Porting the oil relief hole with no balance shafts? - Page 3

danl · 01-27-2007, 06:17 PM

Quote:

Originally Posted by 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.

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 · 01-27-2007, 08:30 PM

Quote:

Originally Posted by 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.

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 · 01-31-2007, 10:23 PM

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 · 02-01-2007, 07:30 AM

Quote:

Originally Posted by 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?

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:

Quote:

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 · 05-08-2007, 11:17 PM

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

mavisky · 05-09-2007, 05:43 AM

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

Elvenhome21 · 05-09-2007, 06:16 AM

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

d j · 05-09-2007, 07:32 AM

Quote:

Originally Posted by JWoodley

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 · 05-23-2007, 10:10 AM

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 · 07-14-2007, 08:03 PM

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 · 07-14-2007, 09:05 PM

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 · 07-14-2007, 10:09 PM

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 · 07-15-2007, 01:17 PM

Quote:

Originally Posted by 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. ;]

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 · 07-15-2007, 03:14 PM

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).

Quote:

Originally Posted by 92GSXman

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 · 07-30-2007, 06:36 AM

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.

DSM90AWD · 07-30-2007, 07:06 AM

Quote:

Originally Posted by 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.

I don't think anyone would want to do this work for someone they didn't know at any price knowing the risks/liability.

If you currently have a high oil pressure problem (e.g. goes over 100psi) here's a quick FAQ on how I did mine:**

1.) Remove that large shiney (if new) brass bolt which holds the relief spring and piston into place.
2.) With a small flat file (cost you a buck or so at any hardware store) carefully profile the top/sides of the OEM teardrop shape (e.g. "U" part furthest from the bolt you removed) so that it looks like "|_|"). There is no exact formula for how much to cut away as oil pressures vary, just be careful not to cut too much from the top that you expose the top of the piston when it's at rest.
3.) Finish off with some 220+grit sandpaper to smooth/debut the edges of the outlet port.
4.) Thoroughly clean the work area with solvant to get rid of any/all AL particles.
5.) Put some fresh oil on the piston and reinstall.

It should take you no more than 10mins start to finish.

**Liability Notice: Note this is what I did and it worked for me. Do at your own risk

babyviper · 08-09-2007, 12:30 AM

If I am right, I assume that this relief valve works like a waastegate. So in theory the larger the hole on the piston the more efficiently it releases the pressure. If your not sure what I'm talking about I provided a picture of the hole I am assuming would work best to port.

GSX_Dan · 08-22-2007, 11:54 PM

I've ported my relief hole pretty good and I've pushed out 2 oil pump seals so far within 2000km. I've also blown the seals on my turbo shortly after I built my g4cs. My next turbo was smoking badly from the getgo until I fed it from the head and went from a -4 to a -3 line. The pressure on the stock gauge doesn't show anything abnormal....I'm about to try the N/T piston and spring and see where that gets me and also installing a real gauge.

4wd-Eclipse · 08-23-2007, 04:56 AM

After porting that hole the oil pressure reduced from +6 bar (+87 psi) to 5 bar (73 psi).

DSM90AWD · 08-23-2007, 08:34 AM

Quote:

Originally Posted by babyviper

If I am right, I assume that this relief valve works like a waastegate. So in theory the larger the hole on the piston the more efficiently it releases the pressure. If your not sure what I'm talking about I provided a picture of the hole I am assuming would work best to port

The piston hole is not what needs to be ported, its the aluminum filter housing bypass hole itself. A better port job would be to port more of a straight edge (as shown by the red line)

Note, pushing oil past the turbo oil rings is not always due to high oil pressure. Remember that what goes into the turbo's oil jacket must come out, so if the return line is undersized or otherwise restrictive (excess crankcase pressure, kinks, crap in the line) even normal oil pressure could push oil past the oil rings