100 psi oil pressure. whats wrong?

[Jay Zarcadius]

Alright i just did a full rebuld on a NT 6 bolt block. It was built to be a turbo motor, has turbo pistons installed, kept balance shafts, everything was bought to make it a stock turbo rebuild except the block/crank/rods. only thing aftermarket 272/272 cams. Only thing missing should be oil squirters. I'm using a prosport gauge/sending unit. the sending unit is in the stock location, i checked the wiring to make sure everything is correct several times.

gauge at 1500 rpm (cold engine) is reading just a hair over 100 PSI (about 102-3 ish). I haven't gotten the engine warm because i'm afraid of damaging something if the gauge is accurate. i've put too much into this already and can't afford to risk it. someone give me some pointers?

EDIT: I just remembered the head was from a 7-bolt. stock head was damaged beyond repair and it was the only thing i could get. would that be causing any issues with this?

EDIT 2: Okay oil pressure seems to be doing alright from what the thread has told me so far. for anyone new, skip down to post #14 need help with idle/rough running issue. Just trying to keep anyone from reading more than they have to.

 

[greyspyder117]

my 97 spyder cold rev up a little bit 1500-2000 rpm hits 100psi oil pressure i never knew this was bad......

 

[Jay Zarcadius]

i'm afraid it's going to blo some gaskets out or something that's alot of pressure. and most of the gaskets on this thing were cardboard/paper material. it shouldn't be near that high... not with everything set up stock... look at your tires, bet they say either 44 or 50 psi max. if tires can't take that kind of pressure i dont see how those gaskets can for very long.

 

[BrandonDSM]

7 bolt heads have smaller head bolt holes don't they? That could be the problem if you're using a 6 bolt block. Not enough room for the oil to flow freely through the galleys, causing your high pressure.

 

[Jay Zarcadius]

yes the bolt holes were smaller, but the ports weren't any smaller.

 

[hubz91talontsi]

Both of our built blocks here have 110psi cold starts. Ive never had a problem i daily drive my car.

 

[Jay Zarcadius]

thanks. i'd like to have more input though. that just seems crazy high to me but if that's the way it is then that's the way it is.

what kind of pressure do you see at a warm idle Hubz? what kind of range does it get to through the RPMs?

EDIT: and what does "built" mean exactly?

Sorry for double post but any help would be awesome. I'm working on this in class and i get out at 9:30

I was hoping to drive it home for the first time tonight so i'd like to know if that pressure is "normal" (for DSM standards of normal anyway) and what it should be if i let it warm up.

thanks

 

[hubz91talontsi]

By built i mean a slowboyracing motor. I received in a trade. Idle i see around 30ish at 1krpm. Usually doesn't go over 50 cruising, but i run 10w40 full synthetic.
One motor runs 8.5 compression, and the other 9.0.

 

[BoostedBeaver]

Hey try looking up "oil port mod" Part one and two. These post are very helpful and explain how the 7 bolt head has smaller 11mm holes while 6 bolts 12mm I think. I know it is 1mm different. Your oil actually goes around one of your head bolts so if you used the bigger bolts in the smaller holes, This could be your problem. Also the bigger bolts will fit its just that the clearance in which the oil would normally have around the head bolt is reduced. Not to do the port mod because you still have bs but it will help you more understand what I am trying to explain. Hope this helps.

 

[JusMX141]

You need to port the relief valve hole in your filter housing; possibly even cut the spring in the pressure relief valve a bit to keep this under control. Excessive oil pressure isn't healthy for anything in the engine, including your turbo.

 

[OEM]

My stock 193k motor on cold startup hits about 100psi for about a min or two then begins to come down. Doesn't sound like it should be a problem unless it does not drop after a min or two.

 

[Hubbell91Tsi]

ive seen well over 100 when i pull out on my build shortblock with no blance shafts. probably close to 130 psi.

 

[talon_swift7834]

I also see over 100psi on cold starts. ###### close to 120-130. After it warms up it drops down to where it should be. I never drive my car before it completely warms up. I also have balance shafts removed. Almost all 4g cars are known for having this "issue". I have not had any issues with gaskets leaking. Over 17000 miles on engine.

 

[Jay Zarcadius]

So survey says let it warm up and see if it goes down. okay i'll try that tonight, and if it doesn't drop once it starts to warm up then i guess the relief valve is getting ported. thanks for the help so far i'll post tonight when i find out more.

okay. Good news and bad news.

Good first. Oil pressure seems to be going down as engine heats up like most of you above stated, went down to about 60 by the time the temp gauge got up to the edge of the "normal" zone (@ about 12-1500 RPM). this seems to be going in the right direction from what everyone is telling me.

The Bad. The car will not idle (pretty sure this is unrelated) if i give the car any sort of throtle at all it will keep running, even just barely putting pressure on the pedal with my foot. it is a bit rough running, and if i let all the way off the gas it will die out. Shoot me some probable things to check?