UZ. We are using Cosworth BDD cam profiles. The 3UZ head appears to be a better base but I haven't got my hands on a pair yet.

The 'cosworth' port profile is designed with the correct ratios re valve angle/port angle, valve included angle, valve dia/bore dia etc.
On some motorcycle air cooled engines you can probably get close to cosworth. They generally have better bore/valve dimensions to start with.
The Cosworth engines have not had more max power than other engines but a wider and more useable spread.

With CNC machining beware of the hourly rate, it is normally machine time only and does not include initial 3D solid models or tool path programing.
Our dry sump/engine mount pan took around 40 hrs to solid model and 8 hrs tool path programing, then actual machine time.
 
Thomas,
The roof of the port is raised 5mm at the manifold face, and tapered to original at the guide boss. The floor is left original, the slight chamfer at manifold face is filled.
Injectors have to be moved back, and to clear head and runners they have to be thin pencil (piezo crystal) Siemens injectors.

We have 36mm inlet valves and 32mm exhaust.

We are also looking at filling the recess between ports and removing the port offset, as well as offsetting the inlet guides to allow 37mm valves.
 


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