Stock oil pressure gage and fuel pressure issue

[fidstang]

I have noticed that my oil pressure gauge is getting lower on the readings then it was last year. It normally stays in the mid to high points in the normal lettering on the gauge. Now it is going toward the lower points (between the o and r of normal) of the lettering. while driving it stays in the middle, get on the throttle and it jumps to the upper level (about the L on the lettering). Is this ok or is their a problem starting to show. It doesn't smoke or knock and I feel no powerloss. While under the hood checking my timing and doing a tune up I also noticed the fuel pressure is @ 31- 32lbs. WTF! Like I said no knocks smoke or lean conditions, am I just losing my mind! LOL

 

[The Shape]

You can't trust the stock oil pressure gauge. It's best to install an aftermarket gauge. I prefer a mechanical full sweep gauge , but even an electric autometer is way way better than the stocker. I just put my mechanical gauge in a few weeks ago and you would be amazed at how far off the stocker is. Full hot idle I have around 20 psi and as soon as I touch teh throttle it jumps up in the 30's and levels off around 48 at 2K rpm's. While the autometer is showing the high 40's the stocker is still setting at about 1/4 way up.

 

[fidstang]

I also noticed that my dip stick shows half a quart too much oil but I only put in 4 quarts. Well 3 and 1 lucas oil additive. What does a small block usually run at, fuel and oil pressure?

 

[The Shape]

Alot of guys have had to remark there dipsticks because they read wrong. The 5.0 takes 5 quarts with a filter change, Best thing is to get the motor up to temp, cut it off and let the oil drain for awhile. Then put on a fresh filter and pour in 5 quarts of oil. Crank the car and let it idle a while, cut it off let it cool then pull the dipstick and mark where ever the oil reaches to as your new "full" mark. As far as the oil pressure anywhere around 20-25 psi at hot idle and 40-50 is about average for a 5.0 with close to or over 100k. Basic rule of thumb is 10 psi for every 1K rmps. So technically if you are idling at 650 rpms you should be safe with 6.5 psi although you would ideally like to see 20 and up.

 

[fidstang]

What about the fuel pressure at 31 to 32 psi? I still have the stock pressure regulator. I thought that they are set at 38 with the vacum line on?

 

[HISSIN50]

Nope, 30+ PSIG for fuel pressure is acceptable with the vac line on the FRP. If you remove the vac line on the FPR, that simulates WOT (in regard to the FPR operation) and it should go up to 38-39 PSI.

Good luck.

 

[fidstang]

Good, that makes me feel better now I can move on to what I needed to do in the first place. Trakloc rebuild. Thanks.