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Oil pump modifications.

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FyxxterZC

20+ Year Contributor
148
1
Sep 30, 2002
Morganton,
Does anyone have any suggestion for any slight modifications to increase/smooth out oil flow on a new front casing? Or do I need the stock oil gallies in the front housing to stay the cast size to maintain pressure? I have a new topline front oil pump/casing and I am looking at any and all modifications I can do to help engine longevity and oil pressure/flow.
 
1. Smooth out the casting flash in the 2 front oil passages in the block (radius the main galley entry while you're at it).
2. Pull the squirters and block them.
3. Install balance shaft removal kit.
4. When installing pump gasket, cut the part that extends thru the oil passages. I believe I Hylomar'd the gasket to the pump, then used an Xacto knife to trim away any gasket that would reside in the passages).

I ended up with about "ONE MILLION" psi!!! OMG

Actually, when it's warmed up, I'm probably around 20+ psi at idle. The cylinder head see's about 1/2 the block psi at idle. At anything above 2500rpm it's probably around 90 ~ 100 psi. And I shift around 8k rpm at the track without problems. No leaks, no blown filters. Using the Toga high volume pump, pumping thru an external cooler and large filter with ~8ft -8AN hose. So YMMV.

If your next question is "what thread size is the oil squirter?" I don't remember... ended up finding heat treated bolts and cutting their length to fit, using a lockwasher and liberal application of JB Weld on the threads before running them in.

Hope this helps.
 
You can also modify the oil bypass valve relief hole in the oil filter housing to allow more oil to bypass under pressure. This will keep you away from the 100+ psi cold start up pressure days.
 
Tevenor said:
You can also modify the oil bypass valve relief hole in the oil filter housing to allow more oil to bypass under pressure. This will keep you away from the 100+ psi cold start up pressure days.
I've always wondered how I could fix that.
 
Mirage2LTurbo said:
Are you suggesting to block off the oil squirters that squirt on the pistons/cylinders?

Although a nice to have, they aren't necessary. They do help cool the piston and help longevity but plenty of people rip them out to increase pressure and flow to the spots that need them more.
 
It's pretty "obvious" where the piston squirters are.

N/A engine blocks do not have squirters.

You'll have to "Search" for pictures of the front cover (oil pump) and what hole needs to be ground out... I've seen it posted somewhere... it'll make sense if you hold it in your hand and look for the hole where the regulator spring resides... then you should be able to figure out at least the direction you should be grinding the hole ;) , if you cannot, then you probably shouldn't be OMG .... oh never mind...
 
:laugh: yea i have a few n/a blocks here and i knwo they dont have squirters. i was more interested in the rest of the whoel deal. im gonna take a look at the blocks and the front casei have im my garage and take a peak . thanx
 
Cool. Glad you understand :thumb: , sometimes people get a little thick around here.

You'll be amazed at the amount of casting flash the factory leaves in the blocks. A whole lottttaaaa improvement to made with an air grinder in just a few minutes. Prep/cleaning will take longer than the actual grinding.
 
yea im gonan check it out. i assume your talkin abotu thew galleys in the block that are behind the front case in the block. i can see some rough stuff inthere. i will get a gasket kit befor ei send my block out and grind it down. i ge tit a bit now

i have my front case but im gonn aorder another welded for balance shaft removal. im gona be runnin 10:0:1 compression, a 100 shot and 8500 rpm shift point hopefully. the motrs gonna stay n/a. i kinda made it my goal to hit 250hp n/a without nitrous and add nitrous on top.

if i do this setup oil psi is a must at those rpm's
 
Okay, I just happened to look at the oil pressure gauge at my AN line going into the engine:

197F coolant temp, 750 rpm idle, Mobile-1 10W30, pressure is 14 psi.

Front case just needs the balance shaft removal kit. That and maybe doing the pressure relief mod. No welding involved.
 
tmizer said:
1. Smooth out the casting flash in the 2 front oil passages in the block (radius the main galley entry while you're at it).
2. Pull the squirters and block them.
3. Install balance shaft removal kit.
4. When installing pump gasket, cut the part that extends thru the oil passages. I believe I Hylomar'd the gasket to the pump, then used an Xacto knife to trim away any gasket that would reside in the passages).

I ended up with about "ONE MILLION" psi!!! OMG

Actually, when it's warmed up, I'm probably around 20+ psi at idle. The cylinder head see's about 1/2 the block psi at idle. At anything above 2500rpm it's probably around 90 ~ 100 psi. And I shift around 8k rpm at the track without problems. No leaks, no blown filters. Using the Toga high volume pump, pumping thru an external cooler and large filter with ~8ft -8AN hose. So YMMV.

If your next question is "what thread size is the oil squirter?" I don't remember... ended up finding heat treated bolts and cutting their length to fit, using a lockwasher and liberal application of JB Weld on the threads before running them in.

Hope this helps.



when you radiused the hole how much did you radius it. i smoothed mine out a little but people are tellin me it wont help pressure. i did all of the above and will trim the gasket when i get to that point but i didnt radius it to much because i didnt wanna take to much out. how much of a radius did you put on it. heres a pic of what i did. lemme knwo how much more then this you went


http://www.dsmtuners.com/forums/showthread.php?t=154226
 
When you clean the oil galleries you are not going to gain oil pressure you are going to make sure the oil pressure you have got (controlled by the bypass spring) gets to were it is suppose to go without restriction, by cleaning galleries the oil pressure will stay more constant throughout the whole engine. Who said you will have less pressure by the time it reaches the head? pressure will be there but the flow wont!! due to the restrictions all the way to the turbo.
 
burldude said:
I have a suspicion that it is just equipped with a stiffer bypass spring and maybe smoothed casting.

Actually, it isn't. I recently found out that the gears are of a different design and it actually does increase your oil pressure.

I shot Cragger @ SBR an email about this a while back and they verified its the real deal and I believe they are now selling them. Anyone doing a build up should look into this type of front case. Next time around I'll definitly be going that route.
 
Typical DSM'er response,

:thumbdown
"Who said you will have less pressure by the time it reaches the head?"
:thumbdown

Answer: 2 gauges, one at the block and one at the head. You do realize there's a oil pressure regulator bolted into the head at the end of the galley fed from the block? And I've on occasion done the Bart Simpson rev the engine by hand and looked at both installed gauges, revving and saying "oil pressure goes up... oil pressure goes down...oil pressure at the block is X psi, at the head is 0.5X psi" Ignorance really is bliss....

Na90dsm: As far as type of radius, a high r/R (r=entry radius, R=bulk turning radius) is desired, and what it'll net in final pressure, it may actually net LESS pressure on the intererior gauge or a guage on this passage. Why? Look at the equations for head loss or minor head loss in a fluids book... regardless, from the images you posted elsewheres, you shouldn't have a flow rate problem at all, and I wouldn't be so concerned with pressure now, as the bearing gaps and head galley are what will now most closely determine oil pressure at this point, and not front oil passage friction or turning lossses from the sorry factory block finishishing.

...now make sure everything is VERY clean before you start reassembling....
 
I have been running and advocating the use of two gauges for over 3 years now! As far as I am concerned, head IS the most important place to measure your oil pressure, because that is the last place that sees oil. If you oil pressure in the head, you have it everywhere else. You can’t say that about your stock location…

Another problem with stock location, it that it is before the filter and before the oil pressure relief valve. Oil pressure measurement at that point is almost meaningless…

Next, who said that we need MORE oil? Why are people looking at “high volume” pumps? The only explanation that I can think of is: “That is what they do for V8”…

Whenever we have a “build motor”, without balance shaft and squirters, we usually have TOO MUCH oil pressure! If anything, we need to do things that will REDUCE (not increase) our oil pressure at high rpms. That is where enlarging oil pressure relief valve comes into play. It is the same principle as porting your wastegate opening. When properly done, it will not have any effect at idle oil pressure but you will be much less likely to “overrun” your oil relief valve above 7000 rpms.
 
GRNDSM said:
Next, who said that we need MORE oil? Why are people looking at “high volume” pumps? The only explanation that I can think of is: “That is what they do for V8”…

Whenever we have a “build motor”, without balance shaft and squirters, we usually have TOO MUCH oil pressure! If anything, we need to do things that will REDUCE (not increase) our oil pressure at high rpms. That is where enlarging oil pressure relief valve comes into play. It is the same principle as porting your wastegate opening. When properly done, it will not have any effect at idle oil pressure but you will be much less likely to “overrun” your oil relief valve above 7000 rpms.

I see your point and I meant to say HIGH VOLUME and not HIGH PRESSURE in my previous post. Regardless, my point is that people should take it into consideration when doing a build up.

For example I think that would have been a great mod for my car because I'm not huge believer of blocking off the oil squirters on a street car even though I run forged pistons. Also, I've only elminated my front BS and the rear I had machinced and balanced if you will because I opted for the stubby shaft. So in my application I don't entirely agree with what your saying. Again, I think people should 'consider' it when doing a build up.
 
thats bloody intresting. i've never thought of smoothing out the front 2 oil passages for better flow. im going to do that this week!! im building a 6bolt 4g63 to put into my 96 eclipse. the engiens going into the shop to get hot tanked, im deffently going to hit the grinder before it goes in!! great idea, great thread!
 
>I see your point and I meant to say HIGH VOLUME and not HIGH PRESSURE in my previous post.

In this case, higher volume leads to high pressure because oil relief valve can not keep up with all that volume.


>thats bloody intresting. i've never thought of smoothing out the front 2 oil passages for
>better flow. im going to do that this week!!

I give up...

Or better yet, if for some strange reason you want higher pressure, you could always shim the spring in the oil relief valve to make it more difficult to open. :rolleyes:
 
i only said it may effect it a hair, not like 5 psi or anything. maybe effect it by a psi. im not looking for tremendous amounts of oil because its pointless on a n/t block. has no squirters which will boost it, and block off bearings from the balance shaft removal will net me more then enough oil to do whatever i want.

i just did it to make sure everythign flows smoothly mainly, just to make sure the oil isnt disrupted by anything and flows nice and freely well as much as it can.

i think i started somethign bad here. i only did it for those 2 purposes, not to gain any pressure. itll give maybe , maybe 1psi.
 
The oil pressure relief slot mod is a must. GRNDSM, can you post a link to that mod?

Now 4G63 head head oiling requirements are relatively low, hence the regulator at the head. When a 4G63 head was used at Purdue to operate a pulse detonation engine rig, the machinist, and a future coworker of mine ran into the oil pressure problem of all things. When I later asked them what they eventually ran for pressure, they seemed to recall 40 psi being a bad thing....so definitely enlarge that slot.

...which leaves main and rod bearings, which, ULTIMATELY determine oil pressure as their annular clearances with the crank being essentially orifices, critically controling oil pressure in the main galley. If the 0.0018~0.002 DSM clearances were increased slightly to say 0.003, that would drop a 100 psig main oil galley to 70-ish psi...if one were to build a "loose" engine for example :D

My reason for front oil galley porting, no squirters/bshafts, and better pump was two-fold:

1. Reliability.
2. Increased flow capacity for an external oil cooler/filter system which adds head loss.

Na90dsm, I thought we talked about enlarging this slot before? If you can do that galley, the slot is cake.
 
Anyone have a pic of the Oil Press Bypass enlarged? I to just want to know the location. I haven't really looked at my oil pump. It on my garage floor atm so I'm going to look it over but I definitly am going to be doing some extensive polishing of the oil galleys and passages as much as possible before I put my motor together. I'll probably end up going through like 8 can's of cleaner after I'm done to ensure my block is totally clean.
 
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