Porting the oil relief hole with no balance shafts?

[perley03]

Thats really weird. How old is your pump? Where do you have your sending unit tapped into? My pump was brand new in July, but the motor did not run until October. My sending unit is tapped into where the factory one was. I'm running a Faze oil pressure guage, electronic one. I'm thinking about putting in all Autometer guages when i get my income tax check. I got the oil filter housing off right now, just looking around as to see how much further i should port it to relieve some pressure. I was also thinking about turning one of the balance shaft bearings so that half the hole lines up with the oil galley, maybe that would help loose some pressure. But I really don't want to do this, and install the engine, and start it and have no pressure, and have to tear it all back apart again to fix it.

 

[01QuadDak]

Since the Turbo piston has a "step" on it, and the N/T doesnt, what about milling the step off of the turbo piston?

 

[GVR4592]

I can't believe yours is that high at idle. I mean my car with 20w-50 in 30 degree temperature will only get to about 25-30psi sitting at 800-1000rpm idle at first startup. Normal driving (slow acceleration and 3000-4000rpm shift, tranny hates cold weather) still won't see it get much above 80psi.

Are you using the N/T oil filter housing?

 

[mavisky]

No my entire front case setup is out of a 1990 awd including aftermarket external oil cooler.

 

[project_tsi]

No my entire front case setup is out of a 1990 awd including aftermarket external oil cooler.

Kyle I thought the 91+ oil pump gears were the gears of choice no? Because they are cut diagonally not straight cut like the 90 oil pump gears.

 

[mavisky]

They are, but my motor is by no means "The Ultimate 4g63".

nt crank and block with no squirters, 150,000 mile old stock 1g pistons, 90 oil pump

It's just what I had laying around when I popped the last motor, but she's a fighter and she's holding up pretty well all considered.

 

[project_tsi]

Gotcha. Interestingly enough, when I pulled my front cover on my 91 laser's 6 bolt, it had the straight cut gears. Either it was a 90 engine or the last owner put on this front cover. Its got a oem cover on it now with the diagonally cut gears.

 

[project_tsi]

I ported out my relief hole last night. I hope this is enough.

 

[90turbotsi]

Just a bit of FYI the diagonal cut pump gear/driven gear are the updated/redesigned gears used. Yes they are better and "less noisy" from what ive been told.

 

[project_tsi]

The straight cut oil pump gears are 1990 gears. 91 and up have the diagonal cut gears. And yes, any straight cut gear will be louder, think about dog box trannies.

 

[danl]

Just a bit of FYI the diagonal cut pump gear/driven gear are the updated/redesigned gears used. Yes they are better and "less noisy" from what ive been told.

They are not "better" in any way with respect to performance. It was a TSB because it was a little noisey when you first start the car. Me, I don't mind it I actually like it. It's a DSM noise IMO.

 

[kicker91laser]

Just a bit of FYI the diagonal cut pump gear/driven gear are the updated/redesigned gears used. Yes they are better and "less noisy" from what ive been told.

They may be redisigned and less noisey, but keep in mind the straight cut gears do not create a side load on themselves and the case like the diagonal cuts do.

 

[Turbogsxmitsu]

Hey fellas, what if I tried 5w-30 motor oil? Do you think that would be safe and would it lower my oil psi?

 

[DSM90AWD]

Hey fellas, what if I tried 5w-30 motor oil? Do you think that would be safe and would it lower my oil psi?

A 30W oil will produce less oil pressure than a > 30W oil at the same temp. As for safety, I will refer to the following oil FAQ:

Always use a multi grade with the narrowest span of viscosity that is appropriate for the temperatures you are going to encounter. In the winter base your decision on the lowest temperature you will encounter, in the summer, the highest temperature you expect. The polymers can shear and burn forming deposits that can cause ring sticking and other problems. 10W-40 and 5W-30 require a lot of polymers (synthetics excluded) to achieve that range. This has caused problems in diesel engines, but fewer polymers are better for all engines. The wide viscosity range oils, in general, are more prone to viscosity and thermal breakdown due to the high polymer content. It is the oil that lubricates, not the additives. Oils that can do their job with the fewest additives are the best

I've used 10W30 Mobil 1 exclusively for 17years / 135K miles on my car without any bearing/turbo/oil pump failures and zero sludge in the pan. Though if running significantly higher than factory RPMs / temps, a heavier weight oil may be needed to keep your oil pump/engine happy

 

[JWoodley]

Did the porting solve the problems for you guys or did the piston change workout?

 

[mavisky]

The porting alone solved all of my issues and I run Mobil 1 15w-50 in the car.

 

[Elvenhome21]

when I am not racing the car I run 5w20, oil pressure is right around 75 psi all the time

 

[d j]

Did the porting solve the problems for you guys or did the piston change workout?

I'm not so sure on this idea anymore - What I've done is use the internals (spring & piston) from the Non-Turbo... Works great for me.

The relief hole (diameter) is the same size on an n/a vs. turbo. What I couldn't test was the spring rate - but i swapped internal components and all is well. I've since then sold the car but my fix for the over pressure was to use the N/A oil filter housing internals.

 

[AL92]

I think may have spun a bearing in my 4500 mile engine. I ported the relief hole and dont have a real guage so not sure if maybe oil pressure is too. low. So you said should have around 25psi idle and 80 at 8000 rpm? Is there a minimum that would be dangerous also. say 10 and 50 at 8000 or something. I should get a real guage I guess.

 

[92GSXman]

I know this post is old but I was wondering if you guys had any updates? I am building a NT 4G63 block with turbo pistons and also eliminating the balance shafts. Not drilling the holes for the turbo oil squirters either so I know I'll have high oil pressure if nothing is done. I'd like to port the housing (90 style turbo housing for oil cooler is what I'm using) but I'd also like to try the NT piston in the oil filter housing if that will work.

I looked in CAPS and it shows the same part # for the turbo and non-turbo part so I'm wondering why some people say they are different? I'm getting part # MD001402 for both. Are they indeed different or am I looking up the wrong part? Any help is greatly appreciated!

 

[SFRacingGST]

Im glad you dug this up because i am having high oil pressure also. I was wondering if anyone has used the N/T Internals since DJ and the results.I will port if thats the only solution but i want to see if theres another way around this one

 

[d j]

I used the NT internals & didn't have any problems (i've since sold the car).

What I wonder though is if any of the other oil-pump-related pieces are different in terms of pressure. the volume would be the same or abouts... this is the only piece i could spot with limited access & info. for me, it worked. ;]

 

[92GSXman]

I used the NT internals & didn't have any problems (i've since sold the car).

What I wonder though is if any of the other oil-pump-related pieces are different in terms of pressure. the volume would be the same or abouts... this is the only piece i could spot with limited access & info. for me, it worked. ;]

Great info but the funny thing is I checked the part #'s on CAPS for a 91 GS and a 91 GSX and it showed the same part #'s for both. The oil filter housings were different and looked nothing alike of course but the small piston was the same.

I'm sure you held them side by side, what were the differences that you saw? Also what year model was your engine and do you remember what year model the NT parts came from?

 

[d j]

Yeah the only difference I could visually see is that the filter housings look identical, the internals i did find only one difference - the height of the piston itself. if memory recalls correctly, the difference was only a few mm (i did use a digital caliper to measure).

The spring rate was something i didn't check, sorry.

the parts were 1g '91+ (bought 'em used).

Great info but the funny thing is I checked the part #'s on CAPS for a 91 GS and a 91 GSX and it showed the same part #'s for both. The oil filter housings were different and looked nothing alike of course but the small piston was the same.

I'm sure you held them side by side, what were the differences that you saw? Also what year model was your engine and do you remember what year model the NT parts came from?

 

[Nicks2319]

So is anyone offering this service for $$$ yet? I'm about to receive my 90 style housing, and I need it ported but do not have the tools or know how.